HX Stomp High Impedance Headphone Volume

[chanson91]

New Helix user, and I'm starting with the HX Stomp. Right now due to my living situation (baby and thin walls) I can only play using headphones. The headphones I have currently are AKG 240's. They only have a 55 ohm impedance.

 

On higher gain settings they sound pretty decent for sharp distorted chuggy tones, but I'm having a lot of trouble getting decent tones otherwise. Any fuzzy pedals, saturated break up tones (even slightly) etc sound awful. It's all mud with no definition or clarity, and farting out. And I am using cab sims, plan to buy some IRs soon.  Ive tried copying settings and EQing from various videos and even using the exact same settings, it sounds so wrong. After my researching on this forum, my best guess is that my headphones are too low impedance. I know the sound with headphones will never be exactly the same, but something definetely isn't right.

 

I've been considering getting some very high quality 250 ohm headphones, but I've heard a few people say that with the HX Stomp in particular, 250 ohm headphones can barely get loud enough with the volume cranked. Can anyone with an HX Stomp confirm or deny this?  Im curious if people have any input, suggestions, or experience using 250 ohm headphones with the HX Stomp in particular.  

 

I'm not even sure if I'm on the right track, but even with a bit of tweaking, most of the non high gain models sound like absolute mud.  Are my headphones just not great? Does their impedance not even matter?

[lou-kash]

17 hours ago, chanson91 said:

AKG 240's. They only have a 55 ohm impedance.

I have AKG K271MkII, also 55 Ω, and I use them as studio headphones all the time. This kind of AKG headphones are supposed to sound mostly linear which is a Good Thing™. Mine sound great with the Stomp. No idea how much different the AKG 240 are though.

 

Even though for practicing I actually prefer my old DJ headphones Sony MDR-V500 (40 Ω, apparently) which have slightly more bass and mid punch, and are a bit louder – just as one would expect from DJ headphones. :)

 

What you can do, for example, is first adjust your presets to your liking using regular speakers, then plug in the headphones and use the Global EQ to reshape that sound for your headphones. Then, whenever you're playing with regular speakers/amp, simply bypass the Global EQ again.

[lou-kash]

Actually I just noticed one thing that makes quite a difference on the amp sound: the balance between "Drive", "Chanel Volume" and "Master".

As noted in the manual, turning up the Master in particular emulates an overdriven power amp which will – of course – make things muddy and fuzzy. Especially if you're playing a humbucker guitar with high output. So if you want a clean sound to begin with – regardless which headphones you use – you may want to set the amp's Master no higher than 5.0 while making up the volume with Channel Volume or with the cab's end Level.

[datacommando]

13 hours ago, lou-kash said:

Actually I just noticed one thing that makes quite a difference on the amp sound: the balance between "Drive", "Chanel Volume" and "Master".

As noted in the manual, turning up the Master in particular emulates an overdriven power amp which will – of course – make things muddy and fuzzy. Especially if you're playing a humbucker guitar with high output. So if you want a clean sound to begin with – regardless which headphones you use – you may want to set the amp's Master no higher than 5.0 while making up the volume with Channel Volume or with the cab's end Level.

 

HI,

 

The "Master" and "Drive" act like they would with a real amp, therefore you adjust those (along with Bass, Mid, Treble etc.) to create the tone you are after, Clean, Crunch,  Dirty or whatever. The "Channel Volume" will then make that disired tone louder or quieter on the output of your choice, Monitors, Phones, FRFR cabinet without changing your overall "tone". You can use "Channel Volume" to balance out your output from your various presets so you don't get wildly variable volumes. Probably made that description weirder that it actually is?

 

Hope this helps/makes sense.

 

 

[lou-kash]

1 hour ago, datacommando said:

The "Master" and "Drive" act like they would with a real amp, therefore you adjust those (along with Bass, Mid, Treble etc.) to create the tone you are after, Clean, Crunch,  Dirty or whatever. The "Channel Volume" will then make that disired tone louder or quieter on the output of your choice

 

Exactly.

What's slightly confusing here, however, at least for a Helix Universe novice like me, is that the "Channel Volume" usually appears before "Master" in the parameter chain. It should be the other way around, following this signal path logic.

 

Anyway, we're getting slightly off topic here. :)

[donkelley]

Just FWIW, For years I used preamp distortion only on guitar, never power amp drive because I didn't have useful tube power amp stages. Then when I did go all tube for guitar, I was at home so never could get loud enough to not deafen myself before power stage would start to clip.

 

When I finally rehearsed with my band with my tube amp, I cranked the master and opened it up - and loved it, until I actually tried to control it with my gain staging etc, and to go clean.  Then I heard it miked up - and didn't love the tone any more with power amp clipping than without it, and in fact liked the preamp clipping more since I could filter the top end of it with the treble control in the tone stack.

 

So, for me... I just don't particularly love dealing with power amp clipping.  It can sound great, but it's so hard to manage in a recording situation like this that I understand why it might sound like that to you with headphones (assuming you are getting power amp distortion).  It's just kind of fuzzy and brittle compared to preamp or pedal overdrive tones.

 

So maybe that's part of it.  240 headphones are a speck middy, also..... and can slightly emphasize presence area, which can sound fizzy.  Great phones, but not neutral.

 

 

[EooN]

Regarding the impedance - I recently switched from ATH m40x to Beyerdynamic DT770 80ohm. 

When it comes to volume, the only thing I did is changed my physical volume dial setting from 1/3 to a bit above 1/2. Considering the fact that the presets themselves have a lot of volume available on tap, I'm pretty confident that you can drive 250ohm cans with Helix. As a matter of fact, many people swear by 250ohm DT770s for Helix.

After reading a few articles I went for the 80ohm version myself and I gotta tell you - they slay the ATHs I used before.

[donkelley]

oh yea, and I wanted to point out - high impedance phones are simply harder to drive... IE: quieter.  Tone doesn't improve, nothing darkens or brightens necessarily due to the impedance mismatch.  It's not like passive instruments and the effects of impedance, or simple stomp boxes.

 

50ish or less impedance headphones should normally be used unless you want to daisy chain them in a studio for multiple headphones on one headphone amp, all in parallel (which is what akg 240monitors were designed for... with 600 ohm impedance... but those are a specialty version, not what you are running).

[qwerty42]

9 hours ago, donkelley said:

high impedance phones are simply harder to drive... IE: quieter.  Tone doesn't improve, nothing darkens or brightens necessarily due to the impedance mismatch.  It's not like passive instruments and the effects of impedance, or simple stomp boxes.

Based on everything I've read, this isn't necessarily true. The output impedance of the device driving the phones does have an effect, and a device with a high output impedance might sometimes have a harder time driving low impedance headphones. (Edit: this is indeed different than how impedance mismatch affects guitar pickups. One is a source, one is a output. But if the the ratio of headphone impedance to output impedance is low enough, it can make the headphone amp struggle to drive the phones and may result in weaker bass or distortion, for example). Basic circuit analysis math with the two in parallel shows why this is the case. Somewhere in the past I already wrote up a post about this... I'll have to search and find it again.

 

In short, the output impedance of the Helix Floor is not that low by modern standards, and by the typical guidelines of headphone vs output impedance, the Floor should ideally be used with headphones of ~100 ohm or greater impedance. I can't speak for the Stomp, because to my knowledge L6 has never published its output impedance specs, but I can say a user just recently had this same question here, bought the 250 ohm version of the Beyerdynamic phones for his Stomp, and replied back here and said they worked great.

 

Lastly, measurements of the same kind of headphones that are made in multiple impedance versions do show slight differences. The lower impedance models tend to ring more with certain frequencies.

 

FWIW, I have a set of 250 ohm (edit: oops, actually 300 ohm) Sennheiser HD600 that I use with my Floor. They sound fantastic and get loud enough to definitely cause hearing damage. I've also tried plugging in cheap low impedance earbuds that came with my phone, which should be way more efficient based on impedance alone, right? Yet, for similar volume knob settings they are not noticeably louder. They just sound like trash.

[donkelley]

1 hour ago, qwerty42 said:

Based on everything I've read, this isn't necessarily true. The output impedance of the device driving the phones does have an effect, and a device with a high output impedance might sometimes have a harder time driving low impedance headphones. (Edit: this is indeed different than how impedance mismatch affects guitar pickups. One is a source, one is a output. But if the the ratio of headphone impedance to output impedance is low enough, it can make the headphone amp struggle to drive the phones and may result in weaker bass or distortion, for example). Basic circuit analysis math with the two in parallel shows why this is the case. Somewhere in the past I already wrote up a post about this... I'll have to search and find it again.

 

In short, the output impedance of the Helix Floor is not that low by modern standards, and by the typical guidelines of headphone vs output impedance, the Floor should ideally be used with headphones of ~100 ohm or greater impedance. I can't speak for the Stomp, because to my knowledge L6 has never published its output impedance specs, but I can say a user just recently had this same question here, bought the 250 ohm version of the Beyerdynamic phones for his Stomp, and replied back here and said they worked great.

 

Lastly, measurements of the same kind of headphones that are made in multiple impedance versions do show slight differences. The lower impedance models tend to ring more with certain frequencies.

 

FWIW, I have a set of 250 ohm Sennheiser HD600 that I use with my Floor. They sound fantastic. I've also tried plugging in cheap low impedance earbuds that came with my phone, which should be way more efficient based on impedance alone, right? Yet, for similar volume knob settings they are not noticeably louder. They just sound like trash.

 

Well, distortion is from clipping the amp - IE, it's not powerful enough to get loud, struggles with the impedance.  That isn't frequency response.

 

Bass?  Bass comes from power, which clips first when you run out of power.  Hifi folks might choose high impedance phones to tame harshness... but that isn't a crowd that actively uses science or electronics in the most efficient way to accomplish their goals.......

 

Anyhow - I personally wouldn't advise anyone to choose a higher impedance headphone to alter the eq of the tone.  You'll mostly just get a much quieter level, and it will showcase any deficiencies in the headphone amp of whatever is driving it.

 

There are other factors also, besides just impedance to take into consideration.   Different high impedance headphones may exhibit other different electrical characteristics that make them easier or more difficult to drive, other than just needing more power to handle the vastly higher impedance.  There's an amazing pair of headphones by, if I remember correctly, Beyerdynamic (could be remembering the wrong pair here), that is exceptionally hard to drive, needing more than just extra power to sound right.

anyhow - certainly ANY different pair of headphones will sound different from what you have, as long as you avoid akg 240 series.  I would still go for normal headphone impedance (roughly 56 ohms or less), so you're not giving teh headphone amp a difficult load, and so it's not excessively quiet.

 

Cheers

 

 

[qwerty42]

6 hours ago, donkelley said:

 

Well, distortion is from clipping the amp - IE, it's not powerful enough to get loud, struggles with the impedance.  That isn't frequency response.

 

Bass?  Bass comes from power, which clips first when you run out of power.  Hifi folks might choose high impedance phones to tame harshness... but that isn't a crowd that actively uses science or electronics in the most efficient way to accomplish their goals.......

 

Anyhow - I personally wouldn't advise anyone to choose a higher impedance headphone to alter the eq of the tone.  You'll mostly just get a much quieter level, and it will showcase any deficiencies in the headphone amp of whatever is driving it.

 

There are other factors also, besides just impedance to take into consideration.   Different high impedance headphones may exhibit other different electrical characteristics that make them easier or more difficult to drive, other than just needing more power to handle the vastly higher impedance.  There's an amazing pair of headphones by, if I remember correctly, Beyerdynamic (could be remembering the wrong pair here), that is exceptionally hard to drive, needing more than just extra power to sound right.

anyhow - certainly ANY different pair of headphones will sound different from what you have, as long as you avoid akg 240 series.  I would still go for normal headphone impedance (roughly 56 ohms or less), so you're not giving teh headphone amp a difficult load, and so it's not excessively quiet.

 

Cheers

 

 

I understand what you're saying, and I mean this very respectfully, but I'm not sure that advising 56ohm or less headphones for Helix is good advice. The output impedance of Helix Floor is 12 ohms. That is quite a bit higher than most modern audio devices, like smartphones, mp3 players, etc. Low impedance headphones exist to work with devices that have very low output impedances.

If you attach a pair of low impedance headphones to a headphone amp with high output impedance, that can be *harder* for the amp to drive than a pair of high impedance headphones. That's because the voltage drop across the load of the headphones is greater, due to it being closer in value to the impedance of the output. In its most basic form, it's just a voltage divider circuit, so a low impedance pair of phones on a high impedance output is not a recommended configuration. It might be ok; it might not -- it depends on the voltage and current capabilities of the amp.

This is where the commonly advised 8:1 rule comes from -- the rule of thumb is that headphone impedance should be at least 8 times greater than the output impedance of the headphone amp. In the case of Helix Floor, that's 12 * 8 = 96 ohms. The reason for the value of 8 has to do with the perceivable effect it has on response, and theoretically that's at the threshold where any negative effects of the impedance mismatch shouldn't be audible.

FWIW, the reason I mention all this is I've seen quite a few complaints about sound from Helix in headphones here, and on other places on the web, and almost universally they are using lower impedance headphones. On the contrary, I don't think I've seen any complaints from people using high impedance headphones, and have also seen a fair bit of praise from people who say their Helix sounds great with their 250 or 300 ohm headphones.

good article on it here: https://www.headphonesty.com/2019/04/headphone-impedance-demystified/
 

[donkelley]

16 hours ago, qwerty42 said:

I understand what you're saying, and I mean this very respectfully, but I'm not sure that advising 56ohm or less headphones for Helix is good advice. The output impedance of Helix Floor is 12 ohms. That is quite a bit higher than most modern audio devices, like smartphones, mp3 players, etc. Low impedance headphones exist to work with devices that have very low output impedances.

If you attach a pair of low impedance headphones to a headphone amp with high output impedance, that can be *harder* for the amp to drive than a pair of high impedance headphones. That's because the voltage drop across the load of the headphones is greater, due to it being closer in value to the impedance of the output. In its most basic form, it's just a voltage divider circuit, so a low impedance pair of phones on a high impedance output is not a recommended configuration. It might be ok; it might not -- it depends on the voltage and current capabilities of the amp.

This is where the commonly advised 8:1 rule comes from -- the rule of thumb is that headphone impedance should be at least 8 times greater than the output impedance of the headphone amp. In the case of Helix Floor, that's 12 * 8 = 96 ohms. The reason for the value of 8 has to do with the perceivable effect it has on response, and theoretically that's at the threshold where any negative effects of the impedance mismatch shouldn't be audible.

FWIW, the reason I mention all this is I've seen quite a few complaints about sound from Helix in headphones here, and on other places on the web, and almost universally they are using lower impedance headphones. On the contrary, I don't think I've seen any complaints from people using high impedance headphones, and have also seen a fair bit of praise from people who say their Helix sounds great with their 250 or 300 ohm headphones.

good article on it here: https://www.headphonesty.com/2019/04/headphone-impedance-demystified/
 

 

I suggested less than 60 ohms because, for headphones,, anything less than roughly 50 or 60 ohms is "normal"... IE, "Low impedance". 

 

Driving 60ohm or less headphones for not only the helix, but any device, is extremely solid advice.  You will be lucky to be able to drive higher impedance headphones with anything other than a vintage solid state stereo speaker amp that uses the same output amp to drive headphones (with resistors in place to lower output), or a dedicated, specialized, rather expensive headphone amp that is built to deliver much higher output levels than standard for, well, standard headphones (which are, as noted, anything lower than roughly 60 ohms).

 

There are some unique headphones in the world.  Most manufacturers, such as AKG, do NOT alter the tone of the headphones between the various impedances.  They sound the same, within the same model.. or if there are differences, they are very very subtle.

 

Beyer has one that is 600 ohms, and it sounds different from the lower impedance versions because it uses far far more coil windings but with finer wire.  But most high impedance versions don't sound any different simply because they are high impedance.  The impedance is an electrical factor that is intentionally met in the design, as is the tonal characteristic.  With tons of windings at a very small diameter of wire, they could have reached a lower impedance.  They chose that design because they can... because some home stereo dedicated amps (of higher quality) can drive 600 ohm phones just fine.  It's not super practical though, and nearly all gear does not drive 600 ohm phones to a particularly loud level without the amp clipping very audibly.

 

The helix output impedance is 11 ohms?  That's pretty normal.   The output impedance of the headphone amp is typically several times LOWER than the standard headphone impedance it is designed to drive, but it is not indicative of the headphone impedance it must drive to work well.    An 11 ohm output impedance does NOT mean you should be trying to find 11 ohm headphones (which I suspect don't exist).  It means it works like any normal headphone amp and will run standard low impedance headphones, and it doesn't hurt to try high impedance phones but I'd not expect great performance.  My helix LT can't drive my AKG 600 ohm phones very well, just for example.  They sound fine, but very quiet, and mid heavy as those phones always sound.

 

The stereos I grew up with in the 70s and 80s just used the resistors in series with speaker output method for headphones, typically, and sounded fine with anything, low or high impedance.  Then I got better stereos with dedicated headphone amps and suddenly the high impedance phones didn't sound as good.  Ironic, isn't it? 

 

 

Note: the site you mentioned, and most others, ONLY seem to talk about beyer headphones having different tone for the high impedance model.  They use them as some kind of example, because the model of phones exists in different impedances, and sounds different.  They sound different because the 600 ohm version is their high end one.  AKG 240s come in different impedances, yet they aren't referenced, even though they were a standard long long before beyer (and I am NOT saying they are as good - I typically would take beyerdynamic phones over most others, if price was no object).  This difference in tone between impedances is NOT true of AKG or some other major headphone manufacturers.  There ARE differences in tone between other changes in the 240 series (there are dramatic changes in how they are made between the "sextet", monitor, studio, DF and so on).  But 240s and 240m sound virtually the same, despite the s being 55 ohms, and the m being 600 ohms.  The beyer 770 example is a unique thing without any standard, and only is that way because of how beyer designed them.  There is not standard correlation between impedance and tone.

 

 

Folks complain about headphones on the helix because you can hear distortion fizz with headphones.  This is quite normal.  If you play through a hifi speaker set or certain studio monitors, you will hear fizz if you are close to the tweeter also.  Same reason.  Revealing/accurate high frequency driver close to your ears, or aimed directly at your ears at the very least (on axis, not angled away, since high frequencies are super directional).

 

It takes equing to get helix to sound great with phones or with revealing speakers.

 

Anyhow - I hope my information is helpful in some way.  At the very least it's another opinion from another experienced person who has dealt with recording engineering and speaker design/building a lot over several decades... and unlike some of the websites being referenced, I am actually explaining facts about headphones other than one specific, and unique, example (beyer 770, for example).

 

Cheers!  Hope you solve your headphone problem somehow, whether it's using trial and error, research based on web facts, or folks randomly on the forum like me!  LoL  :-)

 

Best of luck!

 

 

[Lynxpaw]

On 8/10/2020 at 11:04 PM, lou-kash said:

Actually I just noticed one thing that makes quite a difference on the amp sound: the balance between "Drive", "Chanel Volume" and "Master".

As noted in the manual, turning up the Master in particular emulates an overdriven power amp which will – of course – make things muddy and fuzzy. Especially if you're playing a humbucker guitar with high output. So if you want a clean sound to begin with – regardless which headphones you use – you may want to set the amp's Master no higher than 5.0 while making up the volume with Channel Volume or with the cab's end Level.

I’d say set the master between 0 and 2 and use a gain block between amp and cab/ir to compensate.  

[lou-kash]

16 minutes ago, Lynxpaw said:

use a gain block between amp and cab/ir to compensate

 

Why so complicated? Especially on a HX Stomp with its 6 blocks limit.

Almost every block has a Volume/Level slider, including the final output. You can make up the Amp volume loss at any stage after the Amp Master, whichever effect/cab/IR block you're using, totally for "free", without giving up a valuable block slot. Just make sure not to overdrive the device output with digital distortion.

 

21 minutes ago, Lynxpaw said:

I’d say set the master between 0 and 2

 

As previously noted, it's all about balance of several amp stages before the Master. If the Gain/Drive is relatively low and the Tone controls aren't fully cranked up either, you'll be still on the "clean" side with the Master set around 4 or 5.

[qwerty42]

16 hours ago, donkelley said:

 

I suggested less than 60 ohms because, for headphones,, anything less than roughly 50 or 60 ohms is "normal"... IE, "Low impedance". 

 

Driving 60ohm or less headphones for not only the helix, but any device, is extremely solid advice.  You will be lucky to be able to drive higher impedance headphones with anything other than a vintage solid state stereo speaker amp that uses the same output amp to drive headphones (with resistors in place to lower output), or a dedicated, specialized, rather expensive headphone amp that is built to deliver much higher output levels than standard for, well, standard headphones (which are, as noted, anything lower than roughly 60 ohms).

Again, I have to respectfully say 'ehhhh.' The low impedance headphone options that exist now came about because of portable battery-operated devices (phones, iPods, etc.), which can't drive the voltages necessary for higher-impedance headphones. But the output impedance of those devices is usually WELL below the 12ohm output impedance of Helix Floor and LT. Assuming the headphone amp in the Stomp is the same, then it's true for it too, but we don't know since L6 never published its output impedance.

Does it matter? Yes, it can, absolutely. Here's a page with a much better writeup on this, which even shows an example of a 10-ohm output impedance causing a significant/audible 6dB variation in frequency response for a set of 13-ohm headphones, causing bass roll-off and midrange emphasis:  http://nwavguy.blogspot.com/2011/02/headphone-amp-impedance.html
 

I never said that headphone impedance should match the output impedance of the device. I said the headphone impedance should, as a good rule of thumb, be at least 8 times greater than the output impedance. Again, for Helix Floor and Helix LT, that's 12 * 8 = 96 ohms.

Low impedance headphones are 'extremely solid device' for most modern portable battery-operated devices, which have very low (<<12 ohm) output impedances. Helix, for whatever reason they chose, does not fall into that category. Headphone impedance that is too low for the source driving it can be just as bad as it being too high. There is a sweet spot and it has a rule of thumb for a good reason. Sorry to beat this dead horse, but I want this forum to have accurate advice, and for this specific case I think your advice needs qualifiers added to it.

[datacommando]

18 minutes ago, qwerty42 said:

Helix, for whatever reason they chose, does not fall into that category.

Well, way back in 2017, in a thread entitled “ The Mother of all Headphone Complaint Answers”, there is a comment from Digital Igloo where he says: -

 

“Helix is professional gear “designed for professionals” and we weren't about to dumb down our headphone amp because everyone happens to have white earbuds in some drawer in their house. Feel free to use consumer cans, but don't expect it to sound great.”

 

Although, I thought that you would be already aware of this, as you went over all this stuff in the thread about headphone amps back in March this year. You actually posted a link to the comments from Eric (DI) which he made over on The Gear Page.

Must be the virus sending us all mad!

And the vet says the horse is dead!

[donkelley]

4 hours ago, qwerty42 said:

Again, I have to respectfully say 'ehhhh.' The low impedance headphone options that exist now came about because of portable battery-operated devices (phones, iPods, etc.), which can't drive the voltages necessary for higher-impedance headphones. But the output impedance of those devices is usually WELL below the 12ohm output impedance of Helix Floor and LT. Assuming the headphone amp in the Stomp is the same, then it's true for it too, but we don't know since L6 never published its output impedance.

Does it matter? Yes, it can, absolutely. Here's a page with a much better writeup on this, which even shows an example of a 10-ohm output impedance causing a significant/audible 6dB variation in frequency response for a set of 13-ohm headphones, causing bass roll-off and midrange emphasis:  http://nwavguy.blogspot.com/2011/02/headphone-amp-impedance.html
 

I never said that headphone impedance should match the output impedance of the device. I said the headphone impedance should, as a good rule of thumb, be at least 8 times greater than the output impedance. Again, for Helix Floor and Helix LT, that's 12 * 8 = 96 ohms.

Low impedance headphones are 'extremely solid device' for most modern portable battery-operated devices, which have very low (<<12 ohm) output impedances. Helix, for whatever reason they chose, does not fall into that category. Headphone impedance that is too low for the source driving it can be just as bad as it being too high. There is a sweet spot and it has a rule of thumb for a good reason. Sorry to beat this dead horse, but I want this forum to have accurate advice, and for this specific case I think your advice needs qualifiers added to it.

Fair enough.  I'm well aware that an 11 ohm output impedance can cause poor damping.  Shows that the headphone output wasn't a super high priority for line6... which is completely logical.  It's not supposed to be a high end headphone amp, and it's not designed specifically to target little portable headphones either.

 

But if you look around, you'll find most headphones are "low impedance"... whether studio, home, or portable, outside of the beyerdynamic world.  Pro headphones.  They all work just fine with the helix, I'm certain, and as with any low impedance load on an amplifier, can cause the amplifier to reach it's limits sooner, but also get louder in the process.

 

It's a little unfortunate that they let the output impedance be a bit on the high side, but it's not like they're trying to win audiophile headphone amp awards.  It's guitar we're listening to here, not an orchestra or full band (most often, at least).

 

Just to give a quick idea of the some of the great headphones you can buy, without searching for low impedance headphones (just searching for good headphones from big name manufacturers that would be worth testing to see if they sound good from the helix), I came across a bunch here, and these are all, completely by fluke, low impedance. I am aware that sennheiser and a couple other builders make high impedance models also, but those didn't come up in my search for professional headphones online.

 

Sennheiser HD 599 - 50 Ohms ($200 high end headphones).

 

Beyerdynamic DT 990 Pro - 80 Ohms (insignificantly higher than the low impedance range I quoted) - these are $200 pro studio headphones.

 

Sony MDR-7506, and 7509 - roughly 60 ohms, 7509 is higher end and has a different 5cm driver (7506 has a 4cm driver)... studio staples

 

Sennheiser HD280 pro - 64 ohms (another studio staple)

 

Sennheiser HD569 - high end full size over ear phones for portable use, with inline mic - 23 ohms (naturally).

 

Shure SRH440 pro - 44 Ohms.  Their highest impedance headphones are 65 Ohms, for "studio mastering".

 

KRK 8400 - 36 Ohms.

 

Philips X2HR - 30 Ohms.

 

 

LoL ok I want to stop now.  Some interesting models to try out.  I suspect they all soudn radically different from each other.

 

Hope this is helpful info!

 

And if you do find a pair of high impedance phones that sound really good with the helix, I'd love to find out which models specifically so I can try them out too sometime! 

 

But, honestly, you probably shouldn't just dismiss everything I told you - it's all pretty interesting history about headphone impedance and how they are driven.  Honestly - high impedance phones are such an ancient design, they're from way back when tube amps were in everyone's living room stereo cabinets.  These days, they are something of an anomaly, and there is a market of dedicated headphone amplifiers, stand alone AC powered semi-esoteric things, built specifically to drive high impedance phones.  When you have the right amp, they can sound glorious!  Without a truly great, and very powerful, headphone amp... they sound kind of meh, from my experience.

 

Very interesting thread!

 

QUESTION, though:

 

To quote you above:

"Low impedance headphones are 'extremely solid device' for most modern portable battery-operated devices, which have very low (<<12 ohm) output impedances. Helix, for whatever reason they chose, does not fall into that category. "

 

But earlier, this was posted:

" The output impedance of Helix Floor is 12 ohms. "

 

So I'm not sure which it is.  12 ohms is extremely close to << 12 ohms.  Yes, I agree, there are headphone amps in portable devices that are lower than 12 ohms, and lower is more ideal (to a certain degree) for working with low impedance phones.  But 12 ohms output impedance?  That isn't a problem for standard (IE: not high impedance) headphones, most of which present between about 30 and 60 ohms impedance (based on my list above).

 

I just googled - iphone 6, for example, had output impedance of just under 6 ohms to nearly 7 ohms.  That's pretty typical, it seems, for little battery powered devices.  Just backing up your points about these devices :-)

 

I'm trying to find headphone output impedance of popular home stereo amplifiers.... it's a spec that isn't published very often! Would be interesting to know, though :-)

 

 

 

[datacommando]

7 hours ago, donkelley said:

Shows that the headphone output wasn't a super high priority for line6

Once more, your psychic powers astound me! How do you know this?

 

Do you actually read any of the replies to this thread. I have already posted a comment from Digital Igloo, which I think negates your telepathic ability. So, to hammer it home, this is the quote repeated:

 

“Helix is professional gear “designed for professionals” and we weren't about to dumb down our headphone amp because everyone happens to have white earbuds in some drawer in their house. Feel free to use consumer cans, but don't expect it to sound great.”

 

Plus, this is the link to a response from Digital Igloo on TGP from way, way back in 2016, that was previously posted by “qwerty42”.

https://www.thegearpage.net/board/index.php?threads/line6-helix.1586637/page-1185#post-22007938

 

For anyone who cannot be bothered to check - this is the gist of the reply.

“Helix's headphone amp is LOUD; it's designed to drive high-impedance studio headphones to stage volumes. Low impedance headphones distort way faster, fatigue your ears, and at a high enough volume, can damage your hearing. With Helix you could conceivably split the headphone output to two pairs of 200-300 Ω cans/IEMs and drive both over the sound of a drummer (and adjust respective levels via MIDI CC control of path output blocks). My band does this now.

Personally, I use Sennheiser HD600s (300 Ω), and before those, the HD580s (same). Also have a bunch of Sony 7506s around, but they're 63 Ω and harsh-sounding already, even with an iPod. I also keep a pair of Sennheiser HD280 Pros (64 Ω) at work and they're pretty boxy sounding, but if I can get a mix to sound good on them, it'll sound good anywhere. I treat them like wearable Yamaha NS10s, if those NS10s were powered by an Alesis RA100 instead of a Bryston. Wouldn't want to construct tones with them.”

 

A follow on response states:

 

”A pair's Sensitivity and Max Input Power specs have a big impact as well. Basically, some headphones are the equivalent of cheap plastic 2" desktop speakers and others are the equivalent of high end studio monitors.”

 

As these statements were made by Digital Igloo (Eric Klein - Chief Product Design Architect at Yamaha Guitar Group, Inc. / Line 6 / Ampeg), if you have any issues with them, then you really should take it up with him.

 

The dead horse has now been canned and being sold as dog food!

 

Hope this helps/makes sense.

 

 

[donkelley]

5 hours ago, datacommando said:

Once more, your psychic powers astound me! How do you know this?

 

Do you actually read any of the replies to this thread. I have already posted a comment from Digital Igloo, which I think negates your telepathic ability. So, to hammer it home, this is the quote repeated:

 

“Helix is professional gear “designed for professionals” and we weren't about to dumb down our headphone amp because everyone happens to have white earbuds in some drawer in their house. Feel free to use consumer cans, but don't expect it to sound great.”

 

Plus, this is the link to a response from Digital Igloo on TGP from way, way back in 2016, that was previously posted by “qwerty42”.

https://www.thegearpage.net/board/index.php?threads/line6-helix.1586637/page-1185#post-22007938

 

For anyone who cannot be bothered to check - this is the gist of the reply.

“Helix's headphone amp is LOUD; it's designed to drive high-impedance studio headphones to stage volumes. Low impedance headphones distort way faster, fatigue your ears, and at a high enough volume, can damage your hearing. With Helix you could conceivably split the headphone output to two pairs of 200-300 Ω cans/IEMs and drive both over the sound of a drummer (and adjust respective levels via MIDI CC control of path output blocks). My band does this now.

Personally, I use Sennheiser HD600s (300 Ω), and before those, the HD580s (same). Also have a bunch of Sony 7506s around, but they're 63 Ω and harsh-sounding already, even with an iPod. I also keep a pair of Sennheiser HD280 Pros (64 Ω) at work and they're pretty boxy sounding, but if I can get a mix to sound good on them, it'll sound good anywhere. I treat them like wearable Yamaha NS10s, if those NS10s were powered by an Alesis RA100 instead of a Bryston. Wouldn't want to construct tones with them.”

 

A follow on response states:

 

”A pair's Sensitivity and Max Input Power specs have a big impact as well. Basically, some headphones are the equivalent of cheap plastic 2" desktop speakers and others are the equivalent of high end studio monitors.”

 

As these statements were made by Digital Igloo (Eric Klein - Chief Product Design Architect at Yamaha Guitar Group, Inc. / Line 6 / Ampeg), if you have any issues with them, then you really should take it up with him.

 

The dead horse has now been canned and being sold as dog food!

 

Hope this helps/makes sense.

 

 

Good info!  Thanks!

With a damping factor so poor for most of the headphones you can buy (IE: anything less than 120 ohms), it didn't seem likely to me that was a high priority, but I made an assumption and was wrong.  My apologies for the misinformation assumption, and to line6.

 

At least it has a lot of power to drive lots of types of headphones.  Even as some of them won't sound as good as they do on many other modern headphone outputs (due to insufficient damping to have predictable results with most headphones), others will sound better on the helix than they do elsewhere (due to sufficient power compared to weaker headphone amps).

 

Sorry for my assumption, again!  :-)

 

Oh, by the way, this claim is vague and could be misinterpreted in electronics:  " Low impedance headphones distort way faster, fatigue your ears, and at a high enough volume, can damage your hearing."

 

The headphone amp simply reaches it's maximum output power more easily with lower headphone impedance.  The headphones don't distort way faster unless they are overdriven, which isn't related to impedance but to output power and controlling the volume knob properly.  That output power is no less than it is with high impedance headphones, and clipping is not going to happen at lower volume or lower output power.  It's just that it takes less preamp gain driving the headphone amp to reach the limit with a smaller load in the circuit, and therefore the volume (preamp gain) knob should be kept lower.  The headphones themselves will not be any quieter if they are low impedance or high impedance, but you should never drive an amp into clipping for this purpose, so just expect it to require less volume to reach the highest output that the circuit can work at with lower impedance phones than high impedance phones. 

 

If any low impedance headphones are less loud and clear at the headphone amp's highest clean output before clipping (whatever the arbitrary volume knob setting is to accomplish that goal), then that is purely a side effect of the sensitivity of the headphones, not a side effect of the impedance.  Same could happen with high impedance headphones - sensitivity has no relation to impedance.  Sensitivity is measured in relation to the power the headphones are driven with so there is consistency.

 

In this thread I presented my own misinformation in assuming things about the priority of the headphone amp in the helix - I take that back, as it was incorrect! :-)

However, the misinformation about how headphones and amplifiers work is something factual in engineering, and I hope my repeated attempts to clarify facts about how it all works is helpful.

 

Oh, and OP - interesting and cool that the helix has power to drive high impedance phones!  Like I said a couple of times - I'm interested in your findings about which phones turn out to soudn best for you, as I'd like to try them too.  :-)

[qwerty42]

3 hours ago, donkelley said:

If any low impedance headphones are less loud and clear at the headphone amp's highest clean output before clipping (whatever the arbitrary volume knob setting is to accomplish that goal), then that is purely a side effect of the sensitivity of the headphones, not a side effect of the impedance. 

I know you have good intentions, but you are filling this thread with information that sounds authoritative and absolute but simply isn't. People who find this thread in a future search are going to be left scratching their heads with no better understanding than they started with, because of the contradiction and length of all the replies.

Your statement above is not always true. A headphone amp might be capable of delivering high current but low voltage. It might also be capable of high voltage but low current. The former is typical of portable devices, the latter is typical of older high-impedance outputs. The end result is that yes, sometimes low-impedance headphones can be poorly driven by amps with high output impedance, and vice versa, and yes, it is absolutely a side effect of impedance combined with the amp. Sensitivity matters too, but saying it's the only contributing factor to what you described is false.

If anyone's looking for headphone suggestions for Helix, anything in the range of 90 to 300 Ohms and 'pro quality' should work best. That's the ideal range. Anything between 50-90 Ohms, and pro-quality should also be acceptable. Anything with very low impedances (there's no hard number for this, but let's call it <30 Ohms) could indeed have audible consequences when coupled with Helix's 12-Ohm output. Personally, myself and many others on a different forum use the Sennheiser HD580/HD600/HD650 headphones (all 3 are very similar), which are 300 Ohm impedance, and I can say from hundreds of hours of experience that they sound great with Helix and get loud enough to harm your hearing.

I won't reply any more here because it's just adding to the noise, but for anyone who finds this thread in the future and really wants to learn this stuff clearly from an accurate reference, here are two great links. Your time would be better spent reading them than reading this thread:

• Headphone Impedance Explained
• Headphone and Amp Impedance

[donkelley]

49 minutes ago, qwerty42 said:

I know you have good intentions, but you are filling this thread with information that sounds authoritative and absolute but simply isn't. People who find this thread in a future search are going to be left scratching their heads with no better understanding than they started with, because of the contradiction and length of all the replies.

Your statement above is not always true. A headphone amp might be capable of delivering high current but low voltage. It might also be capable of high voltage but low current. The former is typical of portable devices, the latter is typical of older high-impedance outputs. The end result is that yes, sometimes low-impedance headphones can be poorly driven by amps with high output impedance, and vice versa, and yes, it is absolutely a side effect of impedance combined with the amp. Sensitivity matters too, but saying it's the only contributing factor to what you described is false.

If anyone's looking for headphone suggestions for Helix, anything in the range of 90 to 300 Ohms and 'pro quality' should work best. That's the ideal range. Anything between 50-90 Ohms, and pro-quality should also be acceptable. Anything with very low impedances (there's no hard number for this, but let's call it <30 Ohms) could indeed have audible consequences when coupled with Helix's 12-Ohm output. Personally, myself and many others on a different forum use the Sennheiser HD580/HD600/HD650 headphones (all 3 are very similar), which are 300 Ohm impedance, and I can say from hundreds of hours of experience that they sound great with Helix and get loud enough to harm your hearing.

I won't reply any more here because it's just adding to the noise, but for anyone who finds this thread in the future and really wants to learn this stuff clearly from an accurate reference, here are two great links. Your time would be better spent reading them than reading this thread:

• Headphone Impedance Explained
• Headphone and Amp Impedance

Wow. Ok.

 

I'll go back to engineering.  Cheers

 

Interesting forum you folks have here.

 

C'ya

[Lynxpaw]

On 8/21/2020 at 11:39 AM, lou-kash said:

 

Why so complicated? Especially on a HX Stomp with its 6 blocks limit.

Almost every block has a Volume/Level slider, including the final output. You can make up the Amp volume loss at any stage after the Amp Master, whichever effect/cab/IR block you're using, totally for "free", without giving up a valuable block slot. Just make sure not to overdrive the device output with digital distortion.

 

 

As previously noted, it's all about balance of several amp stages before the Master. If the Gain/Drive is relatively low and the Tone controls aren't fully cranked up either, you'll be still on the "clean" side with the Master set around 4 or 5.

You wouldn’t set the master that high in real life. The amps sound more realistic between 0 and 2 on NMV amps. 

[lou-kash]

2 minutes ago, Lynxpaw said:

You wouldn’t set the master that high in real life.

 

The nice thing about amp modeling is that it's not "real life".

Anything is possible. Even the, er, illegal settings. ;)

 

But yeah: In real life I built myself a passive attenuator for my Fender Blues Deluxe 1993 that I'm plugging in between the Preamp Out and Power Amp In because the clean channel's got no master volume and gets just frickin' loud anywhere above Volume 1.2  …

[qwerty42]

4 hours ago, donkelley said:

5 hours ago, qwerty42 said:

•  

Wow. Ok.

 

I'll go back to engineering.  Cheers

 

Interesting forum you folks have here.

 

C'ya

I apologize if my reply offended. I don't take any joy in hurting others, and I'm genuinely sorry if I did.

I see this forum as a place for people to get clear and concise help and answers to their questions, hopefully. When threads get as long as this and go back and forth with long statements that sound very convincing/authoritative but then get retracted in later replies, they become increasingly less useful to people who are just looking for answers--and then we end up with the same questions posted over and over again. That's what I meant in my reply when I linked those other two sites and said the time would be better spent reading them than this thread. I wasn't referring specifically to your posts, but the entire thing, including mine. Anyone who reads through those two links will have all the knowledge they need to answer their own headphone impedance questions and won't have to try to decipher the conflicting advice given in this thread.

[donkelley]

3 hours ago, qwerty42 said:

I apologize if my reply offended. I don't take any joy in hurting others, and I'm genuinely sorry if I did.

I see this forum as a place for people to get clear and concise help and answers to their questions, hopefully. When threads get as long as this and go back and forth with long statements that sound very convincing/authoritative but then get retracted in later replies, they become increasingly less useful to people who are just looking for answers--and then we end up with the same questions posted over and over again. That's what I meant in my reply when I linked those other two sites and said the time would be better spent reading them than this thread. I wasn't referring specifically to your posts, but the entire thing, including mine. Anyone who reads through those two links will have all the knowledge they need to answer their own headphone impedance questions and won't have to try to decipher the conflicting advice given in this thread.

Fair enough :-)

 

As I noted in my later post, I was mistaken in my assumptions about the helix headphone amp - or at least in the intent behind it's design.  It's unfortunate that it has a relatively high output impedance, because if it was a lower output impedance then it would be quite stable with nearly all professional headphones you can buy, most of which are lower than 60 ohms impedance (as my amazon search for "studio headphones" showed, just randomly... I wasn't looking for low impedance phones).  But I did completely mistake it's ability to drive high impedance headphones - it's odd that my akg high impedance phones don't behave well with it, but it seems high impedance phones do for others on the helix, and that the designers claim it was made for high impedance phones, which does jive with the output impedance, after I did the math.  So I based my assumption on an actual test wtih actual high impedance phones, but my test must have failed in some way.  Things happen - and I got called out on it by someone else (rather emotionally LoL).  Done deal.

 

It is, though, truly odd that the helix targets high impedance BETTER than most studio/professional/consumer phones.  It's not like most pro or studio phones are high impedance.  And of course, it's not like it won't work great with many low impedance phones - just that it won't support them as ideally, due to poor damping, as it could with lower output impedance.  Just a choice they made - obviously it was a trade off, and they went the way they went.  Fair enough!

 

I was, though, accurately summarizing the majority of differences between how amplifiers work with loads.  There are complexities related to how current and voltage work together to drive the voice coils in headphones to create the magnetic field.  Both voltage and current are part of every design.  It's not something that we can get into in this discussion, and doesn't help anyone.  Headphones don't supply enough data to calculate the way everything in the circuit will work, and the basic summary is you need more power to drive higher impedance phones.  Current/voltage are both part of that calculation, but it's not a simple calculation that we can predict since there is mechanical reaction in the headphones for physical damping that benefits differently from various power conditions.

 

So, imho, it was sort of a surprising reaction.  I, too, am just trying to contribute in my particular area of knowledge - which happens to be engineering, audio electronics, and pro audio (and music of course, as we're all musicians here!).

 

But it's ok, you clearly are very dedicated to figuring this out, and that's great - more power to you. 

 

I was just trying to point out that nearly all headphones are lower than roughly 60 ohms impedance, and nearly all headphones amps are made to drive those.  It turns out the helix actually isn't designed to - it apparently targets ONLY higher impedance phones (based on the output impedance and what I read in some quotes), and provides less than ideal damping for what I consider "normal" headphones (normal meaning nearly all headphones fit into this impedance range of less than 60ish ohms), which could result in some changes in frequency response compared to running those same headphones on another headphone amp.

 

It's pretty simple - and it's correct information.  It's just electronics facts, summarized in a useful way, without getting into guessing games about specifications that aren't listed.  Anything further requires measuring very specific details of the helix while connected to each specific pair of headphones while supplying a signal generator source sweeping the audible range, and so on... which, as I said, is way beyond this topic.

 

I do hope it works out for you and look forward to your findings!

 

Cheers - interesting thread!

[datacommando]

9 hours ago, qwerty42 said:

When threads get as long as this and go back and forth with long statements that sound very convincing/authoritative but then get retracted in later replies, they become increasingly less useful to people who are just looking for answers--and then we end up with the same questions posted over and over again.

If you think this stuff is convoluted, you really ought to check his insights into the Helix looper. I cannot figure out why someone puts so much effort into getting absolutely nowhere. Trying to communicate with someone going in circles is an exercise in futility, especially someone who always wants the last word.

 

When I fell into the trap of trying to unravel his waffle, I was described as:

“The most insulting arrogant person I've ever seen on a forum.”

I don’t mind that, because I think my people skills are just fine, it’s my tolerance of nonsense that needs more work!

 

[Lynxpaw]

6 hours ago, datacommando said:

If you think this stuff is convoluted, you really ought to check his insights into the Helix looper. I cannot figure out why someone puts so much effort into getting absolutely nowhere. Trying to communicate with someone going in circles is an exercise in futility, especially someone who always wants the last word.

 

When I fell into the trap of trying to unravel his waffle, I was described as:

“The most insulting arrogant person I've ever seen on a forum.”

I don’t mind that, because I think my people skills are just fine, it’s my tolerance of nonsense that needs more work!

 

Lower your expectations and you’ll never be disappointed.  :)

[donkelley]

15 hours ago, datacommando said:

If you think this stuff is convoluted, you really ought to check his insights into the Helix looper. I cannot figure out why someone puts so much effort into getting absolutely nowhere. Trying to communicate with someone going in circles is an exercise in futility, especially someone who always wants the last word.

 

When I fell into the trap of trying to unravel his waffle, I was described as:

“The most insulting arrogant person I've ever seen on a forum.”

I don’t mind that, because I think my people skills are just fine, it’s my tolerance of nonsense that needs more work!

 

I'm sorry folks - this guy decided after reading one post of mine on loopers (which was a supportive reply to the OP's complaint about the looper), that I was apparently incapable of knowing what I was talking about, and couldn't possibly understand how a company like Line6 creates their products or the complexities of adding features into firmware.  There was never any attempt to be polite, or possible acknowledge that I might actually have any experience of value in the industry.  Note:  I'm a mature senior software engineer and have been working in various types of software for most of my life (middle aged now), while most of my training is in both music and in audio engineering.

 

I'll leave it up to others here to decide if he's an insulting arrogant person to me, after what he just posted in this thread that was off topic completely, just to attack me.

 

So again, I apologize that he decided I'm an idiot, and not actually a really nice guy with a lot of knowledge on certain parts of the industry who's just trying to help contribute here to problem solving.

 

I'm telling ya - it's enough to drive me away from Line6 products after more than a decade of dedicated use.