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"4 Cable Method" and gain staging questions


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I've set up my Helix with a kind of traditional 4 cable method as a pedalboard for my Hughes & Kettner amp. My routing is as follows:


first path: Guitar Input > Effects > output Send 1 into Amp Input

lower path: Amp Send into Return 1 > Effects > output 1/4" into Amp Return


This works great, and if I turn off all the effects and leave stuff essentially at zero I have the same volume and general tone as when I run Guitar > Amp without the Helix or effects loop.


So I was curious when I went into the templates and found the 4 cable method template doesn't really do a traditional 4 cable method for effects chaining at all. It doesn't really have a place for you to put effects in the actual effects loop of the amp. Rather, it's there to allow you to bypass your amps preamp section all together, and instead use one of the Helix's modeled preamps. Pretty cool idea actually, as it allows you to use your cab and power amp section but basically have any preamp you want to test out. Makes for a versatile rig in principle. But the gain staging is totally off. If I set my actual H&K amp on the clean channel and put both gain and volume at 5, the preamp models in the Helix are often/usually very quiet, if not downright completely inaudible, unless I basically dime out the gain/channel/master volumes. Some of the amps will drive more, but most of them, like the Fender and Vox clones, are really too quiet to be usable, at least when compared to my actual preamp.


So is this a limitation, bug, feature, ? of the amp models? Would the suggested compensation, should I choose to build presets with this in mind, be to really boost the send/return values on the FX Loop block of the Helix?

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ITRW, if you run a preamp into a guitar cab, it's not going to be as loud as running it into a power amp first.

A preamp with four 12ax7 tubes will likely be much louder than one with two 12ax7's.

L6 models these things very accurately so yes, it's a feature.

One trick that some people use is to run a preamp into a full amp. It's like using an AIAB into the front of a real amp (like a MIAB or the Friedman BE stomp, NOT a pedalboard type power amp in a box! That'll cause the magic smoke to escape from your amp!).

If you put a Helix preamp into the front of your H&K (before the FX Loop) that's essentially what you're doing.


If you want to experiment with Helix preamps into the H&K poweramp, just turn off the FX Loop when you turn on the preamp (assign them to the same stomp or use snapshots). That'll simply replace the H&K preamp, but the FX that were between the H&K Pre and power sections will still be in the same place in the signal chain. If you really need for the Helix pre to be louder, add a gain block after the preamp.


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I'm confused as to the purpose of the 4 Cbl Method preset then. Because it seems explicitly to be able to use either your preamp, or the Helix preamp. It's even labeled as such and described as this design in this official tutorial video:


The only thing here that I haven't really done is adjust the 1/4" out to line level, as that isn't appropriate for my amp. The gain staging works just fine if I'm not using the Helix preamp models. The video above shows to adjust the FX loop levels to make it match the amp, this is fine for my amp when they're set at 0 for both pre and post. It's the preamp setting that's far too quiet, and there's no direct adjustment for this in the signal chain for that template. (I also don't quite understand why the template has the Split Y for the delay and reverb, but that's a different discussion).


In fact, even if I just run the preamp into the front of my amp like you're suggesting, the volume drops significantly unless I max out at least the Channel and Master volumes of the US Delux Nrm model in the template. That's the case for most of the models that aren't specifically very high gain things like the Brit Plexi.


FWIW, my amp is a Tubemeister 18, which just has a pair of preamp tubes (I have a mix with one 12AX7 and one 5157). It's not an insanely loud amp compared to anything with 4+ tubes in the preamp stage.

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Having never used the stock templates, I had to find my backup and reload them to duplicate what they're doing in the video.


I see what you're getting at. My amp is an Egnater Tweaker15-112, pretty much equivalent to your TM18 (two 12ax7 in the pre, one for the PI).

I get the same results as you. TBH, I've no idea why the HX Deluxe Pre should be so much quieter than the real world tube pre in my Eg. You'd have to ask L6 about that.

I'm going to guess that there's a disparity between the CHANNEL level on the HX pre and what actually gets sent from a real world preamp?

I always max the CHANNEL level in this scenario to approximate what would happen ITRW (see above) and still had to add 2 maxed out gain blocks to get close to a match - that's +12db on top of +12db.


I've attached a modded 4cm preset for you to see what I did.

I'm not sure why they set the BIG KNOB at 50%. I always MAX mine to prevent unfortunate on-stage accidents.

Also, I set the 1/4" level at LINE. I don't know why you think that's not appropriate for your amp. I don't think H&K designed it so that you could plug your guitar straight into the power amp, which is what INST Level is the equivalent of. It would be interesting to see what happens if you used an AIAB direct to the poweramp. Would it be a similar situation as with the HX pre?

If I had another amp with a two 12ax7 pre I'd try running that straight into my Eg's poweramp, but I don't.


The Y-split allows you to control the mix of direct and effected signal at the MIX block.

4Cable MethodTJB.hlx

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OK, so it turned out that I did have the 1/4" out to Line, but honestly that doesn't change much. Just changes where I have to set the BIG volume knob. I thought maybe setting the Send/Return to line instead of instrument would change things but it literally made no difference at all when I made those changes. I also tried using Send3 instead of the 1/4" out for the preset and that also didn't matter at all.


Your preset was actually way too loud. Only one volume block at +12dB was required for me to balance the regular amp. Still wild that you need to do that though. Guess that's just the way the models are done. I don't have an issue with them when I use a cab block, as those tend to add a LOT of gain/volume to the overall sound output (when going to an FRFR setup with XLR cables this is what I have done).

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  • 1 year later...
On 5/27/2023 at 12:23 PM, Tboneous said:

How does adjusting the send and refurn volume factor in when dialing in 4cm?


HX Send to your amp's input too hot (distorting the amp's pre)? Lower the SEND level.

HX Return distorting, but you like your amp's pre settings? Lower the RETURN level.

Level disparities when switching between HX amp and your amp's pre? Adjust as necessary per the above. (don't forget the Helix amp's Channel level)


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