Huge tone loss when placing fx loop block after amp block

[Luxferre]

Hi!

I'm having a big issue when using the fx loop of the HX Stomp XL, I'd like to put my delay and reverb pedals in the fx loop like in a real amp (between the pre amp and power amp), the closest to this is placing the fx loop block after the amp block and before the cab, but when I do this, I get a HUUUUGE tone loss, it's unusable, placing it after the cab gets extremely harsh and noisy but before the amp block I have no issue, but there's no point placing delay and reverb in front of a overdriven amp is you want a clear sound from them.

I've tried with lots of pedals and cables and this always happens, even jumping the fx loop with a patch cable I get tone loss, not terrible, but noticeable.

 

Is there a way to fix this? I've read a lot of topics about fx loop tone loss, but none pointed the placing of the block.

[theElevators]

attach your preset, or provide the screenshot of the signal chain please. 

[Luxferre]

On 6/26/2023 at 10:40 PM, theElevators said:

attach your preset, or provide the screenshot of the signal chain please. 

Base.hlx

[rd2rk]

If you're using "stomp" type FX (vs pro-grade rack FX) they expect an Instrument level input, so make sure you have the Send/Return set to Instrument.

If that doesn't fix it then attach the preset itself, a snapshot does nothing for me.

[Luxferre]

On 6/26/2023 at 10:51 PM, rd2rk said:

If you're using "stomp" type FX (vs pro-grade rack FX) they expect an Instrument level input, so make sure you have the Send/Return set to Instrument.

If that doesn't fix it then attach the preset itself, a snapshot does nothing for me.

Everything is at instrument level, the preset is attached up there

[rd2rk]

That's not the preset in your screenshot, but nothing about it jumps out at me as being a problem.

What are the actual external FX that you're putting in the loop?

[Schmalle]

Two things to consider:

• A stereo delay into a mono cab changes the tone due to mixdown to mono.
• Some delays have a headroom parameter to mimic input overdrive. Increase it to get rid of those artifacts.

[Luxferre]

On 6/27/2023 at 12:06 AM, rd2rk said:

That's not the preset in your screenshot, but nothing about it jumps out at me as being a problem.

What are the actual external FX that you're putting in the loop?

Sorry if it's not exactly the same as I was tweaking and trying things, puting the fx loop pre and post amp, but amp and fx loop blocks are the same, I'm not trying to mislead or anything.

Pedals I've tried: Plethora X5, Boss Rv-3, Source Audio EQ, Ibanez TS-9, Boss RC-1 and everyone of them causes the issue, the only one that worked fine was the TC Spark mini (maybe because it's a tiny circuit), that made me think it's an send/return impedance issue, since there's no option to tweak it, and it really souns like I'm runing a 30 pedal chain, tomorrow I'll try using a buffer.

 

That said, does the fx loop impedance changes depending on it's placement on the chain?

 

 

 

[Luxferre]

On 6/27/2023 at 1:53 AM, Schmalle said:

Two things to consider:

• A stereo delay into a mono cab changes the tone due to mixdown to mono.
• Some delays have a headroom parameter to mimic input overdrive. Increase it to get rid of those artifacts.

Tought of that, I tried with just amp, fx loop and cab, stereo and mono, same issue.

[rd2rk]

On 6/27/2023 at 12:06 AM, Luxferre said:

Sorry if it's not exactly the same as I was tweaking and trying things, puting the fx loop pre and post amp, but amp and fx loop blocks are the same, I'm not trying to mislead or anything.

Pedals I've tried: Plethora X5, Boss Rv-3, Source Audio EQ, Ibanez TS-9, Boss RC-1 and everyone of them causes the issue, the only one that worked fine was the TC Spark mini (maybe because it's a tiny circuit), that made me think it's an send/return impedance issue, since there's no option to tweak it, and it really souns like I'm runing a 30 pedal chain, tomorrow I'll try using a buffer.

 

That said, does the fx loop impedance changes depending on it's placement on the chain?

 

 

 

 

The FX Loop impedance is 1M regardless of its location in the chain.

Try this. Run the SEND directly to the RETURN, no FX in the loop.

Assign a FS to bypass the Loop Block. Play. The signal should be the same with the Loop Block active as it is when bypassed.

One at a time, try the devices in the loop.

Unless I'm mistaken, all of the named devices are stereo. Be sure that you're using the MONO connectors.

[Schmalle]

On 6/27/2023 at 8:07 AM, Luxferre said:

Tought of that, I tried with just amp, fx loop and cab, stereo and mono, same issue.

Ok. I misread the OP.

 

I suspect the level sent to your delays etc is too high.

 

Set Send/Return to Inst in Global Settings -> Ins/Outs to reduce the send level and/or use the controls in the FX block.

 

The FX return input impedance changes with said Global setting: Inst=: high impedance, Line= low impedance. That is only affecting the tone if you plug in an instrument directly into one of the returns. Placement of blocks is not relevant.

[Luxferre]

On 6/27/2023 at 2:40 AM, rd2rk said:

 

The FX Loop impedance is 1M regardless of its location in the chain.

Try this. Run the SEND directly to the RETURN, no FX in the loop.

Assign a FS to bypass the Loop Block. Play. The signal should be the same with the Loop Block active as it is when bypassed.

One at a time, try the devices in the loop.

Unless I'm mistaken, all of the named devices are stereo. Be sure that you're using the MONO connectors.

 

Did that, as I said in the OP, I jumped the FX loop, getting tone loss when placing the block after the amp block, not a lot but noticeable.
Today I used a buffer and the return lvl on +1dB, that worked fine, close to a not noticeable difference.

And by the way, I used mono and stereo with stereo pedals, same issue.

 

Tonight I'll setup a looper to record a video with the issue and my solution, maybe that will help someone and maybe get a better solution or a cause ;).

 

Thanks to everyone helping!

[lperry65]

I Have the same issue with the HXFX, if I use an FX Loop block, I lose tone. It thins the natural sound I get direct into the amp; I can test by pressing mode and tap at the same time and bypassing the HXFX. It's easily noticeable how much thinner the sound gets, even on a patch that only has the FX Loop block. I've tried the HXFX with two amps and get the same results, Line 6 should be able to replicate this, I've seen several posts from users having this issue. I guess if you’re really used to the sound of your amp and don’t always use affects you notice it straight away, if you always play with effects or don’t use the loop then you wouldn’t hear it.