Problem with 4 Cable Method and amp volume

[steveglock]

Hi folks.  I'm using the 4 Cable Method with a Fender Deville amp. The issue happens when I use my JTV 69 and when I connect a traditional guitar. The issue is: when I have the FX Loop 1 switch on (sending the signal to my Deville preamp), the volume out of the Deville is about 80% reduced compared to the normal volume. I'm testing with a preset that has no effects, 0dB output level, FX Loop 1 parameters Send and Return = 0 dB, mix 100%. Please see my setup and test results. 

 

1) setup. I have tested and retested with reliable cables.  

• Guitar -> Helix guitar/Variax In
• Helix Send 1 -> Amp Instrument In
• Amp Send (Pre-amp out) -> Helix Return 1
• Helix ¼ inch Out -> Amp Return (Power amp In)

2) In global settings, I have 1/4 inch out, Send 1, and Return 1 set to Line Level. 

3) I have tried Send/Return 2 but did not work either 

4) If I disconnect the Preamp out and Power amp in cables (signal chain is Guitar -> Variax in -> Send 1 -> Amp instrument In), I get the correct (loud) response from the amp). The issue seems to be  between my preamp out and the power amp In. However, with FX Loop 1 OFF, all my presets work great (Helix signal out through the power amp.  

 

Any ideas? Thanks! 

[rd2rk]

Unless someone else with knowledge of the DeVille has another suggestion:

 

Assign the FX Loop Block Bypass to a FS.

Assign the Output Block Level to that same FS.

Assign MIN (Loop Block Bypassed) to 0db.

Assign MAX (Loop Block Active) to whatever level it takes to compensate.

[steveglock]

Thank rd2rk! I'm hoping I have a Helix setting set wrong. But if this is something I have to live with, I will definitely try your idea. Thanks! 

 

Steve

[somebodyelse]

Hmm?

Shouldn't all the cables to and from the amp be 'instrument' level, not 'line'?

[rd2rk]

On 9/10/2024 at 5:12 AM, somebodyelse said:

Hmm?

Shouldn't all the cables to and from the amp be 'instrument' level, not 'line'?

 

Not necessarily. Unfortunately, there's no standard for FX Loops. I assume that they've tried both settings.

[somebodyelse]

On 9/10/2024 at 5:12 PM, rd2rk said:

 

Not necessarily. Unfortunately, there's no standard for FX Loops. I assume that they've tried both settings.

Well, the 'guitar in' on the amp is definitely going to be instrument level. FX loops on amps are usually either instrument level or switchable, since most punters over the decades would be using stompboxes or rackmounts, which tend to have switchable in/out levels.

Line level on guitar multifx floor units has only really 'been a thing' since the Helix came out.

Whilst I certainly wouldn't bet my house on it, I'd certainly be surprised if the loop wasnt instrument level.

 

Anyhoo, point is, if your amp is sending instrument level to a Helix expecting to receive line level, stands to reason that the level is going to be significantly down on what it should be.

Rules #1 & 2 - 'Get your ins and outs set correctly' and 'Write your presets while listening through the equipment you're going to be playing through.'

[rd2rk]

On 9/11/2024 at 3:43 AM, somebodyelse said:

Whilst I certainly wouldn't bet my house on it, I'd certainly be surprised if the loop wasnt instrument level.

 

Agreed, good catch!.

Setting the SEND to LINE level could overdrive the amp's Input, and if the amp's SEND is Instrument level and the Helix RETURN is set to LINE, it might be returning a lower signal. The Variax is a separate Input, so that could be where the problem lies.

I don't have either a Variax or a DeVille to test but setting the FX Loop to Instrument level would be a good thing to try if you haven't already.

Also, while it requires an extra block, you can always use a SEND set to Instrument and a RETURN set to Line.

Just something else to try.

 

[steveglock]

Thanks for all the good suggestions. Here are the results (not great). 

 

The Deville manual does not specify whether the FX loop is Instrument or Line. I did find a website that said they were Line level. Since you can only specify one option for both the Send and Return on the Helix, and with the suggestion above that the Send -> Deville instrument in should be Instrument, I used Send 1 and Return 2 as follows:

 

Guitar -> Helix guitar/Variax In

Helix Send 1 -> Amp Instrument In – (Send 1 = Instrument)

Amp Send (Pre-amp out) -> Helix Return 2 – (Return 2 = Line)

Helix ¼ inch Out -> Amp Return (Power amp In) – (1/4 inch out = Line)

 

No improvement. I then randomly toggled the 3 parameters and found these settings each resulted in a slightly higher output. But the result is still significantly lower than when I unplug the amp send/return cables. With these setting the output may be slightly higher, but the tone is a little distorted. Kinda nice if I ever perform in a closet. ;-) 

 

Guitar -> Helix guitar/Variax In

Helix Send 1 -> Amp Instrument In – (Send 1 = Line)

Amp Send (Pre-amp out) -> Helix Return 2 – (Return 2 = Instrument)

Helix ¼ inch Out -> Amp Return (Power amp In) – (1/4 inch out = Line)

 

Finally, I confirmed the same results using my Ibanez Roadstar guitar with the Variax disconnected. And just to test the Deville FX loop, disconnected the Helix and ran a guitar cable from Preamp out to Poweramp in - worked fine. 

 

Thanks again for your help. Unless there are other ideas out there, I think I may just abandon this approach. 

 

Steve