Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Papa Jim on June 17, 2016, 07:23:45 am

Title: Want to build this FX Loop onboard my amp???
Post by: Papa Jim on June 17, 2016, 07:23:45 am
I'm adding a reverb to my 4-4-0 (trainwreck) style amp. While I'm at it I'm considering adding this effects loop. I was wondering what the 3 pots would be labeled.
Title: Re: Want to build this FX Loop onboard my amp???
Post by: kagliostro on June 17, 2016, 09:07:35 am
Quote
I was wondering what the 3 pots would be labeled.

What do you have against Send - Return - Recovery ?

--

It is an in series FXLoop

Franco
Title: Re: Want to build this FX Loop onboard my amp???
Post by: Papa Jim on June 17, 2016, 03:53:36 pm
Sounds good to me. I've never had or used an amp with a FX loop. I should have said what are they for. Lol  I assume they are for matching or setting the volume between bypassed and looped? Also to dial out any overdrive that the circuit might introduce if I didn't want it doing that?
Title: Re: Want to build this FX Loop onboard my amp???
Post by: kagliostro on June 18, 2016, 01:58:44 am
The function is to adapt the output (and input) impedance to the external units and at the same time to adapt the signal levels


if instead of a series FXLoop you use a parallel FXLoop it has also the function to mix together the Wet and Dry signal and to supply it to the following stages


Here an example of parallel FXLoop (from Merlin's book) that a friend put on his modified 5E3

click on the image for full resolution (or download it)
(http://i.imgur.com/lx0Onyg.jpg)


Franco
Title: Re: Want to build this FX Loop onboard my amp???
Post by: Papa Jim on June 18, 2016, 09:58:48 am
Thanks Franco for the explanation and schematic. Got it saved away. Putting my parts list together now. Been reading up on them and I think I'm gonna stick with my original schematic for the series Loop. Can't wait to give it a go round since I usually always have a delay in use and sometimes a little bit of compression.