serial loop bleed

[joeydego]

I have a fairly new triple rec. Is there a mod commonly done to completely eliminate the effects loop bleed? It's really not much, but its there.

 

[domct203]

I have a fairly new triple rec. Is there a mod commonly done to completely eliminate the effects loop bleed? It's really not much, but its there.

Unfortunatly no, there is no easy mod for this. The bleed happens between the 2 triodes of V4, the FX Loop Driver/Buffer. A 12AX7 is really two triodes (tubes) in one bottle, and the bleed is between the triodes for the FX Send and FX Return buffer stages even though there is no actual physical connection between them. You would need to relocate either the send or return buffer to another triode, which would require installing another tube and the related curcuit.

Welcome to the beautifully imperfect world of tube amplification !

Dom

 

[joeydego]

I have a fairly new triple rec. Is there a mod commonly done to completely eliminate the effects loop bleed? It's really not much, but its there.

Unfortunatly no, there is no easy mod for this. The bleed happens between the 2 triodes of V4, the FX Loop Driver/Buffer. A 12AX7 is really two triodes (tubes) in one bottle, and the bleed is between the triodes for the FX Send and FX Return buffer stages even though there is no actual physical connection between them. You would need to relocate either the send or return buffer to another triode, which would require installing another tube and the related curcuit.

Welcome to the beautifully imperfect world of tube amplification !

Dom

Well that's certainly not good news! What exactly is the point of having a tube effects loop, then? I wonder if it would radically change the sound of the amp if it weren't, everything else staying the same. Perhaps a future feature could be 2 loops if that's even possible.

 

[screamingdaisy]

The FX loop bleed is only an issue at very low volumes where it can cause a phasing effect. At anything above that it sounds fine.

Not a great answer if you primarily want to use it at bedroom volumes, but it is was designed primarily as a professional stage amplifier and that is the roll for which it shines.

 

[joeydego]

Does this latency physically happen IN the tube itself or in the circuit? Could a device be inserted in the circuit to effectively try and match the latency of digital effects by hand/ear? The funny thing is this head allows you to drop tubes out of the mix all over the place for tonal changes, but not for a common issue like this.

 

[screamingdaisy]

The latency goes away if you bypass the loop, either on the footswitch or using the hard bypass on the rear of the amp.

 

[joeydego]

The latency goes away if you bypass the loop, either on the footswitch or using the hard bypass on the rear of the amp.

Yes I understand, but my reason for asking is I'd like to use effects at reasonable volume with zero phase issues. Getting rid of the loop defeats the purpose of the loop!