Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: shooter on April 12, 2019, 11:45:20 am

Title: FX midstream
Post by: shooter on April 12, 2019, 11:45:20 am
Looking for electronic “expectations” for fx inserted in the signal path vs in front of amp.
Ideally a bullet proof example to steal.  Every time I talk with musicians my eyes glaze over.  My reply, do they work in front of my amp?  YES it loves pedals, ok find a smart guy to cut up the amp.
The customer has a zero loss, isolated jacks,  fx “kit” without docs. And wants it installed.

What Vac should I aim for “sending”, what Vac should I expect “returning”?

I’m only able to test with sig gen n scope, which in my world is “standard”,  all the fuzzy, whaaeee, crunchy, stuff just glazes the brain!

Thanks as always
dave
Title: Re: FX midstream
Post by: 2deaf on April 12, 2019, 04:59:04 pm
What Vac should I aim for “sending”, what Vac should I expect “returning”?

The Home Recording Line Level is -10dBV, which is 0.45V peak.  This is the number that I have been using for send level designs for the last 35 years.  I would expect the same level coming out of a line level FX device.  This will need to be amplified to get the same level you started with before you reduced it for the FX send.

Stomp boxes are usually guitar level which is more like 0.1Vp.  Hot pickups with a heavy hand can still reach line level, though. 

Title: Re: FX midstream
Post by: shooter on April 12, 2019, 06:26:12 pm
thanks 2deaf, I got a 100 schematic examples, no data  :laugh:

Quote
This will need to be amplified to get the same level you started with before you reduced it for the FX send.

that's my rub, why I don't add them in builds.  some pedals work, some don't, some cause....
since it's just 2 jacks I'll install the jacks making sure it ain't on me if that "feature" doesn't work as expected.