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Topic: Session 400 Adding Eff. Loops |
Bill Paisley
From:
Athens, TN, USA
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Posted 17 Jan 2005 7:00 am |
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| I have an early 80s model Session 400, and was wandering if it's possible to add effects loops to the circuit. Bill Paisley [This message was edited by Bill Paisley on 17 January 2005 at 07:02 AM.] |
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jim milewski
From:
stowe, vermont
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Posted 17 Jan 2005 1:35 pm
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| I added one to my Session 400, right after the first transistor on the "out side" of the coupling capacitor, really can't say it made much of a difference though, maybe I should have done it just a little further down the line |
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Gary Carriger
From:
Victoria, Texas
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Posted 17 Jan 2005 4:42 pm
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Bill,
I have a '73 Session 400...and while I had in back at Peavy for some other repairs had them remove the spring reverb circuitry and add a pre-amp send and return. It can be done...but I can't tell you how.
Gary |
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Ken Fox
From:
Nashville GA USA
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Posted 19 Jan 2005 12:12 pm
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I got this idea from another Forum member. You could easily add a "preamp out"
and "power amp in" to the amp. The preamp out put can be picked up right from
the cable that plugs into to power amp board. Without adding any holes to the
amp you take advantage of input jack # 2 and use that as the preamp out, then
route the signal back to the jack on the back that was a "booster amp" jack (a
sample signal from the final output stages is there now, seldom used). A
"power amp" in jack could be located there (a jack with normally closed
swithing contacts that allows the preamp signal to pass to the power amp when
nothing is plugged in there.
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Bill Paisley
From:
Athens, TN, USA
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Posted 20 Jan 2005 9:21 pm
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| Ken,thanks for the article. That sounds like a good solution. Bill Paisley |
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Dennis Detweiler
From:
Solon, Iowa, US
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Posted 21 Jan 2005 6:22 am
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If you were wishing to patch the session 400 into a tube head for added amplification, would it be best to add a "preamp out", or just use the existing "booster amp" output? Or, maybe add a "line out"?
I think the "booster amp" output was made to add a slave head. But, the signal was a little stout if I recall?
DD |
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Brad Sarno
From:
St. Louis, MO USA
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Posted 21 Jan 2005 8:19 am
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Hey Ken, you could just use the booster jack and use a stereo jack for send/return and make a simple Y-cable for the FX loop. It may keep the hookup neater. My gripe with FX loops is that you send the entire signal thru an FX unit often subjecting it to crappy electronics and also mediocre A/D and D/A conversion. In a Session 400, that discrete signal path is so pure you'd almost hate to pollute it with cheap signal path and digtal crud. The parallel sidechain FX buss like the way the spring reverb gets mixed back in is a cool way to go for FX because you preserve the pure path. Maybe working the loop into the reverb send/return path is a better mod. Just a thought.
Brad |
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Bill Paisley
From:
Athens, TN, USA
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Posted 21 Jan 2005 11:57 am
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| I don't know if I was clear on what I wanted to use the Loop for. Mainly to just patch in my volume control or a digital delay. I assume the send should be right after the preamp stage. |
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Ken Fox
From:
Nashville GA USA
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Posted 22 Jan 2005 8:32 am
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ACCORDING TO THE OLD SESSION 400 MANUAL IT IS A 1 VOLT SIGNAL LOOKING FOR A MINIMUM 10k OHM INPUT IMPEDANCE. IT IS UNBALANCED, SO YOU MIGHT GET SOME GROUND LOOP HUM
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Ken Fox
From:
Nashville GA USA
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Posted 22 Jan 2005 8:37 am
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My experience is the preamp signal is usually to hot for a volume pedal. The pedal loop on a Nashville is quite a few gain stages back. For the Nashville 400:
Patch output is 0.2 volts at 1k ohms or greater
Patch input is 0.2 volts 220K ohms [This message was edited by Ken Fox on 22 January 2005 at 09:26 AM.] |
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rpetersen
From:
Iowa
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Posted 22 Jan 2005 6:47 pm
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Brad - I have a 75 session 400 without a reverb tank - Are you saying that I could use the in and out of the reverb patch to put in something like an RV3 - and would I have to know which was in an out?????
------------------
Ron Petersen &
The Keep'n Tyme Band
Mullen Universal 12 - 1975 Session 400 - Nashville 1000
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Dennis Detweiler
From:
Solon, Iowa, US
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Posted 30 Jan 2005 6:46 pm
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The input impedance on my Peavey Classic 50/50 is 250K ohms. The minimum input level is 1V RMS, 0 dBV. Can I patch from the Booster Amp output on my old Session 400 into the Classic 50/50?
Thanks
Dennis |
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Dennis Detweiler
From:
Solon, Iowa, US
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Posted 30 Jan 2005 7:14 pm
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Scratch my last post. I found the info in searching previous posts.
DD |
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