Reverb pan for Peavy Studio Pro 40

[Mickeydam]

Hello all.  New guy, here.  Cool place.  I just picked up a crusty Studio Pro 40 last week and am loving the sounds to be had.  Needs a good cleaning, and de-ox on the pots and connectors.  The only other issue I see is the reverb, which introduced a volume drop and gnarly distortion as I dialed up the control.  I haven't tried to troubleshoot the issue yet, but if it comes down to the reverb pan itself does anyone know what model it would be?  It's about 9" long, so I'm thinking perhaps an 8eb unit, but I'm not sure.  I've sent email to Peavey on it, but haven't received a reply.  Thanks for any help.

[Mickeydam]

Just heard back from Peavey and of course they're just giving me their part number because they want me to order the pan from them for $30 

[Mickeydam]

Hmm.  Just saw another discussion board where Enzo answers a similar question re: a Delta Blues.  Looks like the 8eb is the one I want.

Never mind 

[J M Fahey]

Just heard back from Peavey and of course they're just giving me their part number because they want me to order the pan from them for $30 

Did you expect anything else ? 

[Den.]

Before you start ordering $30 reverb pans, take the pan out of the amp and look at all the connections for all of the wires. Some of the tiny coil wires are routed behind strips of metal and are susceptible to being chaffed and even cut.

[Enzo]

First, forget the gnarly distortion aspect, do you get the reverberant effect, no matter how crappy?  If so, the spring unit is probably working.

The circuit is simple, one 4558 IC doing both drive and recovery.   A replacement reverb pan would need to be the EB type.   4,8, or 9 would be a matter of choice and the amount of space inside.  You can use a full size pan if there is room for it inside.  Otherwise, yes, the 8EB2C1B.   But I think the ICs are socketed anyway, so I would probably fight distortion by trying a new IC.

As to selling you "their" reverb pan for $30, did that amount include shipping?   Most places shipping will be at least $10-15 on top of the selling price.   You call PV for a part, they tell you what they have.   If you call a Ford dealer and ask about a water pump, they likely won;t suggest you call NAPA and buy a fake one for cheap.   SO maybe AES sells pans for $18 or something, but add shipping to that.   Peavey sells you the parts for their products.  Try calling Marshall or Fender or Behringer on the phone and asking them to sell you a part.

[Mickeydam]

Before you start ordering $30 reverb pans, take the pan out of the amp and look at all the connections for all of the wires. Some of the tiny coil wires are routed behind strips of metal and are susceptible to being chaffed and even cut.

Yep, I need to spend some time taking it apart and investigating.  I'll pay special attention to that, and thanks!

[Mickeydam]

First, forget the gnarly distortion aspect, do you get the reverberant effect, no matter how crappy?  If so, the spring unit is probably working.

The circuit is simple, one 4558 IC doing both drive and recovery.   A replacement reverb pan would need to be the EB type.   4,8, or 9 would be a matter of choice and the amount of space inside.  You can use a full size pan if there is room for it inside.  Otherwise, yes, the 8EB2C1B.   But I think the ICs are socketed anyway, so I would probably fight distortion by trying a new IC.

As to selling you "their" reverb pan for $30, did that amount include shipping?   Most places shipping will be at least $10-15 on top of the selling price.   You call PV for a part, they tell you what they have.   If you call a Ford dealer and ask about a water pump, they likely won;t suggest you call NAPA and buy a fake one for cheap.   SO maybe AES sells pans for $18 or something, but add shipping to that.   Peavey sells you the parts for their products.  Try calling Marshall or Fender or Behringer on the phone and asking them to sell you a part.

Hi!  Speak the Devil's name and he appears    j/k
Re: the distortion, replacing the 4558 IC in the reverb circuit (U3) with a known good part was the first thing I tried and there was no change.  It's hard to tell if there is any reverb going on for the distortion.  I haven't had time to explore the circuit further, check for cold solder joints, etc.  It's a small amp and I'll need to take out the chassis and the speaker before I can get the pan out for inspection.  I'll reply back to their parts dept. and ask re: the shipping for the pan.  That's a good question!  I was really just trying to get my ducks in a row in the event that I needed to buy a new pan, and you've definitely helped with that.  Thanks, Enzo!

[Enzo]

SO if you turn the reverb down the amp sounds fine? 

You turn up the reverb control it sounds bad?

SO isolate the problem.  If the above is true, then something before the reverb control is wrong.  Unplug the reverb cables.  Now what happens when you turn up the reverb?   And remove the reverb IC, now what happens?

[Mickeydam]

SO if you turn the reverb down the amp sounds fine? 

You turn up the reverb control it sounds bad?

SO isolate the problem.  If the above is true, then something before the reverb control is wrong.  Unplug the reverb cables.  Now what happens when you turn up the reverb?   And remove the reverb IC, now what happens?

Yep, turn the verb to zero and amp sounds fine.  Unplug verb pan cable and also sounds fine regardless of how much I tweak the verb control.  I'll try popping the IC and post the results.

[Mickeydam]

Finally got time to take the amp apart to get to the reverb pan and found the problem.  The black wires inside the pan going to both input and output were snapped off.  I think one or both were still making an intermittent connection leading to that distorted sound.  Yesterday I noticed that after I moved the amp to another spot in my room, the reverb control no longer worked at all, no verb or distortion, so moving it probably nudged wire(s) out of contact.  I'm going to try soldering them back on.  Not much slack in one of the wires, though.

[J M Fahey]

Fine.
I think you found the actual problem.
Intermittents are a pest, mainly because because you want to correct them, they work properly or do something different than expected.

[Roly]

These wires breaking are a very common problem with all springline reverb "tanks" because the inner assembly floats on springs so they flex a lot.  Find some fine-ish wire with heaps of fine strands, make a little spring pig-tail out of it by wrapping it around a pencil or similar, then use it to extend the coil wires.

[Mickeydam]

These wires breaking are a very common problem with all springline reverb "tanks" because the inner assembly floats on springs so they flex a lot.  Find some fine-ish wire with heaps of fine strands, make a little spring pig-tail out of it by wrapping it around a pencil or similar, then use it to extend the coil wires.

I like that idea, Roly.  Thanks!