peavey unity 2000. 16 ch. mixer. early 90's

[blaise]

not sure how noisy these things are.
but when i bring the mains up to about -3. with all channels
empty at about 0 to +3. i'm getting a good amount of white noise
doesn't seem as bad with monitor outs.
could probably figure this one out without a schematic but it would be nice
to have one anyway.

[Enzo]

As with any Peavey product, contact customer service at Peavey and ask for the schematics.


If the board is quiet with all the channel faders down, and then each channel adds a little more white noise - that is no one channel is a lot noisier than the others - then it is probably normal. Especially when considering the volume levels we are setting.

You can probably update the op amps in the input stages. A 5532 has a lot less noise than the 4558s, but it also draws twice the current. So a few 5532 in place of 4558 is OK, but a whole board fill of them might overtax the power supply. if you can find a premium op amp that doesn't draw excess current, go fo it. Newer generic types like 4580 might be quieter than the 4558s. Simple enough to try in one channel and see.

of course once you figure out what you have to go through to get at the innards, you may decide to live with it.

[blaise]

thanks for the opamp suggestions, i'll do some research.
opening it up (yuck).
but i also have a slider to replace,
so i have to go through the ordeal anyway.

[Enzo]

PV should have your slider.

[blaise]

already ordered it.
hopefully they send the right one.
last time i ordered a slider for an old mark III bass amp
they sent wrong one. it had a longer throw to it.
matter of fact i better look for that, it may be what i need now.
started the disassembly process today, all those plastic buttons on the back
were having fun now ! yeeehaw.

[blaise]

well i finished replacing the bad slide pots on this thing. what fun the disassembly process was, i shoulda ordered more new plastic clips. after breaking about 12 of them, i got wise and built a removal tool. but i dont want to take the thing apart ever again.
replaceing the two opamps at the master vol stage cured the minor hissing problem. still not super quiet but more than acceptable for my means.
if any one wants a pic of the tool, let me know. basically two pieces of sheet metal with half moon cut outs, on the tip of a pliers. ( it works )
use a ball point pen of the appropriate size with the ink cartridge removed
for the board side of the clips. just push it on to compress the retainer tabs.
same type plier tool but bigger for the xlr beauty rings. ( bezels )

[J M Fahey]

Hi.
Please post a couple pictures of your separator-removing tool.
It sounds very ingenious, we always need things like that.
I've had to use long nose pliers and , believe it or not, toothpicks, to keep those plastic teeth open.

[Enzo]

A very simple tool is a piece of tubing. I have several of these, some are brass tube, and some are plastic tube. Doesn;t matter. You can get styrene plastic tube or brass tube in the small sizes at hobby stores.

I just measured mine, and the inner diameter - the hole up the middle - is about 4mm or maybe 5/32". It is not critical, but it needs to be about that size inside.

Looks like my brass one is 3/16" OD, and the plastic 1/4". The Outside Diameter doen;t matter, but those sizes will have about the right size inner hole.

Just shove it down over the plastic post and barb. That squeezes the barb into the shaft diameter. Now just apply upwards pressure to the board. The post will clear the hole, and the tube will fall off as the post disappears.

I keep the thing near me, but if I only have one or two, I usually do it with small pliers.

Back when I was into serious "professional field service" work, I used these a lot to release boards. Some of the connector/mounting hardware makers had official release tools. They cost a lot more than a hunk of tubing, but they often gave them out at trade shows. Think of those little plastic screwdrivers with a magnet on the other end and a pocket clip, and some company name printed on the side. Except these had a small length of tubing sticking out the handle instead of a screwdriver blade.

[kirby]

12-years on, I hope somebody remembers something about the Unity 2000. Are the plastic retainers sacrificial? I have removed everything that I can see that will pull or screw off and the top and bottom still seem firmly attached.

[Enzo]

It has been years, but if I recall, the top panel has to come off, so EVERY knobs comes off, and a slew of tiny 4-40 screws between the knobs. All those jack nuts, the screw in the middle of the four RCA jacks, The end caps have to come off so the bottom front molding can slide out the end. Urge it along with a mallet if needed. There is a strip alaong the rear too.

MAKE A CHART as to knob color

If I am right, you pull the top panel and you are looking at circuit board. Look on underside bottom panel and see black circles, those are the plastic posts. Back on top, the board is held buy all those posts, and follow what I described in my last post to free the board.

[The Dude]

............MAKE A CHART as to knob color............

That's a good tip. If you forget that, you can do what I often do and use a Google image search to see what color knob goes where. I used to make charts, but don't bother anymore since it's so easy to find pictures.

[Enzo]

Sure. But the chart only needs one channel for the channels, and then a simple master section. Takes a couple minutes. And it reinforces making charts. Guy writes in asking which color wire goes where on some odd model of something because he "forgot." Far fewer pictures of those online.