Cal'ing a DBX 162

An original one to be exact. I have one headed my way that will likely need at least a small tweak, from the look of it. I remember someone asking on the old forum, but I didn't archive it, thinking I'd never have a need for such information.

Only now I think I might.

Nothign in the search results pointed me in the right direction...help?

-dave

> least a small tweak, from the look of it.

If it is the same 162 as mine (DBX re-used too many numbers), it is very unlikely to "drift out of calibration". If the meters don't sit at zero, check the power supply rails right-off.

Picture -- Schematic

That'd be the one...the REAL 162, before they made it purple with extra buttons and knobs :wink: AFAIK, there are only two models of 162, the black one we're talking about, and the new 162SL that's really just a scaled down version of the 160SL.
The only reason I asked is because the picture I got was of a unit that had definately seen a hard life. Is the PS a common failure point on these old beasts? Anything else to watch out for except scratchy pots?
It should be a nice compliment to my 164, Symetrix 501s, GSSLs, and the 2 Ashlys I have coming, and a great way to add the color that my RNC seems to lack (not that that's a bad thing).

Thanks

-dave

Symetrix 501, eh?

I have a couple of these that I really like. Can you compare/contrast them with some of your other comps?

One of mine has been modded with new OAs and a larger output cap to fix some low freq rolloff in the original ckt.

Ooo! That 162 is cool!

Thanks!
Charlie

> the picture I got was of a unit that had definately seen a hard life.

Hold it together with duct tape. If the PCB is cracked, the whole beast is a paperweight; otherwise cosmetic flaws are trivial. (Busted meters are a REAL problem: you can't replace those.)

> Is the PS a common failure point on these old beasts?

No, but I had the idea you thought it needed calibration. If the meters sit where they are supposed to (0dB in GR, below -40dB in Level with no signal, and bouncing with signal), any trimming you do inside is likely to make things worse. In fact I think the only real "trim" sets the "4:1" mark on the ratio knob to really be 4:1, and that only matters to testers. If you just want to use it, the numbers don't have to be right.

But if it is reading wrong in both channels, then the power supply is the most likely suspect. It is the only part that works hard.

Scratchy pots? The pots don't pass audio, they set DC voltages and have caps on them to filter any pot-glitch. They'd have to be cracked right through to be a problem, and you could hack-in some Radio Shack pots and let it live again.

Are these things REALLY selling for $500-$1,000???

I have a busted meter. I wish I could find a replacement, grumble grumble.

dave

Dave,

Can't the meter be repaired?

If not, try to find a meter that will fit mechanically and that has the right sensitivity.

Open it, and bend the zero-return spring so that it rests at the right position...

Jakob E.

Ive got to take it apart, it will move forward towards the plus side of the scale, but will not move to the left side of the scale. Just another one of those annoying things to fuck with, I never use the meters on there I just want to fix it so I can sell it really, the LED is all Ive ever looked at on those.

dave

[quote author="PRR"]Hold it together with duct tape. If the PCB is cracked, the whole beast is a paperweight; otherwise cosmetic flaws are trivial. (Busted meters are a REAL problem: you can't replace those.) [/quote]Actually, a cracked PCB would give me a good excuse to make a new one and transplant the parts :wink:

[quote author="PRR"]If you just want to use it, the numbers don't have to be right. [/quote] I rarely actually look at the meters...I just twiddle knowbs until it sounds nice. Art isn't about science.

[quote author="PRR"]But if it is reading wrong in both channels, then the power supply is the most likely suspect. It is the only part that works hard. [/quote] Hmmm. Sounds like I might want to work on that a little. Not too much, but maybe beef it up a little. IO like mygear to last forever, no questions asked.

[quote author="PRR"]Are these things REALLY selling for $500-$1,000???[/quote]Depends on where you look. The one I just picked up wasn't that high, but it would have been if I hadn't known the guy selling it. Anything with the DBX logo and a hint of vintage-ness is way overpriced these days IMHO. There are people getting close to $400 for a 160x! It's a little bit crazy if you ask me. Hence my quad of GSSLs :wink:

-dave

[quote author="SonsOfThunder"]Symetrix 501, eh?

I have a couple of these that I really like. Can you compare/contrast them with some of your other comps?

One of mine has been modded with new OAs and a larger output cap to fix some low freq rolloff in the original ckt.

Ooo! That 162 is cool!

Thanks!
Charlie[/quote]
The 162 is indeed very cool. I've used them in the past, and if I could have a couple of 162s and a few 1178s I'd be a very happy man.

My 501s are both dead stock. I'm not very good at describing the "character" of a piece, but I like them on kick and especially on bass. I've used them in stereo on OHs, but I like my RNC more for that. They don't do a good crush on a signal (that's what the 164 is for) but they do add a very nice squished sound. I used one with great success on backing gtr recently. I crushed it, then let up until it didn't sound grungy. I think I ended up around 10:1 (actual..the markings are only estimates in my experience). I tried one on female vox once, and it was fine, but nothing I'd describe as 'special'. Generally, I like them for low frequency stuff. I've heard they're excellent on Trumpet as well, but that's 3rd hand info.

-dave