Drawmer dl251

[atomdog]

Hi all,

Just wondering if anyone is able to highlight the audio signal path in the attached schematic.

I don’t want to waste money on replacing anything that isn’t.

If anyone has any general mod suggestions would be appreciated. It sucks none of the opamps are socketed

Thank you

 

[jensenmann]

What´s wrong with it?

 

[atomdog]

What´s wrong with it?

Oh nothing is wrong with it - I’ve just over the years accumulated lots of surplus parts that I could use.

It’s quite a early model so could probably do with replacing the lytics of which is mainly used.

 

[Migs 31]

I don’t want to waste money on replacing anything that isn’t.

If anyone has any general mod suggestions would be appreciated. It sucks none of the opamps are socketed

It's a good Drawmer! They used to be the benchmark around here, you know.
They are still some of my most transparent and useful Comps & Gates.
Changing the Op-amps won't change much on this baby, I think.
I did butchered a newer DBX last year, shitty sound, totally different story.

If it ain't broke, don't try to fix it.
If it sounds Terrible, then it's a different story.

M

 

[atomdog]

It's a good Drawmer! They used to be the benchmark around here, you know.
They are still some of my most transparent and useful Comps & Gates.
Changing the Op-amps won't change much on this baby, I think.
I did butchered a newer DBX last year, shitty sound, totally different story.

If it ain't broke, don't try to fix it.
If it sounds Terrible, then it's a different story.

M

Yes, I definitely won’t mess about with opamps seeing as they are not socketed.

Yep you are right - I’ll probably just replace obvious culprits like in/out caps, standard values I happen to have and forgo anything I need to buy.

 

[jensenmann]

Recapping is a good idea as it makes gear work more reliable.

These Electrolytics are in the audio path: C1, 3, 8, 9, 15, 17, 31. Except C8+9 they are rather smallish dimensioned. Increasing them could clear up the low+lowmid range by lowering the phase shift, but there are no wonders to be expected, just a bit more definition. Especially C15 could benefit from being a lot larger (22-100uF). But having owned and used a DL251 for 2 decades I know that it sounds just fine as it is, though. If you decide to recap it using electrolytics then you could use bypass caps (film caps with 10-100nF) parallel to the electrolytics in the signal path. Solder them underneath the PCB. Try one channel and compare it with the untreated channel to find out if it improves anything for you.

Another option is to stick with the original 4,7uF value but change to film caps. Wima MKS2 film caps will most likely fit the available space. In case of C1+3 it´d make sense to match them to retain a good common mode rejection in the lowend.