Delta 1010 Recapping Mods

[mtl777]

Hi:

I want to modify my Delta 1010 soundcard and one of the mods I would like to do is changing out the caps to better brands and/or better values. For this I would like to ask for your help in suggesting replacement values, especially for the coupling caps -- values that you think would be ideal and would get me quicker to the sweet spot than if I had to do a long, tedious trial-and-error process.

Here's a "component placement diagram" of one section of the A/D board of my 1010:

http://home.ca.rr.com/mtl777/Files1/...ction%20v3.jpg

The stock cap values are shown. I would particularly like to know what value you would suggest for the coupling caps C71, C67, and C61 (these are currently 47uF) and the coupling cap C21 (this is currently 10uF).

Now here's a "component placement diagram" of one section of the D/A board of my 1010:

http://home.ca.rr.com/mtl777/Files1/...ction%20v3.jpg

In particular I would like to know what value you would recommend for the coupling caps C37 and C38 (these are currently 47uF) and the coupling caps C41 and C35 (these are currently 10uF).

These are the most important ones for me, but please feel free to suggest replacement values for any caps other than these that you think would benefit from a change of value.

Your help is greatly appreciated. Thank you so much!

[mtl777]

Bump!

I was hoping someone could at least give some rules of thumb with regards to choosing ideal values for coupling caps. Like, should I try larger values than smaller first? Are larger values generally better (up to a point) for coupling caps?

Thanks!

[sangram]

Hi,

I did recap a Delta66, SB Live! and 1212m with exactly the same values as the original, just better quality (Pana FC, with BGs on the way).

I had a similar question and I decided to use exactly the same values, that way I could blame any issues on myself instead of the cap value.

Having done that I'm glad I did. I recently recapped a set of MX5021 speakers, with some of the surplus caps from the soundcard mod projects. I blindly replaced everything with 22uF caps. When going through the dead and wounded, I realised that some of the originals were 1uF, 2.2 uF and other weird values.

Shouldn't be a problem, right? Except that for about 10 seconds from switch on there is audible popping from turning the volume control (it uses a audio controller to process the volume). I guess those are those 22uF caps charging up where there were supposed to be 1 uF caps. I could mod the mute circuit to increase the turn-on delay, but I'm not going to. I like it with that quirk.

My advice would be to just get the best possible caps you can with identical values.

As to your diagrams, I suppose the caps from the DAC to the opamps are already bypassed, unless those .01s are something else. I don't know how much of a benefit you're going to get out of new caps. I still have to figure out why those caps are so huge. My 1212m also has 47uF caps there. The opamps can't be that big a load.

Are your numbers right? The picture says 37 and 31, your post says 37 and 38

[sgrossklass]

Choosing electrolytics ten times as large as absolutely necessary (or larger) in coupling cap applications has been common practice since at least the Jung/Marsh article way back in 1980. Film caps in the same position can generally be a good bit smaller.

An important factor in coupling cap selection is the amount of DC voltage dropping over it. If it's much less than 1 V, one is generally best off with low-leakage 'lytics if nothing else fits. (You generally don't want your audio currents to be used for stuffing holes in Al2O3 layers. This also is why one would prefer larger rated voltages - the thicker the oxide layer, the longer it takes for it to get leaky without bias voltage applied.) If you can fit a metallized polypro of reasonable capacity (like 3µ3) in such a situation, then go ahead, of course.

"Power supply" electrolytics (FCs belong here, for example) may have relatively high leakage currents, as this is not critical in their intended application (namely supply voltage filtering - who cares about a µA or two if the load draws at least 1000 times as much?). I would guess that they work reasonably well as coupling caps as long as there's a decent DC voltage (like several volts) dropping over them.

All this should make clear that "blind" recapping may very well backfire.

[mtl777]

Hey guys, thanks for all the great info!

Originally posted by sangram
Are your numbers right? The picture says 37 and 31, your post says 37 and 38

Oh my bad, the 38 should be 31. Thanks for the correction!

[cuibono]

Hi MLT777-

Search this forum for other soundcard upgrades. Soundcards tend to have basically the same analog in/out sections, so mods are interchangeable. I highly recommend adding larger electrolytic caps to the PS filter. I did it on my 1010LT and it helped a lot, more dynamic bass. Supposedly changing coupling caps and opamps changes things some, but the PS caps make the biggest difference.

Look around, someone took some photos, making it really clear how to do the changes.

Good luck..

[mtl777]

Originally posted by cuibono
Look around, someone took some photos, making it really clear how to do the changes.

I'm very interested in this. What soundcard was it? Do you remember the author or maybe a search string that would help narrow my search? Thanks!

[Ryssen]

Try Emu1212m