DEQ2496 Capacitors upgrade question

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tower2010

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Joined 2010
Hello:

I would like to make a capacitors upgrade on the DSP board (AKM chips, etc). I have several Sanyo OSCON SEPC 470uf 16V in my drawer. Do they have too much capacitance? The actual DSP capacitors are 10uf.
Would I have some problem with the experiment?

I'm new in the DIY, so sorry if the question it's very basic.

Best Regards
 
M

mterbekke

Member
Joined 2009
Hi Tower,
I think it`s best to stick with the original values. Yours might work, or not. Biggest problem is when you get problems that are random. So later on you start asking yourself all kinds of questions what the problem might be. So, better to stick with the 10uF!
 
Pano

Pano

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Well... let me see if I remember which ones. :)

I did all the power caps from the regulator to the DAC and ADC chips, C2, C3, C4, C5 C6, C8, C10 - C17, C55, C26, C27. I don't think I did the VRef pins of the DACs. I'll double check that.
It was certainly cleaner sounding and had much more subjective drive dynamics and "oomp". Not surprising, as I use a transformer output directly from the DAC so the bigger value, lower ESR caps seemed to help a drive the output better.

Tests I've seen on the OSCON caps indicate they may be even better than the Panasonic FM. The FM are easy and cheap for me to get at Digikey. There are a number of folks doing cap upgrades to the DCX as the stock caps are pretty cheap community items. The DEQ is so similar that the same upgrades apply.
 
Pano

Pano

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Or the OSCON, they seem to be really good in digital noisy circuits.

Unfortunately, I looked in my parts bin today and have only 1 of the correct value caps left. :( Will have to order more of the FM series in 47uF. Nice that they are the same size as the stock caps, they fit right in. Will report and try to provide before & after measurements once the new caps are in place.
 
MurphyUHF10

MurphyUHF10

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Joined 2010
Pano said:
Well... let me see if I remember which ones. :)

I did all the power caps from the regulator to the DAC and ADC chips, C2, C3, C4, C5 C6, C8, C10 - C17, C55, C26, C27. I don't think I did the VRef pins of the DACs. I'll double check that.
Click to expand...

Hi Pano,

Just in the process of ordering these caps..

Did you replace with the same values?? What is the "47uF" you guys keep mentioning?? According to the schematic, this is quite diffferent to whats actually being used on the DSP board..

Thanks!
CM
 
Pano

Pano

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The caps on the PCB are cheap 10uF (10 microFarad) electrolytic. I've replaced them with Panasonic caps of the same physical size but a larger capacitance. I used 47uF. The Panasonic FM series are also high quality caps with great specs. Bigger value, higher quality.

I think that having a larger values, higher quality cap right next to the chip helps the sound quality. Some of the others are at the voltage regulators that feed the chips.
Think of it as a cheap little power supply upgrade that actually works.
 
MurphyUHF10

MurphyUHF10

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Joined 2010
okay thanks Pano,, if it wont hurt, I'll get the 47uF Panasonic FM as well..

But having inspected the board last night,, it seems they are not all 10uF..??
The ones near the V regs appeared to be other values?? (Yes, the ones near the DAC chips are 10uF),, so just use 47uF across the board?? (pun intended)

Thanks again!
CM
 
MurphyUHF10

MurphyUHF10

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Joined 2010
Pano said:
The caps on the PCB are cheap 10uF (10 microFarad) electrolytic. I've replaced them with Panasonic caps of the same physical size but a larger capacitance. I used 47uF. The Panasonic FM series are also high quality caps with great specs. Bigger value, higher quality.

I think that having a larger values, higher quality cap right next to the chip helps the sound quality. Some of the others are at the voltage regulators that feed the chips.
Think of it as a cheap little power supply upgrade that actually works.
Click to expand...


Hi Pano :)

Not to go on too much about this,,, but..

Wouldn't it be better to replace the stock 10uF with 22uF/50v FM's instead of 47uF/25v FM's,, that way you stay closer to the actual values originally used??

I can get both FM's locally, and the 22uF (EEUFM1H220) are exactly the same size as the 47uF (EEUFM1E470), and only differ in ripple current and impedance from each other..

Also, C56, C59, etc.. are 100nF,, did you also use 47uF for these ones??

I just assume that's its best to stick as close as you can with original values..?

Thanks!
CM
 
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Pano

Pano

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In this case - power decoupling - it did not hurt to go up to 47uF. I thought it might lead to trouble, but it did not that I could hear, measure or see on the scope. In fact, it sounded better than stock. 47uF is simply the biggest value that would fit right in. If you feel happier with the 22uF, why not? There has to be a point of diminishing returns, 22uF might be it.

All I replaced on the DCX were the 10uF caps on the analog and digital power rails for the DACs and ADCs, nothing else. Leave the other ones alone, unless you know what you are doing.
 
MurphyUHF10

MurphyUHF10

Member
Joined 2010
Pano said:
47uF is simply the biggest value that would fit right in. If you feel happier with the 22uF, why not? There has to be a point of diminishing returns, 22uF might be it.
Click to expand...

So it's a matter of the biggest value that will fit, as apposed to matching the same value?? Why wouldn't they have just used a higher value if it would yield a better result?? Anyway, I'll take your word for it :)

Pano said:
All I replaced on the DCX were the 10uF caps on the analog and digital power rails for the DACs and ADCs, nothing else.
Click to expand...

I't's just that in a previous you mentioned "C55",, which is a 100nF surface mount?? I counted 21 of the 10uF/25v caps in total,, but I'm not sure which ones exactly are "analog and digital power rails for the DACs and ADCs", I just thought you changed all of these to 47uF..

Thanks again!
CM
 
Pano

Pano

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MurphyUHF10 said:
Why wouldn't they have just used a higher value if it would yield a better result??
Click to expand...
Cost, pure and simple. 10uF is "good enough" for the intended use. Price point is another reason to use cheap caps. If they used all premium parts, the unit would cost a lot, lot more. That's the nice thing about DIY upgrading. You can improve a few critical points at little cost.

I'll look again at the schematic this evening, I probably goofed on one of the cap numbers.
 
MurphyUHF10

MurphyUHF10

Member
Joined 2010
Pano said:
Cost, pure and simple. 10uF is "good enough" for the intended use. Price point is another reason to use cheap caps. If they used all premium parts, the unit would cost a lot, lot more. That's the nice thing about DIY upgrading. You can improve a few critical points at little cost.

I'll look again at the schematic this evening, I probably goofed on one of the cap numbers.
Click to expand...

Ok thanks mate.. I'll get the "biggest that will fit" as well,, which is the Panasonic EEUFM1E470 (47uF/25v)..

Maybe I got confused regarding cap nunbers?? I am referring to the DCX,, but just realised this thread is about the DEQ :)

Ta
CM
 
MurphyUHF10

MurphyUHF10

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Joined 2010
Ok..

Have finally replaced the stock 10uf/25v caps on the DSP board of my DCX with 47uf/25v Panasonic FM series..

It's hard to say wether I'm noticing much.. I don't know exactly what to look (listne) out ofr when replacing supply rail filtering caps,, but I what i do notice is a little bit of a 'hard edge' removed, which sort of opens up some space between the instruments..

Thanks..
CM
 
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