AD825 module from LC Audio

[gromanswe]

And drinking Swedish Water,
PREVENTS your posts
from being
EMPTY one-liners WITHOUT SUBSTANCE
that wouldn't contribute with
anything CONSTRUCTIVE.

[Variac]

As opposedto multiliners without substance?

[gromanswe]

That balances my posts without substance.

[raul_77]

Hi all,

In www.Selectronic.fr you have the more cheap AD825 that I know.

Happy days

Raúl Couto

[Wombat]

To add a small bit of substance.

I have a Sony digital processor EP90ES
around here that has 4 OPs in the filtering
stage and 1 in the exit. I still can´t believe
Sony uses Mitsubishis 5218A types, i think
just to save money cause all channels together
need 15 OPs.

So i looked what SO-8 types i could get. I was
able to get some OPA2134UA. I only modified the
Front channel. First i switched the 4 OPs into
the digital filtering section and the result was
amazingly better! Very good imaging and a very
precise bass.

(i use my Burr Brown PCM63P-K with OPA627 as
reference so far)

So i thought i throw in the last one into the
exit and a new listening feeling will come in.

But to my surprise "nearly nothing" has changed,
nothing for better.
May be due to the capacitors around!?

Thats why i think only switching to ones with
better specs into an existing piece doesn´t
always mean it gets better!

btw. i will try a 5532 in the exit as soon i
can get my fingers on a SO-8 version.

Wombat

[Bom]

Thank you everybody for your good opinions.

Here is my understanding. I can replace the 5534 with any single opamp which has same leg (DIP, I guess). Not talking about the difference in sound, all opamp will work properly by doing so right? I mean without any other mod.

The website Wombat recommended is very useful but currently I don't have time to read all topics. I will have time to read them all by this weekend.

Thanks

[morsel]

For single SO8 opamps you can use a different adapter:

http://brndog.com/so8.html

Peace gromanswe, just didn't want bom to run off without doing more research.

[Helix]

The adapters that morsel point out are good, however i still prefer the LC audio ones because of the 2 decoupling caps on it. If you do get those brown dog ones, there is no reson why you shouldn't solder the caps on top (just a bit fiddly).

The caps are there to smooth and filter the power, as a last ditch effort to try and stop (maybe present) digital hash on the power supply line comming in to the op-amp. They also allow the op-amp to see a very low impedence supply which is useful to keep the bass tought and the trebels smooth especially under heavy loading (for example input on a ZEN amp). The caps are not essential but prefrable.

[Variac]

Hey, I was looking at the LC site and they have the Zapfilter device. It uses discrete componants instead of opamp chips.

I understand that opamps are pretty darned good but it might be a decent idea, especially if you listen to people's opinions about op amp chips on the Pass site

The think that caught my eye was that it can be configured to be a balanced output. Since I use the Pass balanced pre and power amps this would be cool, Balanced outputs on players tend to be available on only the top models.

Now, my ignorance of electronics will be only too clear!!!

I have 2 ideas:

Is there a simple way to make a balanced output module with premium op amp chips? This would be a useful project, and probably not too difficult?

Can you use a pre-amp design such as the Pass balanced line stage to replace the output opamps in a SACD player? (If you keep it right next to the SACD circuitry? Or I suppose you can make a discrete op amp circuit as Mr. Pass describes on his web site to substitute, i.e. make your own zap filter.

These sound like projects that you clever folks could whip out in a trice -or maybe a quint, especialy the chip based balanced. Or has this been discussed to death in a thread I missed?

Thanks, Mark

Still hasn't finished his Son o Zen
(O my God!!, Gromanswe you are contagious )
Actually I like the tagline idea

[morsel]

Helix, the bypass caps are rarely needed and their presence makes the LC Audio modules too big to fit in many applications. Air wiring the caps is a messy kludge, a waste of time, and to really imitate the LC audio module you would need a ground tether from the main pcb ground to the junction of the two caps, which is an even worse kludge.

Bypass caps are generally too small to be power supply reservoirs, so they will do nothing for the bass, treble, or power supply ripple, for that matter. The actual purpose of these caps is to prevent finicky high bandwidth opamps from oscillating under certain circumstances. True fast reservoir caps, such as the 6.8-10µF Wima polyester box caps, are too big to air wire onto the adapter.