Sony SACD opamp upgrade with Ad8610 opamps?
I fully admit I am new to DIY at this level, but I was wondering what anyone thinks of replacing the audio board opa2604 opamps in the SONY SCD 777es with the new Analogue Devices AD8610 opamps?
My research suggests that this opamp outperforms the opa627 with the added benefit of a more neutral midrange and speed of the ad825 with deeper bass response.
Any thoughts or suggestions?
I don't have any experience with modifying SACD players, but from what I have read it is possible to bypass many of the stages on the output and to take the signal off at a very early stage. Some have suggested that there are at least 4 stages per channel which can be bypassed! I can't for the life of me remember the site I read this at YESTERDAY... (smacks head and says DUH! ):confused: )
I would like to alter my cheap SACD and hopefully use a discrete FET or tube stage on the output, as well as upgrade the clock and power supplies throughout. Unfortunately, being newer technology, there isn't a whole lot out there yet about what to do, and I'm no digital guru, that's for sure.
Do you really think there would be an audible improvement with just a simple op-amp switch?
Vacuumstate.com is has one
Vacuumstate has an upgrade like that out and will have one out for my SACD player next month.
I just like playing around with the unit and would like ot see how the player sounds with the best opamp line state versus the discrete components line stage.
vacuumstate takes their feed before the DAC using a low pass filter and
LCaudio.com has the zapfister that takes it immediately after the DAC.
I will get the vacuumstate unit when it is available
I really like the new AD8610 op amps, but be careful about plugging them as a direct substitute for any of the op amps you mentioned.
Most op amps run at +/- 15 to 18V supplies. The AD8610 cannot be run over +/-13V. Therefore, you should check the circuitry voltages, or at least study the type and method of regulation, to see if the current op amps are using a +/-12V supply, prior to soldering in the AD8610.
You cannot replace them directly.
Check the pin configuration!
A company called Audiocom-uk.com makes diy upgrades for this player. One of these is a replacement of all the regulators in the system with upgraded superregulators.
Their list is as follows:
Audiocom recommend a change of regulators to their super regulators.
The maximum on any of these regulators is 10v.
I think the existing voltage is ok.
Here are the replacements for the Sony by Audiocom.
IC105 IC - M5F7807L Super-regulator/A601002LDO 8v neg
IC106 IC - M5F7907L Super-regulator/A601009LDO 7v neg
IC205 IC - M5F7807L Super-regulator/A601002LDO 8v neg
IC206 IC - M5F7907L Super-regulator/A601009LDO 7v neg
IC308 IC - M5F7805L Super-regulator/A601000 5v pos
They also recommend replacing the OPA2604s with OPA627s in a separate modification.
LCAudio.com also make an a AD825 module that holds 2 AD825s as a direct replacement for the OPA2604 and the AD712 regulatores. I intend to get a couple of these and with some microsurgery, replace the AD825s with the AD8610ARs
A bit of effort, but this should work
While I am an obvious fan of DIY and have had great success in the past modifying commercial units, one should always keep in mind that engineers are (normally) far from stupid. The 2604 is a VERY good op-amp and would have almost certainly been selected with a particular quality in mind (ie voiced). You may not agree with this quality, in which case, for your ears, you will "improve" the performance by replacing. However in my experience the 2604 has a slightly “warm” quality and may have been chosen to tame an otherwise harsh output.
With regards "extra" stages. Anyone with experience in manufacturing, and particular Japanese manufacturing, will agree that every single component in those “extra” stages will serve a purpose. Whether that purpose applies to you is the question. For example, a favourite circuit to eliminate is the “mute” function on the output. Removing will sometimes produce clicks and pops as the unit switches functions, however some believe there is a performance improvement in removing, and live with the clicks/pops.
I’m not sure I’ve shed any light on your original question, but hope I can encourage you to look at the “big picture” when modifying commercial components by stepping into the engineer’s shoes and trying to ascertain what they were trying to achieve. There are always tradeoffs made between cost and performance, the greater the ratio in favour of cost when designing, the more success you are likely to receive when modifying.
Did you carry on the AD8610 replacements? How did they do? Improvements?
This FET/JFET AD new line sounds interesting, but they all seem to be SOIC. How do you do to replace them on DIP chips?
Finally installed the AD8610s as I/V converters...
As part of my ongoing curiousity, I finally upgraded the I/V opamps in the SCD777es to the New AD8610s.
Thanks to Fmak and all who gave this novice help and advice.
Used the new dual to single SOIC/DIP converter board ($2.59) from Brndg.com
Did not need any bypass caps, Fmak you were right, and it all turned out cheaper than either the LCAudio or Audiocom opamp boards.
The installation was quite a bit of work, but it all went fine.
I have only had the units in for a day so they are still burning in, but what I note immediately is greater midrange presence and much greater clarity of instruments. Complex sections are now more accurately presented.
Notes and transitions now much smoother; as if the dots are now more cleanly connected. At times, with the OPA2604s in place certain tracks had sections that did not play musically especially at crescendos with strings and voice sepecially and I would intuitively brace myself against these parts. I suspect this is some of the cause of listening fatigue. Now to my pleasure and surprise these passages have joined the rest of the musical presentation.
I had intended to compare these to the AD825 and AD826, but I think I am satisfied enough to leave them in. Maybe the pros can compare them.
Besides, I intend to compare this option to the Vacuumstate mod that I will install later.
I do not know how long these opamps will take to break in...does anyone know? I will post an update later.
Other mods installed to date are;
New WBT RCA with signal directly from Audioboard
Audio PS inductor removed
Caps and resistor upgrades per Ruchard Kers's original specs
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