Hi everyone,
I recently purchased a Yamaha CD-1330 CD player which is very similar to CD-S700 (same Analog PCB, only two capacitors difference).
I have service manual of both players so I can compare.... I want to upgrade stock OpAmp... say a single OP275 just after DSD1791 DAC.
There is no other opamp till output. So OP275 does differential amp and lpf.
I tend to think about AD826 and AD823 ?
I would like a no-brainer solution as the stock OP275 is already a fine opamp and I already plan some capacitor replacement around it.
Has anyone any advice regarding this matter ? Thank you.
I recently purchased a Yamaha CD-1330 CD player which is very similar to CD-S700 (same Analog PCB, only two capacitors difference).
I have service manual of both players so I can compare.... I want to upgrade stock OpAmp... say a single OP275 just after DSD1791 DAC.
There is no other opamp till output. So OP275 does differential amp and lpf.
I tend to think about AD826 and AD823 ?
I would like a no-brainer solution as the stock OP275 is already a fine opamp and I already plan some capacitor replacement around it.
Has anyone any advice regarding this matter ? Thank you.
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Nice on paper
... I didn't thought of that one... how is it (sound-like) compared to AD826 or AD8066 ?Mine is a CD-1330... everything is same as CD-S700 except one or two things, including Transport
. Tricky Yamaha guys !! Mine had got low quality caps instead of nice FW and Fine Gold. Started changing them so I wonder if I can also swap op275 for a better opamp...I've read part of the "Opamp thread" on other forum and about LT1355 little is mentioned.
Slew Rate is very impressive but regarding sound-quality ? Will it really be better than stock OP275 ?
And circuit-wise ? I have much respect for abraxalito regarding some SD-player information but could anyone help me further or confirm ?
Here's a quick pic regarding implementation.
I was thinking like staying with some AD chip in it... well, starting going "out" can I ask if opa1642 would do any good ? (I know curiosity killed the cat but...)
Anyway, thank you very much for your input !
Slew Rate is very impressive but regarding sound-quality ? Will it really be better than stock OP275 ?
And circuit-wise ? I have much respect for abraxalito regarding some SD-player information but could anyone help me further or confirm ?
Here's a quick pic regarding implementation.
I was thinking like staying with some AD chip in it... well, starting going "out" can I ask if opa1642 would do any good ? (I know curiosity killed the cat but...)
Anyway, thank you very much for your input
!Attachments
I think your just going to have to shortlist a few and try them. An outsider for you would be the OPA2604, probably the most "coloured" sounding of any. Those muting transistors look as though they could usefully be swapped out for small FET's.
Enjoy
Indeed.
Thanks Mooly, I was thinking adding this one too
.
Hello,
It looks like the 3rd order filter in this CDP is inverting absolute phase (if that matters for you). It has the cut-off at 103kHz and puts out 2.2Vrms@0dB (which may give it some advantage in non-level matched comparisons with other players). I have not figured yet what type it is (Butterworth, Bessel etc) and IMHO this may play a bigger role in sound than rolling the op-amps.
If I may suggest the OPA1662 (higher GBW, lower noise and more linear in presence of leaky clocks from the DAC).
It looks like the 3rd order filter in this CDP is inverting absolute phase (if that matters for you). It has the cut-off at 103kHz and puts out 2.2Vrms@0dB (which may give it some advantage in non-level matched comparisons with other players). I have not figured yet what type it is (Butterworth, Bessel etc) and IMHO this may play a bigger role in sound than rolling the op-amps.
If I may suggest the OPA1662 (higher GBW, lower noise and more linear in presence of leaky clocks from the DAC).
Hi sidiy,
if you check the DSD1791 datasheet ? they suggest something interesting regarding this. Only values may differ with those of this CDP.
I am going investigate further upon similar DSD chips in the TI database.
To tell the truth I haven't listened to it. I chose it because for DAC duty opamps need a front-end which is linear at HF, and the usual undegenerated LTPs are particularly poor in this respect. Hence I selected one which avoids the LTP. LM6172 is similar in architecture and sounds very good to my ears in an AD1955 DAC I modded. I didn't suggest this because its bandwidth is such that its a little harder to get stable - the LT1355 is more domesticated.
I haven't listened to AD826 but I do have experience with AD8065 which is the single version of the AD8066. Sounds peculiarly coloured at the top end to me. However this wasn't in a DAC, rather as an integrated amp's input stage.
After long readings, I found DSD1791 should be likely a more or less PCM1793 : design after it is more or less the same in any application so there is plenty written out there. Original design datasheet says NE5532 or OP2134 should be fine... imho, OP275 should better these two given its specs... I think I'll try OPA1662 as suggested and something discrete...
You're luckier than most... I do have OP275GSR in mine.
I did not pay attention to that on service manual... there's big difference in some capacitors aswell. I am glad you gave me info
I think your just going to have to shortlist a few and try them. An outsider for you would be the OPA2604, probably the most "coloured" sounding of any. Those muting transistors look as though they could usefully be swapped out for small FET's.
Enjoy
The muting transistors only mute so there will be no improvement there.
The Op Amp replacement will not produce much if any improvement as the Op Amp was chosen in the factory. The noise level is excellent unless it is faulty in which case as a retired authorized Yamaha Agent we were advised to fit a low noise 4558. Yamaha supplied a 6558 as they have JFet inputs and are very low noise.
Who listens to a CD player with no CD playing? That is what the muting stage is for.
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Many do seem to claim sonic improvements when this type of muting is removed, but the other very real issue is that they can be a source of trouble if the transistors play up which is surprisingly common in this type of bjt application. For some resaon they fail leaky in this configuration (grounded collector and high negative voltage on the base) which presents a weird non linear load to the opamp so distorting the audio.
The perceived problem with muting transistors is that they remain in circuit when not muting.
IMO the rest of the circuit would have to be exceedingly good for replacement to be a worthwhile modification.
edit...unless they're faulty...good point Mooly
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Ok, so first I am going to recap the whole analog board with some Nichicon FG except C53 and C56 of service manual where I will put "something else". I am also going to bypass these with some metalized poly (C54 and C55).
The whole thing came with standard capacitors (Nichicon VR and United Chemi-con SMG).
Next will be replacement of capacitors in power sections with some Panasonic FC.
Last will be Opamp replacement : I think I will start with LME49723MA.
I thank you all for your suggestions
The whole thing came with standard capacitors (Nichicon VR and United Chemi-con SMG).
Next will be replacement of capacitors in power sections with some Panasonic FC.
Last will be Opamp replacement : I think I will start with LME49723MA
.I thank you all for your suggestions
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