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Old 20th October 2013, 08:37 PM   #681
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Are these two from Denonīs professional line? Not sure what that really is? They were the top of the line back some time ago. There is known problems with the transport/lasers. I bought them thinking I would use them as dacs. I was luck that the both ended up being repairable. The 5000 is a two channel audio dvd player, the 9000 is 5.1 with all channels using PCM1704s. Nicely built with a few peculiarity, like the 5000 has no decoupling caps on the digital side of the dacs. Designed to be there but left off when built(?).
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Old 20th October 2013, 08:43 PM   #682
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I should correct that last bit. They didn't install the ceramic decoupling caps. They only have silmic caps for that duty. There are places to install the ceramics for high freq decoupling, Denon just left them out.
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Old 15th November 2013, 02:49 AM   #683
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Talking AD844 triple stack + BUF03

Hi George, Finally wired up the BUF03's off the TZ point of my triple stack (SOIC) I/V's. While I was waiting I switched to Cinemag transformers for the filter function instead of the Edcors. With the triple stack and running the bottom 844's output stage and the Cinemags, I was really quite happy. However I am listening to the BUF03's output and I must say this isn't a subtle change in my system. I am listening to a remastered CD set, Pink Floyd "The Wall". Dynamics are outstanding, clarity and detail. Bass is super. I will work on my Pedja discrete circuit next week. I am short a few Wima bypasses. I will report my experience using the BUF03's as a buffer. Dave
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Old 16th November 2013, 08:57 AM   #684
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Quote:
Originally Posted by Torchwood421 View Post
Hi George, Finally wired up the BUF03's off the TZ point of my triple stack (SOIC) I/V's. While I was waiting I switched to Cinemag transformers for the filter function instead of the Edcors. With the triple stack and running the bottom 844's output stage and the Cinemags, I was really quite happy. However I am listening to the BUF03's output and I must say this isn't a subtle change in my system. I am listening to a remastered CD set, Pink Floyd "The Wall". Dynamics are outstanding, clarity and detail. Bass is super. I will work on my Pedja discrete circuit next week. I am short a few Wima bypasses. I will report my experience using the BUF03's as a buffer. Dave
Yes Dave for such an old (very old buffer) the BUF03 is a stunner, and they are high biased and will burn your fingers even with a heat sink (and before anyone say it. No they're not occilating) +- 16vdc is the highest I would go.

BTW yesterday we finally had the A/B with 2 identical cdp's with PCM1704k's in them between my 2 stack and my friends 4 stack intedical cdp's both using the BUF03 as output buffer. The system to remind all was Wilson Watt Puppy 8's Halcro DM68's (100kohm input impedance) and my Lightspeed Attenuator as the passive pre.

Both were very very good but a touch different. 2 of us had the 2 stack winner by a hair and the other listener could'nt decide.
The 4 stack was a touch less delinated in the bottom end and a bit heavier/weightier, the 2 stack sounded like it went lower.
The 4 stack also did not have quite the jump factor that the 2 stack had in dynamics.
Two of us thought the 4 stack was just a very little grainy on female voice but that could have been the recording, yet we think we didn't hear it on the two stack.

So there you go with the PCM1704 dac with low -+1.2mA output.
1 x AD844 is very good, far better than any negative feedback opamp i/v
2 x AD844's stacked blows away a single big time
3 x stack (shrug of the shoulders)
4 x stack (shrug of the shoulders again)

Cheers George
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Old 16th November 2013, 11:25 AM   #685
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Quote:
Originally Posted by georgehifi View Post
Yes Dave for such an old (very old buffer) the BUF03 is a stunner, and they are high biased and will burn your fingers even with a heat sink (and before anyone say it. No they're not occilating) +- 16vdc is the highest I would go.

BTW yesterday we finally had the A/B with 2 identical cdp's with PCM1704k's in them between my 2 stack and my friends 4 stack intedical cdp's both using the BUF03 as output buffer. The system to remind all was Wilson Watt Puppy 8's Halcro DM68's (100kohm input impedance) and my Lightspeed Attenuator as the passive pre.

Both were very very good but a touch different. 2 of us had the 2 stack winner by a hair and the other listener could'nt decide.
The 4 stack was a touch less delinated in the bottom end and a bit heavier/weightier, the 2 stack sounded like it went lower.
The 4 stack also did not have quite the jump factor that the 2 stack had in dynamics.
Two of us thought the 4 stack was just a very little grainy on female voice but that could have been the recording, yet we think we didn't hear it on the two stack.

So there you go with the PCM1704 dac with low -+1.2mA output.
1 x AD844 is very good, far better than any negative feedback opamp i/v
2 x AD844's stacked blows away a single big time
3 x stack (shrug of the shoulders)
4 x stack (shrug of the shoulders again)

Cheers George
Hi George, For the TDA1541A I like the triple stack. It also gets the I/V input resistance down to about 16.7 Ohms which is close to the "ideal" 12 Ohms. I was also surprised by the holographic sound field. I have several more hours listening time now. I am a happy listener. Thanks for the information on the PCM1704's. I am considering building a dac based around that chip. Dave
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Old 3rd December 2013, 01:10 AM   #686
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I always wondered why nobody who bought to my place a dsd or sacd front end ever got it to sound as good as my current Redbook setup PCM1704K with the 2 x stacked AD844 I/V stage into the BUF03 buffer.
I guess Daniel Weiss of Weiss dacs with this white paper thinks the same.

Mono and Stereo High-End Audio Magazine: Daniel Weiss White paper on DSD

Cheers George
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Old 3rd December 2013, 01:19 AM   #687
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DSD as a format is technically broken, that's probably why. This is not a matter of opinion, rather hard math.
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Old 3rd December 2013, 02:00 AM   #688
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Quote:
Originally Posted by georgehifi View Post
I always wondered why nobody who bought to my place a dsd or sacd front end ever got it to sound as good as my current Redbook setup PCM1704K with the 2 x stacked AD844 I/V stage into the BUF03 buffer.
I guess Daniel Weiss of Weiss dacs with this white paper thinks the same.

Mono and Stereo High-End Audio Magazine: Daniel Weiss White paper on DSD

Cheers George
George
Im not silly enough to ever say anything is "better" , because its impossible to convince anyone that your perceptions are "better" than anothers, however
you might be pleasantly surprised at the sound of a I2S driven Sabre with an OP861 I/V , same concept as yours but an even "better" device than the AD844 , PCM or DSD, but then again you might not.
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Old 3rd December 2013, 02:21 AM   #689
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Hi Mick, yes I've got a couple of those 861's here waiting for me to do something with them, even have the second BUF03 for the buffer. I aggree they could be even better than the AD844's it just that it's sounding soooo good at the moment, I'm not rushed.
I even have a second identical 1704 cdp now to do it on, also I have a pair of OPA660, which may even be better.
One day I'll get around to it but for now I'm in heaven listening to to what I have.

Cheers George
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Old 8th January 2014, 03:25 PM   #690
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has this been compared to cen/sen? i'm about to start my 1541 build and the latter methods are on the top of my list because of the cost.
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