I will try it all, as before, until I get the result. I prepared a PCM56 board for experimentation, it is too expensive to play with AD1862 and especially PCM63.
Could you please explain it?
I had a discussion with one of the technical guy from Sowter, I requested factory measurements of 1945. They did the measurements transfer only, and the frequency response is starting to roll of around 20kHz (40kHz is about -0.5dB)
So I think you’re right about the high frequency loss.
The higher capacitances what you are referring is the cable capacitance after the Transformer, or what kind of capacitance? Are there any way to minimize it, to improve the high frequency transfer?
I have the opposite experience. After Zen Mod sent me this.
The Signetics NE5532 with a line is like voodoo magic and gives me butterflies in my gut.
The Signetics NE5532 without a line sounds the same, but with a bit more muddiness (inaccuracy).
The TI NE5532 version has the most muddiness in the sound. I haven’t yet heard the Philips NE5532 version.
There’s also a military-grade Signetics NE5532 ceramic version with 'FE' at the end. It’s very hard to find, and the question remains whether the ones on eBay are genuine.
The factory TI version on the Fosi V3 is suspect and might be fake, judging by how it sounds.
Anyone making a DAC with the AD1865 should consider Signetics opamps – they’re incredibly precise and perform exceptionally well.
They even sound better than the Muses02.
Who knows, maybe your chakras will reopen! 😎
My experience is with @NIXIE62 transformers rewound from a local craftsman Đole. First it was connected 1:9 and the RIV was on secondary and the sound was better than OPamps. I tried different values for RIV mresistors and the lower the value the better the it sound. Connected the trafo to 1:18 and reduced the RIV to secondary and the sound was better. There is no gain for direct drive amps so I go through tube preamplifier (Kondo M7 clone with ecc82). In the end, when we compared it with a Lampizator DAC, the owner remembered that Sowter said to put 47K on the secondary and 25R on the primary, so we changed it and it was the best PCM63 sound I've heard (pcm63+trafo IV+c3g+AVC to amp). I ended up having to upgrade my Kondo M7 clone, paralleled the Mundorf MCap Supreme output capacitors with the Duelund Alexander and added capacitors to cathode resistors and get more gain.
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It's not the same amplifier, hence the differences. The NE5532 (fake or original, no one knows) sounded much murkier than the OPA1656. I also tried Sparkos SS3602, they were much sharper. That left the OPA1656. Amplifier is Ayima A07, owner @skrstic.
The same combination, PCM1702/OPA1655 sounds too sharp to some, too dark to others, and it sounds optimal to me. It depends on the ears, what is between the ears and the rest of the system, especially the speakers. 😁
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And the speakers are not the same everywhere. On my speakers, OPA1656 sounds too aggressive. I feel some hyperfrequencies in the middle ear that get boring over time.
Those Signetics NE5532 are obsolete, and ebay is full of fakes. Similar to the Phillips version which is also excellent, as some say. You need to find the original, let's say like M got it from Z. And these newer productions don't seem to be at that level. I have the original 30-year-old TI models, they are cloudy to me.
OPA 2604 always sounded better to me than NE5532 in line preamps, in CD players and the like. It is not for the Phono stage, there is a better to keep NE5532, because it is less noisy.
Now what if I give @mikorist original BB OPA2604 and it is better than Signetics NE5532? 😁
OPA 2604 always sounded better to me than NE5532 in line preamps, in CD players and the like. It is not for the Phono stage, there is a better to keep NE5532, because it is less noisy.
Now what if I give @mikorist original BB OPA2604 and it is better than Signetics NE5532? 😁
You can give it to me. I won't refuse. But I doubt that any OPAMP can beat them in terms of warmth. You must give me tubes to beat them!
I don't believe you. Well, man, even those tubes I heard at your place sound harsh.🤣
Lol,
And no one are trying AD8567 that sounds better than AD797, or AD9631, or OP828...
In the middle age I liked JRC4580DD... in a Giordano Bruno spirit. Still great little can to buff a a bigger can (headphone)
Of course must be tested with WJ super regs to understand if the sounds difference beats the AD811, lol... (at least on the thermal noise, should be beated easily... w/o cryo cooling kriptonit made).
I do it 20 y ago in Philips/marantz cd players to I/V with the op2604 : nice sound (the Jfet input ?) but what a flabby mid bass to bass, I could not live with it but for relaxed session for dinner after a hard working day.
I still have some op2604 blessed with saint oil as backup if the wind turns of direction at the stock exchanges !
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