This is what it is all about. IF we could just use IC's, and get the same sound 'quality' we would. But IC's, almost invariably, use class B output stages, high open loop gain, and low open loop bandwidth, for starters. It changes the sound 'quality'.
jacco vermeulen said:
Not anytime soon, unfortunately. Beyond finishing the YAP construction (and the web site) I'm busy designing the layout for a RIAA preamp (with OPA827 and OPA211, to the horror of the discrete fanatics, the prototype beats hands down a pair of input 2SK170 in noise performance, except for very low frequencies). I have a bunch of old vinyls and I decided to get a turntable: a VPI HW-19 MK3 with the MK4 bearing and platter upgrade, an Audioquest PT-9 tonearm and a Benz Micro Silver cartridge. Sounds very good, but this needs a good preamp ASAP and I'm not crazy enough to pay a couple of thousands for a good commercial unit. What I've seen at affordable prices is very poor. I believe in very good opamps, not in a 5532 in a small metal case.
Otherwise, it is really amusing to see how people who claim to hear wires directionality are easily accepting preamps built in bipolar and FET technologies to sound the same.
syn08 said:
Since the OPA827 specs at 4nV this will need some explaining??? If you JUST want to talk about noise optimized discrete will always win. .4nV is doable for MC without being too exotic. .12nV could be done with some extreme measures.
scott wurcer said:
Well, you are right about the intrinsic device. But then I refuse to use in the input stage something raw like a common source stage with virtually no significant PSRR. A simple regulated power supply (which I did) adds enough noise to such a stage to make it a poor choice comparing to the OPA827. Of course, something like a Jung regulator (or perhaps batteries, although I'm not so sure about) will make the 2SK170 a clear winner, but i'm not sure I would go for that level of complexity? And adding PSRR to a 2SK170 input stage adds noise as well, or at least I was not able to find a way around. Any ideas how to combine the 2SK170 better noise performance with a decent PSRR?
PMA;
Thank you for sharing the interesting listening comparison 😉
It tells me that I (and others) have been right about what really makes a big difference, and what's not. To me this result shows that you get very a long way using common sense, good components (BTJs/Fets/Caps etc.) and good layout.
I have always been able to tell a discrete design from a opamp based one, but has always only noticed very small "maybe" differences between two similar diskrete design with same topologi 😉
This clearly shows that you CAN make a audiophile preamp (like PMAs DisPre II which is my main preamp at this moment) at small costs.
Congratulation, Pavel 😉
Thank you for sharing the interesting listening comparison 😉
It tells me that I (and others) have been right about what really makes a big difference, and what's not. To me this result shows that you get very a long way using common sense, good components (BTJs/Fets/Caps etc.) and good layout.
I have always been able to tell a discrete design from a opamp based one, but has always only noticed very small "maybe" differences between two similar diskrete design with same topologi 😉
This clearly shows that you CAN make a audiophile preamp (like PMAs DisPre II which is my main preamp at this moment) at small costs.
Congratulation, Pavel 😉
Syn08, IF you don't want to bother with details, such as a quiet power supply, then please stick with IC's. You remind me of someone who refuses to put quality tires on a sports car. Stick with a Toyota sedan, in that case, and leave the Porsche alone.
Of course, we could make an active load, just like IC manufacturers do, but I personally prefer to make quiet power supplies, instead. It is one step further removed from the audio itself, than an active load, and doesn't tend to amplifiy its own noise.
Of course, we could make an active load, just like IC manufacturers do, but I personally prefer to make quiet power supplies, instead. It is one step further removed from the audio itself, than an active load, and doesn't tend to amplifiy its own noise.
Pavel, no offense, but this is not really a detailed description of how listening comparison did take place, what other components/cables were used and is of course heavily biased isn't it?
As John has already said, power supply is a very important part of the preamplifier. I would also add importance of signal wiring (extremely short in my case, and made from very low capacitance cable).
Hats off to JC-2 housing. If I used so many inputs and switch options, I would also need similar box with wall separated spaces for PSU etc. Only for the reason I have 1 input, no switches and output directly from PCB, I can use a simple box.
Hats off to JC-2 housing. If I used so many inputs and switch options, I would also need similar box with wall separated spaces for PSU etc. Only for the reason I have 1 input, no switches and output directly from PCB, I can use a simple box.
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PMA, I should think that worrying about the rest of your set-up by others is not helpful. Usually, we all learn to live with our existing sound system and listen through its limitations, IF it is reasonably high quality throughout. Changing just one component such as a preamp will show enough difference to be audible, and that is what is important. You are, in fact, comparing two preamps designed with the same intentions and design rules. This makes them sound nearly the same, yet there will be differences.
Some here will attack you, insisting that no differences could really exist, others will dilute the test with concerns over blind vs non-blind, supporting component quality or type, etc. But your approach to this test is the same as all hi end designers do, and we make progress.
Some here will attack you, insisting that no differences could really exist, others will dilute the test with concerns over blind vs non-blind, supporting component quality or type, etc. But your approach to this test is the same as all hi end designers do, and we make progress.
PMA - good work!
When I find that two piece of equipment sound too similar, I start to suspect that there are limitations to my stereo system. Not sure this is so for your setup, though. I also like to focus on sonical items that are not similar.
Looking at the used components, I am convinced that you can get
even higher sonical qualities by using other components.
Easiest is to use another pot. Then change all the resistors.
It is all in the details.
Sigurd
When I find that two piece of equipment sound too similar, I start to suspect that there are limitations to my stereo system. Not sure this is so for your setup, though. I also like to focus on sonical items that are not similar.
Looking at the used components, I am convinced that you can get
even higher sonical qualities by using other components.
Easiest is to use another pot. Then change all the resistors.
It is all in the details.
Sigurd
PMA said:
Syn08 -
a well designed OPamp based line or RIAA amp can sound good, even very good. No doubt about that. I listened to a 5000Euro RIAA amp from Karan last week. We used a Lyra Skala cartridge.
Sonics were very good. Maybe not that as good as a Bonnec in the highs but for being an OPamp based RIAA it sounded darn good! The Karan looked as it was very well implemented.
http://www.vinylbutiken.com/
I got so intrigued, that I have started my own RIAA design. For MC cartridges only, and I plan to use some form of diskcrete input low noise stage. I do not worry about PSRR.
Do you have a link to your RIAA design?
Sigurd
a well designed OPamp based line or RIAA amp can sound good, even very good. No doubt about that. I listened to a 5000Euro RIAA amp from Karan last week. We used a Lyra Skala cartridge.
Sonics were very good. Maybe not that as good as a Bonnec in the highs but for being an OPamp based RIAA it sounded darn good! The Karan looked as it was very well implemented.
http://www.vinylbutiken.com/
I got so intrigued, that I have started my own RIAA design. For MC cartridges only, and I plan to use some form of diskcrete input low noise stage. I do not worry about PSRR.
Do you have a link to your RIAA design?
Sigurd
syn08 said:
courage said:
Franklin, no problem.
CD: LINDEMANN CD1 SE
Link Cable: Andrew Heliax + WBT connectors, 50cm
Preamps: Parasound Halo JC-2, Macura Instruments Dispre II
XLR link cable: NEOTECH NEI-1002 silver, 50cm
Power Amplifier: Parasound Halo A21
Speakers: Nobble Audio Lucid (bass ScanSpeak as in W.A. Sophia, middle and high Thiel & Partner as in Avalon, Mundorf coils and capacitors)
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Sigurd Ruschkow said:
First, not my system in this case. Second, other preamps do not sound similar in this setup.
john curl said:
John, thanks for the comments. I do not care that much what some people would say 😉 . I know well what I have heard, and it is the most important observation to me. I also now the degree of "similarity" I have heard, and as you are saying: "yet there will be differences".
Thanks for the comments to the others as well, if positive or negative 😉
Sigurd Ruschkow said:
Wow, some really expensive stuff your are dealing with...
You'd better worry about the PSRR if you really care about noise and overall performance.
The RIAA project is in the early stages. I usually don't publish designs until they are not finished and tested, so for the moment here's the OA input stage. It may change significantly during the project lifecycle.
Sorry for the OT
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