NareshBrd,
I am not able to open the linked images. keeps saying "loading" and the image does not open. What is it supposed to be?
I am not able to open the linked images. keeps saying "loading" and the image does not open. What is it supposed to be?
This thread has made me think and I am tempted to recall my 205CIIL from it's holiday in Norway to try it out. I've got a range of MMs from 2mV to 12mV so the MM stage I am curently playing with has gain to incorporate that but I never worried about whether the noise would get too high at max gain. I need to check those sums. There is a neat circuit Hans Polak simulated a couple of years ago as an MM front end for digital interfaces (think focusrite scarlet) which would do the job.
But given we are only talking an extra 6dB in my case I doubt I would need it. But I do like making life difficult for myself for lolz 🙂
But given we are only talking an extra 6dB in my case I doubt I would need it. But I do like making life difficult for myself for lolz 🙂
BTW, I have boards for the “non plus ultra”Phono-Preamp by Hans Polak. The MC version has Gain 60dB@1Khz, The MM version is unspecified gain. The bummer is components have to be changed for MM/MC so no way to switch between.
Hans board is very good. And Hans is active on this forum and would be happy to help you work out which is the best option for your cartridge. If you have those boards I would build them.
Has anyone tried or considered the Cordell VinylTrak Phono?
http://www.cordellaudio.com/preamplifiers/vinyltrak.shtml
http://www.cordellaudio.com/preamplifiers/vinyltrak.shtml
I had chosen the quick reply option, which does not allow attachmebts.
My bad.
Once again, I acknowledge that these are net downloads, not my work.
My bad.
Once again, I acknowledge that these are net downloads, not my work.
At least one person has built that, but no PCBs are available. Scott Wurcer did a very interesting simplified version of this and EUVL was looking at producing some PCBs for that. I haven't chased recently to see if they came to fruition as I'm a couple of years behind on projects.
The damped RIAA Bob uses is a very interesting (if slightly alien to most) concept but I think it could be an interesting leveller for MM users.
I copied the circuit from my Kenwood KX-A36, which uses 5532/6556, and made a pre amp using the TL072.
I used a 12 volt wall wart, and had to change the input and output resistors. The linear wart gave about 17 volts at that low load, good as the output is proportional to supply volts.
A Thorens TD 309 fed a Philips set with 2030 on one channel and 1875 on the other, both were Chinese branded chips.
The listener had Sony speakers in rose wood finish from his college days in the 1970s, and was satisfied.
A ground had to be made, and connected to turn table ground, or noise was a problem.
The AD 797 looks good on the spec sheet, in real life this forum will have experienced users to give their opinion.
I used a 12 volt wall wart, and had to change the input and output resistors. The linear wart gave about 17 volts at that low load, good as the output is proportional to supply volts.
A Thorens TD 309 fed a Philips set with 2030 on one channel and 1875 on the other, both were Chinese branded chips.
The listener had Sony speakers in rose wood finish from his college days in the 1970s, and was satisfied.
A ground had to be made, and connected to turn table ground, or noise was a problem.
The AD 797 looks good on the spec sheet, in real life this forum will have experienced users to give their opinion.
akitika phono
Only MM but this designer claims:
Phono Preamp
"Electronic Termination for Lowest Noise
For minimum noise, the preamp uses an electronic termination scheme. You'll recall that the standard loading resistance is 47 K Ohms. If you do this with a 47 K Ohm resistor, you get significant amounts of noise. Instead, you can terminate with a 1 Meg resistor in a controlled gain Miller loop that makes it look just like 47K Ohms, but it has (ideally) 13 dB less noise. This, along with the rest of the careful design choices makes this an extremely low noise preamplifier. You can read more about the technique here"
https://www.akitika.com/documents/ElectronicCooling.pdf
Does this mean the gain can be increased further without noise issues?
Only MM but this designer claims:
Phono Preamp
"Electronic Termination for Lowest Noise
For minimum noise, the preamp uses an electronic termination scheme. You'll recall that the standard loading resistance is 47 K Ohms. If you do this with a 47 K Ohm resistor, you get significant amounts of noise. Instead, you can terminate with a 1 Meg resistor in a controlled gain Miller loop that makes it look just like 47K Ohms, but it has (ideally) 13 dB less noise. This, along with the rest of the careful design choices makes this an extremely low noise preamplifier. You can read more about the technique here"
https://www.akitika.com/documents/ElectronicCooling.pdf
Does this mean the gain can be increased further without noise issues?
Electronic cooling can reduce the noise a bit with high-inductance cartridges (hundreds of mH), although even then the difference is usually only noticeable in between records and not when there is a record playing. For a low-inductance cartridge like yours (33 mH), the effect is negligible with or without record playing.
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Thanks, for pointing that out!
Then, so far, Cordell's VinylTrak is the design of choice, as linked to it earlier. MM+MC!
Does anyone know of anyone who has pcbs?
Does anyone know of anyone who can design the pcbs?
Does anyone know of anyone, in general?
Then, so far, Cordell's VinylTrak is the design of choice, as linked to it earlier. MM+MC!
Does anyone know of anyone who has pcbs?
Does anyone know of anyone who can design the pcbs?
Does anyone know of anyone, in general?
I have built a phono offered in this forum that is AD797 based. I am shocked at how low noise design it is. It is the quietest phono I have ever heard. I'm sure it's still around I would have to do some searching. Went through about half a dozen phono pres before I settled on this one.
By the way, what Bob Cordell calls synthesized loading is exactly the same as electronic cooling. Its efficacy increases when you use a high-inductance cartridge in damped mode, but again, it's not very relevant in your case.
No one
PM hans Polak, ask him questions build the boards you have and listen. Worry about other designs and option later would be my advice. Trust me on this Been there and got the piles of unfinished projects to show for it 🙂
I already have the boards for Non-plus phono by Hans Polak. I should build those first. This is what Bill referred to, wisely.
Right, I had overlooked post #23. Looking at the schematics in the Linear Audio article about the moving coil version, I think only a few component value updates would be needed to make it perfectly suitable for your cartridge - but Hans knows that better than I do, it's his design.
Hans had already made a provision for an MM version. He provides instructions and values. This is the one I am about to start building. For me, the downside was the inability to have a single phono stage that is switchable between MC and MM. So it would have to be two versions of this built into the same box, with an MM/MC switch. I suppose that would work OK as well, yes?