I twisted myself a bit in post 179 -- it turns out that if the Pearl3 is "hot", i.e. rising output relative to the RIAA curve, the devil may be in the compensation for the first operational amplifier which is 4.7pF. You can just stack another capacitor on top of the 4.7pF to tame the response. Elsewise, should look as Wayne has shown.
I am sorry, C2 is the compensation capacitor around the first operational amplifier. YMMV For purposes of simulation I optimized it for 0dB at 1kHz. In real life 4.7pF. C0G usually but in ham-radio land, as Wayne suggested, just twist a few inches of wire to attain the correct value.
Here is how changing C4 affects the compliance to the RIAA curve for t3, again it's just a simulation.
Here is how changing C4 affects the compliance to the RIAA curve for t3, again it's just a simulation.
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It is an interesting process to start looking for a turntable to get "permission" for P3 build.
There are so many models and so many price-ranges and reviews etc. etc.
I think I will add a requirement that it should be nice to look at also.
If 2SK170 is still the most silent (over the SK209) an octet could be nice even that it is not a requirement.
Mitchell Gyrodec looks nice and also Technics 1200G. Two very different TT's. 1200G reminds me about the "old days".
There are so many models and so many price-ranges and reviews etc. etc.
I think I will add a requirement that it should be nice to look at also.
If 2SK170 is still the most silent (over the SK209) an octet could be nice even that it is not a requirement.
Mitchell Gyrodec looks nice and also Technics 1200G. Two very different TT's. 1200G reminds me about the "old days".
I have now got the official "permission" for a P3 build!
I accepted a "pre-black-Friday" offer:
Instead of the kit-included Audio Technica cartridge I get it with Ortofon 2M Black LVB 250 .....the speciel Ludvig Van Beethoven anniversary model.
I hope this TT in combination with a P3 can play some nice music. Interesting also to compare digital with Vinyl so I can judge for myself if a digital recording pressed on vinyl can sound better than the raw digital file via a decent DAC. The seller of course claimed that......
It is a German TT! ....and Danish cartridge!
I accepted a "pre-black-Friday" offer:
Instead of the kit-included Audio Technica cartridge I get it with Ortofon 2M Black LVB 250 .....the speciel Ludvig Van Beethoven anniversary model.
I hope this TT in combination with a P3 can play some nice music. Interesting also to compare digital with Vinyl so I can judge for myself if a digital recording pressed on vinyl can sound better than the raw digital file via a decent DAC. The seller of course claimed that......
It is a German TT! ....and Danish cartridge!
The multiple JFET input got me to thinking about the Toshiba 2SK2145, which can readily be purchased. It happens to be a dual, touted as low noise. In a 5 pin SOT package with common source. This application requires separate sources, common drain. Most JFETs are symmetrical in that you can swap source and drain connections. So I wired it up that way using the same topology as Pearl3 with 10 ohm resistors in series with each "source" and to a common 10 ohm resistor. I happened to choose the BL version of the 2SK2145 spec'ed for a 6 to 14 mA IDSS. What I found was that the two devices within the package are very closely matched as you would expect. I also found that other parts from the same batch were also quite close to each other. All four devices had a drain current of between 4 and 4.1mA in this circuit.
Hmm.... Jim didn't notice it's a belt driven table..... Bravo!
Now for the necessary upgrades! Plan on a better power supply! Something robust that can see you through the IV movement of the 9th... when the guy blasts out "O Freunde"... Hey! You got the LVB cartridge... No Mozart For You, Forget Rossini!
( BTW, what are the LVB upgrades all about? Oh.. " Nude Shibata diamond on a Boron cantilever" ). DON'T DROP IT!!!!
So, now you'll have your TT. A brand new one... hmm... how about... records? cleaning supplies?
A good 24/96 recording over a good DAC ( no need for megabucks ) will match the record. (*) What is truly important is to have LOW NOISE in the analog chain. The P3, if anything like the P2, is very quiet so it's extremely important to have a quiet front end.
I wonder if they will release an upgraded bearing for that table.
Get ready to REALLY SPEND MONEY now..
(*) My current set up is an Android Tablet running USB OTG to a Burson Swing with the V6 Classic opamps. Mostly Tidal HiFi and my own recordings in the NAS. I should start looking for a Cadenza Black one of these days... see if I can get a good price from Dan.
NOTE: Will a Cadenza Black at 0.33 mV drive the P3 OK?
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Yes, the LVB should be a bit "faster" than the standard 2M black.
I guess it is one of the best MM cartridges.
I still need all the cleaning stuff.
I gave away all my Led Zeppelin, Beatles, Doors etc. LPs many years ago. But then i have the chance to get new ones without any "noise".
I have no idea how to get the best pressings. I can see the vinyl shops write the weight of the vinyls so I guess the heavy ones are better quality but I need learn all about this later.
I still need all the cleaning stuff.
I gave away all my Led Zeppelin, Beatles, Doors etc. LPs many years ago. But then I have the chance to get new ones without any "noise".
I learned it is possible to get records that are so silent that you can do A/B tests between DAC / Vinyl where the vinyl does not reveal itself with the usual "noises" linked to vinyl.
I have no idea how to get the best pressings. I can see the vinyl shops write the weight of the vinyls so I guess the heavy ones are better quality but I need learn all about this later.
I will listen to the TT "as is" and hope it does a good job without any updates
......it is German!
Why are most LP's not 100% centeret? .....I can see cartridge going a bit from side to side all most Youtube videos demonstrating TT's. Then all the effort made by the TT manufactures.....almost waste of time.....I will check that before I pay for a LP!
I guess it is one of the best MM cartridges.
I still need all the cleaning stuff.
I gave away all my Led Zeppelin, Beatles, Doors etc. LPs many years ago. But then i have the chance to get new ones without any "noise".
I have no idea how to get the best pressings. I can see the vinyl shops write the weight of the vinyls so I guess the heavy ones are better quality but I need learn all about this later.
Yes, the LVB should be a bit "faster" than the standard 2M black.
I still need all the cleaning stuff.
I gave away all my Led Zeppelin, Beatles, Doors etc. LPs many years ago. But then I have the chance to get new ones without any "noise".
I learned it is possible to get records that are so silent that you can do A/B tests between DAC / Vinyl where the vinyl does not reveal itself with the usual "noises" linked to vinyl.
I have no idea how to get the best pressings. I can see the vinyl shops write the weight of the vinyls so I guess the heavy ones are better quality but I need learn all about this later.
I will listen to the TT "as is" and hope it does a good job without any updates
......it is German! Why are most LP's not 100% centeret? .....I can see cartridge going a bit from side to side all most Youtube videos demonstrating TT's. Then all the effort made by the TT manufactures.....almost waste of time.....I will check that before I pay for a LP!
