So here we are. Q3:
Vc 7; 6.9
Vb 5.4; 5.4
Ve 4.7; 4.8
These are perfect. You're rolling. Now go and listen again.
Pierre
You must be joking! There's nothing to regret. We live and learn and I've learned a lot from you.
Oups, I'm terribly sorry ! I let out the wrong correction accidentally.
Luckily Pierre is here to correct my mistakes
Tomas please report voltages after mods (my repair mistake, sorry, I really apologise) and Pierre's right correction
Best,
nAr
I'm here because I saw your post. Thanks for posting !
Cheers - Pierre
test
Not being selfish, I thought, I could offer you, guys, a glimpse on the difference (or the lack of it?) between my two phono stages? Here is some excerpts recorded especialy for you. (109MB)
http://wtrns.fr/16Lz7Qc4o_QeGM
I would love to read your opinions. My own is: "it could be better". Duh!
You can also try and guess which is which stage, if possible.
It was recorded swapping stages and polarities on the cartridge, via not yet boxed dcb1 to my old mac which doesn't have a battery anymore, so I had to use noisy PSU. A bit crappy, but still good enough to carry out a judgement?
Not being selfish, I thought, I could offer you, guys, a glimpse on the difference (or the lack of it?) between my two phono stages? Here is some excerpts recorded especialy for you. (109MB)
http://wtrns.fr/16Lz7Qc4o_QeGM
I would love to read your opinions. My own is: "it could be better". Duh!
You can also try and guess which is which stage, if possible.
It was recorded swapping stages and polarities on the cartridge, via not yet boxed dcb1 to my old mac which doesn't have a battery anymore, so I had to use noisy PSU. A bit crappy, but still good enough to carry out a judgement?
There is indeed a difference between the 2 versions. But most qualities out of the 2 examples are lost in conversion ... you know standard 44,1 isn't up to par with originals.
Plus, it depends which conversion card you use, external maybe ?
For me both records play fine ... TT is the Planar 3 I guess, don't remember which cartridge you have mounted on.
I would perhaps slightly prefer the 2nd versions of the test samples (assuming it is still always same phono stage order), seems to have a more direct and natural sound. I would find also the sense of space a little better. Oh well, I could be wrong after all.
You should build some other shunts to get double mono PSU on Pearl !!! It would be a tiny/but major upgrade I guess
Best,
nAr
Plus, it depends which conversion card you use, external maybe ?
For me both records play fine ... TT is the Planar 3 I guess, don't remember which cartridge you have mounted on.
I would perhaps slightly prefer the 2nd versions of the test samples (assuming it is still always same phono stage order), seems to have a more direct and natural sound. I would find also the sense of space a little better. Oh well, I could be wrong after all.
You should build some other shunts to get double mono PSU on Pearl !!! It would be a tiny/but major upgrade I guess
Best,
nAr
Anaël, that's close to my thoughts. "Tightness" and spatial info is better on the 2nd stage. It has also a bit more gain, it seems. I've tried to level it when recording, though. Turntable is Planar 3 with a RB300 modded arm. My cartridge is Goldring 1012GX.
Double mono PSU of course would be an upgrade. Not sure if major, though. I can only guess, I would be better off with upgrading TT and cartridge. Planar 3 has a lousy coupling between motor and plinth. I would love to dismount the motor off the plinth onto some solid base and add a Geddon PSU to it. A cartridge change would benefit too. My current one was bought used on ebay. Some german gentleman sworn he used it less than 100h correctly mounted. As it was my first cartridge, I can't really judge.
As a second option, I think of ditching Rega and switching to something more decent. But that's a different $$$ story.
Back to PEARL II, I'm thinking weather some more precise R matching, different caps or getting closer voltage values to Wayne's would benefit? In other words, is there's anything left to tune? Or perhaps it's too silly, as my current rig wouldn't be able to carry out the differences.
Double mono PSU of course would be an upgrade. Not sure if major, though. I can only guess, I would be better off with upgrading TT and cartridge. Planar 3 has a lousy coupling between motor and plinth. I would love to dismount the motor off the plinth onto some solid base and add a Geddon PSU to it. A cartridge change would benefit too. My current one was bought used on ebay. Some german gentleman sworn he used it less than 100h correctly mounted. As it was my first cartridge, I can't really judge.
As a second option, I think of ditching Rega and switching to something more decent. But that's a different $$$ story.
Back to PEARL II, I'm thinking weather some more precise R matching, different caps or getting closer voltage values to Wayne's would benefit? In other words, is there's anything left to tune? Or perhaps it's too silly, as my current rig wouldn't be able to carry out the differences.
I didn't want to spoil the audiotion yet... First is Graham Slee Revelation, second is Pearl II.
Second is Pearl II with Salas Shunt Reg PSU
Not sure if major, though. I can only guess, I would be better off with upgrading TT and cartridge. Planar 3 has a lousy coupling between motor and plinth. I would love to dismount the motor off the plinth onto some solid base and add a Geddon PSU to it. A cartridge change would benefit too. My current one was bought used on ebay. Some german gentleman sworn he used it less than 100h correctly mounted. As it was my first cartridge, I can't really judge.
You're right about Rega setup. It's good but you can find even better. The major upgrade to Regas is to change the cart for something better. Your cart seems fine, but mind the VTA of the RB 300 might need to be re-adjusted. Rega carts are not very high and higher cartridges need the arm to be set up "higher" on the plinth to have the right cutting angle intended. Extra accessory is needed.
More even careful you must be installing the cart on the arm finding for the "right" position. Please do use Vacuum State free protractor. It can take 2 hours mounting !!! and weeks of patient fine tuning to be well set.
Back to PEARL II, I'm thinking weather some more precise R matching, different caps or getting closer voltage values to Wayne's would benefit? In other words, is there's anything left to tune? Or perhaps it's too silly, as my current rig wouldn't be able to carry out the differences.
Let us hear Wayne about that
Best,
Anaël
Second is Pearl II with Salas Shunt Reg PSU
That goes without saying! I'm not building anything without it hehe
VTA spacers are there to be tested. But then again, every record is different and you can't adjust every time accordingly. I've tried Guru protractor, which I couldn't get right. Maybe it really takes too much patience?
Joining you for waiting Wayne to chime in.
I think that the wav files that end with 2 are easily more dynamic and defined.
Youpeeee
Thanks for listening, Salas. Stage 1 will go for sale which will hopefuly fund my new cartridge.
My bro has P3, mounted a Denon DL 110 on it in replacement of the old Elys cart. It took 2 hours to find roughly the guru points. But once break in is done, what a difference !
Best,
nAr
Hi all,
I presume the total gain for the given circuitry is 55db. What do I need to change to reduce the gain to 40db total gain. This is because I intend to use permanently install a MC SUT which will have about 30db gain. About 70db is ideal for my requirement.
You need to lower R16. To what exact value, it remains a mystery to me and, again, maybe Wayne could help us here. I was aiming for 40 dB too and installed 47K instead of 100K. This resulted in a bit more than 42.5 dB, which I can tell by comparing to my previous stage.
You need to lower R16. To what exact value, it remains a mystery to me and, again, maybe Wayne could help us here. I was aiming for 40 dB too and installed 47K instead of 100K. This resulted in a bit more than 42.5 dB, which I can tell by comparing to my previous stage.
Gain figure of 1st stage is roughly 35dB gain
Losses in passive RIAA about 20 dB
2nd Stage gain as per schematic is (R16+R14)/R14 as non inverting opamp
Per schematic x 101 times so, about 40 dB
Total Pearl gain by default 55 dB
To get 40 dB total gain for Pearl II you need to reduce 2nd stage gain to 25 dB or so (= increase feedback !!!)
R16 can be lowered, but you change Cx adjustment too I guess
Passing R16 to 20k gives you : (20+1)/1 = 21 times or 20 log21 = 26,4 dB
Another option is to change R14 value, with a 5k you get
(100K+5K)/5K = 21 times or 20 log21 = 26,4 dB
Ball park maybe
Best,
nAr
I think nar deserves some kind of award here... for helping out so many people in this thread! Good work!
It is always subject to caution ... and verify by your own experience ... I can make mistakes, epecially whilst doing 3 things at the same time
nAr
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