Linn Numerik upgrades

[dobbie-t]

Has anyone played about with the components in a Linn Numerik, perhaps some extra regulators, a newer clock and a change of the opamps ?

[Valery]

Mostly nothing to do except changing all lytic capacitors if it's about 10 years old. Regulators LM317/337 to LT317/337 and LM2940 to TL780-05. Maybe you'll have to adjust a little +15V with a blue pot. What DAC chips are in your Numerik - PCM63 or 1702?

[dobbie-t]

I have the PCM63 chips, I was a little wary of changing the capacitors because I don't want to loose the Linn sound from the DAC and was under the impression that the capacitors made a huge difference to the type of sound I could expect, where as the upgraded clock and regulators would just make what is already there better. Any thoughts if that is true or not ?

[Valery]

Yes, for sure. That's why I changed Rubycon on just new Rubycon's RX30 type (not Black Gate's or other special for audio). In comparison new capacitors gave more tight bass but the overal Linn sound remains.
I have PCM1702 DAC chips inside but I want to try to put on PCM63 as I have them too. But I have to install some missed details on the board in this case and the onle two that I don't know nominals are capacitor C216 and resistor R204 (maybe 2K4 as on the board with 1702). If you wiil open your Numerik then make me a favour, please - let me know the nominals, O.K.?

[Valery]

Marked red

[Valery]

As for the Numerik clock upgrade then this is completely not so easy as in a CD player. It has two crystals in a "box" with SAA7274 chip, then we have to know schematic first (it's better to know schematic always first in any way ).

[dobbie-t]

I'd love to do that for you but unfortunately all my Hifi is in storage whilst I move, it will all be out in a few weeks time when I'll get it open and take some photographs for you. I'm just putting together a list of to dos at the moment for when it all comes back out. Can I ask why you want to change the chips on what seems to be a downgrade ?

[dobbie-t]

Ah, I was wondering why there was nothing about clock upgrades online. It seems that Linn keeps its service manuals out of the public domain so that might be a bit of a non starter. I'll try phoning Linn but I'm not hopeful. Perhaps the regulators and the cap change will give me what I am looking for at the moment though, I will know more when I finally get my life out of boxes. I am also thinking about taking the clock output and then trying to get it to sync up with my USB-SPDIF converter so I can get the benefits of a Karik and of itunes.
http://www.head-fi.org/forums/showthread.php?t=113102 seems to say that it is possible.

[Valery]

Originally posted by dobbie-t
I'd love to do that for you but unfortunately all my Hifi is in storage whilst I move, it will all be out in a few weeks time when I'll get it open and take some photographs for you. I'm just putting together a list of to dos at the moment for when it all comes back out. Can I ask why you want to change the chips on what seems to be a downgrade ?

Well, I read a tests of Linn Numerik in different internal integration but non of them witn PCM63P-K and Brilliant SMPS together. The Burr-Broun PCM63 is widely known as one of the best DACs and PCM1702 is the follower with slightly worse parameters. As this is the matter of taste then someone can love it sound but in "audio fields" commonly desired that 1702 is worse. So I have a possibility to compare, with your help.

[Valery]

Originally posted by dobbie-t
Ah, I was wondering why there was nothing about clock upgrades online. It seems that Linn keeps its service manuals out of the public domain so that might be a bit of a non starter. I'll try phoning Linn but I'm not hopeful. Perhaps the regulators and the cap change will give me what I am looking for at the moment though, I will know more when I finally get my life out of boxes. I am also thinking about taking the clock output and then trying to get it to sync up with my USB-SPDIF converter so I can get the benefits of a Karik and of itunes.
http://www.head-fi.org/forums/showthread.php?t=113102 seems to say that it is possible.

Eahh, I'm also tried to mail Linn, they told me that my dealer in Moskow will be more than happy to answer all my questions but for some strange reason they were not . I'm understood that I'm not a Queen Mary (ocean liner with Linn all round-around) and just relaxed. Attached articles gave me thó direction to move, so while your Linn in the boxes I'll try to find out more information. Till now it look's like that sync out carries WCKO (output timing control) signal from pin 27 of digital filter DF1700. It comes out in TTL level (that we need) but amplified then with two transistors to level 10v in order most probably noise protection.