The Sugden SDT-1 player is a normal TDA1541/SAA7220 arrangement, but I don't see a SAA7310 chip; either I've missed it or something else does the same functions.
I have reworked it with very many good quality new caps (oscons near the dac chip) and changed to NOS by simple wiring as usual. Results are good.
I now intend to upgrade the clock and, even after lots of reading, I'm still confused about clock distribution, different frequencies etc.
But the mists may be clearing after reading good info here, and study of the SAA7220 datasheet.
I see that the TDA takes clocks lower than the 11.289 MHz, but in NOS connection the right frequencies must be coming from the 7310 or similar source.
The 7310 takes its clock from SAA7220 output on its pin 9, and the 7220 datasheets shows this as 11.2896MHz. So I guess the 7310 (or whatever I have) itself derives the lower clock frequencies and, in NOS mode, these are passed direct to the TDA; so all clocks are in synch.
It seems to me that if I remove the SAA7220 and simply connect a new clock in place of the 7220 clock output on pin 9, it should work.
The SAA7220 plugs in, so I can try the following. Remove the 7220. Mount the clock board on a piece of plastic and glue this to the top of a DIL plug, wire the clock + to pin 9 and the clock - to pin 12 (earth). Seems to me this will work and will give benefits of a better clock, though perhaps not quite as good as the complex schemes I've seen of frequency dividers and rewiring of all the clocks.
Am I on the right path? Looks worth trying, as I've seen this player criticised for having a poor clock.
By the way, it is lampizated with excellent results! 6SL7 / E80CC mu follower at about 2.5mA, 165V across the 6SL7, 115V on the E80CC, 24kohm anode load.
I have reworked it with very many good quality new caps (oscons near the dac chip) and changed to NOS by simple wiring as usual. Results are good.
I now intend to upgrade the clock and, even after lots of reading, I'm still confused about clock distribution, different frequencies etc.
But the mists may be clearing after reading good info here, and study of the SAA7220 datasheet.
I see that the TDA takes clocks lower than the 11.289 MHz, but in NOS connection the right frequencies must be coming from the 7310 or similar source.
The 7310 takes its clock from SAA7220 output on its pin 9, and the 7220 datasheets shows this as 11.2896MHz. So I guess the 7310 (or whatever I have) itself derives the lower clock frequencies and, in NOS mode, these are passed direct to the TDA; so all clocks are in synch.
It seems to me that if I remove the SAA7220 and simply connect a new clock in place of the 7220 clock output on pin 9, it should work.
The SAA7220 plugs in, so I can try the following. Remove the 7220. Mount the clock board on a piece of plastic and glue this to the top of a DIL plug, wire the clock + to pin 9 and the clock - to pin 12 (earth). Seems to me this will work and will give benefits of a better clock, though perhaps not quite as good as the complex schemes I've seen of frequency dividers and rewiring of all the clocks.
Am I on the right path? Looks worth trying, as I've seen this player criticised for having a poor clock.
By the way, it is lampizated with excellent results! 6SL7 / E80CC mu follower at about 2.5mA, 165V across the 6SL7, 115V on the E80CC, 24kohm anode load.
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There are some pics in that thread, but only of the prototyping. You can check the schematic to see how clock is distributed!
Many thanks!
This is useful as I'm mainly a vinyl and valve person, learning a bit about CD.
As I've made very many valve amps, preamps, phono stages and headphone amps I'm confident doing valve outputs for CD players; done two now, working on my 3rd.
Just for info; I absolutely love upgraded TDA1541A players with valve output stages; just so musical and analogue sounding, up there with really good LP and that's quite an admission from a vinyl junkie!
I'll let you know how it goes I've already started the clock mod.
This is useful as I'm mainly a vinyl and valve person, learning a bit about CD.
As I've made very many valve amps, preamps, phono stages and headphone amps I'm confident doing valve outputs for CD players; done two now, working on my 3rd.
Just for info; I absolutely love upgraded TDA1541A players with valve output stages; just so musical and analogue sounding, up there with really good LP and that's quite an admission from a vinyl junkie!
I'll let you know how it goes I've already started the clock mod.
Yes, basically your new clock goes to pin9 of the SAA7220 socket - from there usually the other components take the clock signal.
Bloody hell, it works!
It's hard to say much about the sound yet, until all is warmed up and also I need to get used to it. But I can say it sounds nice, perhaps wider image, good rhythms; but generally improved, I think. But I need to listen more to let the changes come through, I rarely get the full picture on a first listen.
Here are pictures.
The components Tent board and PSU, with my bases to mount them.
Bases fitted.
The DIL connector wired, signal to 9, earth to 12; there is no other earth connection from the board or PSU.
PSU fitted; glued in with silicone sealer; OK, does nor look professional but I use it a lot, it works well.
Connector sealed up. Yes, it looks awful! I should be ashamed but I'm not as it works OK. I could not get the cover on, best I could do was to cut it down and fix it as shown and then fill in the space with silicone sealer as strain relief. It works.
Overall picture. The part at the rear with aluminium cover holds most of the PSU for the valve output stage. On the right you can see the valves and circuit. The clock board is laying there, I'm about to fit standoffs and secure it.
There is no doubt that this one of the very best CD players I've ever heard. Probably the very best. Better than my Pro-ject RS2T transport and Aqua La Scala, and that is excellent.
More later.
Thanks folks!
It's hard to say much about the sound yet, until all is warmed up and also I need to get used to it. But I can say it sounds nice, perhaps wider image, good rhythms; but generally improved, I think. But I need to listen more to let the changes come through, I rarely get the full picture on a first listen.
Here are pictures.
The components Tent board and PSU, with my bases to mount them.
Bases fitted.
The DIL connector wired, signal to 9, earth to 12; there is no other earth connection from the board or PSU.
PSU fitted; glued in with silicone sealer; OK, does nor look professional but I use it a lot, it works well.
Connector sealed up. Yes, it looks awful! I should be ashamed but I'm not as it works OK. I could not get the cover on, best I could do was to cut it down and fix it as shown and then fill in the space with silicone sealer as strain relief. It works.
Overall picture. The part at the rear with aluminium cover holds most of the PSU for the valve output stage. On the right you can see the valves and circuit. The clock board is laying there, I'm about to fit standoffs and secure it.
There is no doubt that this one of the very best CD players I've ever heard. Probably the very best. Better than my Pro-ject RS2T transport and Aqua La Scala, and that is excellent.
More later.
Thanks folks!
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I've just had a listen, relaxed, not trying to evaluate and the improvement hit me like a hammer; a substantial improvement in sound quality.
A more powerful solid sound; better definition to instruments (where did some extra ones come from?); good rhythms; and an impression that something in the way of the music has been removed to good effect. Fine tonality, and superb female vocals, spine tingles.
But in a sense the above misses the point, which is that the music is fabulous and I love it.
I often need to adjust to a change in order to hear an improvement; this has now happened.
A more powerful solid sound; better definition to instruments (where did some extra ones come from?); good rhythms; and an impression that something in the way of the music has been removed to good effect. Fine tonality, and superb female vocals, spine tingles.
But in a sense the above misses the point, which is that the music is fabulous and I love it.
I often need to adjust to a change in order to hear an improvement; this has now happened.