Sorry folks I know this sort of thing has been covered here but I cant find anything this specific, I purchased this little drop in replacement for the filter chip but I would love to know what it does exactly, I asked the vender and I didnt get a very good response, "it reclocks and buffers the signal and sounds amazing" So I took it apart and drew the connections, I know its a Flip Flop and an Inverter/Buffer but can anyone with experience here say if its actually doing any good? Ive been reading about DEM reclocking and the mighty NOS thread for a while but my head is spinning. 
When I started the thread title one other thread popped up about the 74hc175N but had never got answered.
Alan
When I started the thread title one other thread popped up about the 74hc175N but had never got answered. Alan
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Many Thanks Mike, its very subjective isnt it, I think it has as many fans as it does haters. My guess is it depends on how old you are and how far your hearing has rolled off. Im going to get one of the VALAB clocks that feed all 3 chips from what ive gathered and I will probably give that a go with dedicated supplies for all, I had GD Audio bias a load of class A power supplies for a TDA machine many years ago, they have been sat in my parts bin, Im getting back into tweaking again.....
I don't know what that reclock PCB is???
Anyway ...
Agree w/Mike P that sound is better than NOS (imho) if you treat 7220 with the respect it deserves:
Don't use the 7220's Xout. If you're following with TDA1541, use a dedicated divide-by-2 circuit. I posted on specific /2 elsewhere on DIYA.
Oh, and you are using a good clock, right?
Also see Martin Clark's comments:
Is the SAA7220P/B really that bad ?
SAA7220 + TDA1541 (comment and questions) | pink fish media
Anyway ...
Agree w/Mike P that sound is better than NOS (imho) if you treat 7220 with the respect it deserves:
Don't use the 7220's Xout. If you're following with TDA1541, use a dedicated divide-by-2 circuit. I posted on specific /2 elsewhere on DIYA.
Oh, and you are using a good clock, right?
Also see Martin Clark's comments:
Is the SAA7220P/B really that bad ?
SAA7220 + TDA1541 (comment and questions) | pink fish media
Thank you hollowman, I will be reading these 2 links in a moment, yes ive got a Audio-gd Kingwa clock, had it at least 10 years but reading all this stuff about dem reclocking has got me thinking I need the VALAB one or I need to install another divider for the 5.6, thing is the Kingwa has a much better power supply, fully discrete class A, also been reading here how important the supply is so I keep reading....
The hell with DEM reclocking ... just put a good cap with appropriate value on the 1541 DEM pins. As the datasheet suggests.
If you've got time to kill, invest it in building dedicated pwr regulators for each IC's power pins.
Agreed, with regards to the DEM oscillator all you need is a good quality film cap of between 470pF and 680pF between pins 16 and 17.
Ignore the recent trend on this forum of using a much lower value cap (higher oscillator frequency), all you'll get is more distortion at low frequencies (it's in the datasheet!).
Cheers hollowman, I have sooo much TDA stuff including CDP's thats been sat around for donkeys, these regs where meant for my keeper....
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You have both convinced me and thanks for that, I am spending more time reading than actually doing anything, I need to sell some of my CDP's, Ive been hording for too long and i will probably be dead before I finish all my projects! It seems from what I have read that the Grundig mod is worthwhile, would you guys agree? It doesnt seem to have a cap between the 2 pins though so did you do both?
All my TDA players seem to have a cap on these pins already, obviously SMD, is the upgrade related to the type of capacitor or is it related to machines that didnt have it fitted already?
Thanks for the reply, I followed Lukasz from the early days, I don't see a link to the DEM cap and his works, he has helped me a lot in building an ultimate valve output stage but I think he has limits and also issues, he always recommend 100r IV resistor, way too high in my opinion, also backed up by data. I am going to reclock the cdp.
Alan
I fitted one of these NOS Reclock modules into my CD-60SE a few weeks back, the change suits me regarding what sound I like. Though after fitting the mute function was bypassed so had to add a wire from SAA7310GP to pin 23 I think it is of the SAA7220 socket, the guide was on the Lampizator site.
Other changes have been taking the signal from after the first half of the dual Op Amps (OPA2406) through some quality film caps to RCA's, socketed the TDA1541A position and replaced with a single crown type. Decoupling caps changed and SMD ones removed and 1uf on MSB and the rest .33uf films. A number of caps in the digital section changed to oscons and two of the stock reg's changed to Sparko Labs discrete reg's.
Other changes have been taking the signal from after the first half of the dual Op Amps (OPA2406) through some quality film caps to RCA's, socketed the TDA1541A position and replaced with a single crown type. Decoupling caps changed and SMD ones removed and 1uf on MSB and the rest .33uf films. A number of caps in the digital section changed to oscons and two of the stock reg's changed to Sparko Labs discrete reg's.
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Now you might want to pull those 1Uf MSB and 0.33uf films to try the 50hz DEM mod 
You decoupling will need 14X 100uf 25v low leakage
For oscillator 1X 1uf and 1x 12k
Building the ultimate NOS DAC using TDA1541A
You decoupling will need 14X 100uf 25v low leakage
For oscillator 1X 1uf and 1x 12k
Building the ultimate NOS DAC using TDA1541A
Not really.
For a few reasons, mainly as reworking these old Philips boards can be a recipe for mess.
I have read through that thread, but not all of it as a lot of it bounces around from one topic to another, I ended up going the way I did as I already have the suitable parts and am also on a limited budget.
But I will read some of that thread again, as I am still doing in relation to anything regarding these old players using the TDA1541A chip.
Still, thanks for the heads up
For a few reasons, mainly as reworking these old Philips boards can be a recipe for mess.
I have read through that thread, but not all of it as a lot of it bounces around from one topic to another, I ended up going the way I did as I already have the suitable parts and am also on a limited budget.
But I will read some of that thread again, as I am still doing in relation to anything regarding these old players using the TDA1541A chip.
Still, thanks for the heads up
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Nicely done, Ive been playing with these machines for years, I still have a couple left but I dont listen to CD's anymore. I replace every cap on these old boards, their getting on now. I also do the lampizator output stage. This is a rotel 855, already good 220uf around the DAC, I change last 2 to 470n and 2.2uf. I didnt have to do anything else after fitting the re clock boards, I make these myself now... Good luck and have fun.
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Nice, DawgNo1
The 855/955 are nice stock, a mate has a 955 (same) that I did the cap output on, I find I'm adverse to fitting extra supplies and such, maybe I'm just lazy
Lots of room in those Rotel players too!
Yeah lots of room but its a shame they soldered instead of plugging cables in, I find that a real chore. Have you seen the creek CD60? I have one of those, no need for more supplies, 16 highest quality Linear Tech voltage regulators, all locally placed not miles away like every other player, imagine upgrading those buggers, cost more than the player!