// TDA1541A PCB already

[tube-lover]

Dear all,

the first order of 12 pcs of TDA1541a S1 which I order from Holland is arrived. They all remove from old machine but unused.
The company told me was remove from Philips high grade parts wihch were repair stock.

I hadn't any instrument to test them but I made a simple hearing test compare with the standard TDA1541a. I only hear the background is more silience, little bit of punch dynamic was increase & little smooth sound stage. I can only hear will 6~8% inprovment.

But it actually quite good.

pls see the photos.

dear ftjandra,

If U like me to advise U, I will advise r-core than toroidals.


thanks

thomas

[Coulomb]

Thomas, how much for a pair of those S1's?

Secondly, if I just want to run 6.3VAC fillament do I have to do any of the tube mods or can I just solder all the sockets striaght in?

Regards

Anthony

[Coulomb]

Originally posted by Coulomb
Thomas, how much for a pair of those S1's?

Secondly, if I just want to run 6.3VAC fillament do I have to do any of the tube mods or can I just solder all the sockets striaght in?

Regards

Anthony

Thomas any comments?

[pburke]

Originally posted by tube-lover
For peter & SS1,agent.5,

pls email to me for detail of the kit.

thomas@diyaudiocraft.com

thnaks

thomas

I did - about a month ago, but so far have not received an answer. Maybe my junk mail filter ate your message?

Peter

[tim pattinson]

Anthony, re. your filament change-I just lifted the pins in the end and ran tightly twisted cable directly to the tubes' sockets. Have you tried the 6c45pi's?

Have to admit I've done so many mods on the tube buffer, that it's not a lot like the original...Auricaps on the outputs [1mF], ordered Constant Current Supply kits from Kand K audio, AC filament heating...Rikens in the signal path...thank goodness the PCB quality is so fabulous.

Thanks to all people who have suggested mods...every one of them has made some difference.

I also noticed that Rockna is now doing a clock:
www.rockna-line.com/diy/uclock/clock.htm

[tube-lover]

Dear all,

Very long time that hadn't post any message for the kits.

I was too........oooo busy.

Now, a small amend for the kits.
I must did it( amendment for the kits) because I sell over 80 set of kits already.
Very thanks for all the Hong Kong diyer & oversea's support.

Dear Anthony,

U can directly use AC 6.3V for tubes filament. The sound will more active. I test this before but I was afraid that will increase teh noise. So I still advise use DC for tubes filament.

For the S1 single Crown. I cont' run in over ten days. very stable & hadn't any noise. After run in the sound stage was little bit smooth than standard 1541a.

I compare the R1, standard & S1. Some peopletold me that they trusted that the sound quality of S1 will be better than S2 because S1 was select by Holland Philips & was the highest grade in the previous production stage. The S2 was produced in Taiwan & was select in Taiwan. But this reason nobody can proved it right or not.



Peter, pls email to me one more time because I had only 10 set remain in hand. The small adjust for the parts was now will suggest the ERO MKP caps change to Aerovox 400V 3.3uf.
This caps was from USA military storage & still had telfon tube coated for lead out. I compare this cap with the ERO. ERO had very clear texture, this cap had better bass than ERO. The sound density will little much better than the ero but will not like Solen not clear low bass area sound.


this is my email.

thomas@diyaudiocraft.com.

Tim, although I can match the same date code of the DAC. BUt I still cannot make sure that the DAC was absolute match for their private clock in the DAC. so the jumper below the I2S was connect or broken to adjust the sound.

Another that will quite large effect the sound was the R43 & R52 of the tube buffer board. Standard is 470K 2W.
Pls try to adjust to 680K~Below1M. The sound will had large different. Adjust by your private Taste.
I suggest to use the RMA~ RMG. sure will much better. Not use Carbon film resisters, otherwise the sound will fog.


The last advise to amend was suggest by cmt42001 which use the 1.2V rechargeable NIMH cell for 6c45 bias. It only run in ~10ma. The cell most was over 1300mah. During working will be same time charge for the cell by the DAC. So it means one full charge cell can working over 1~2 months that not need to re-charge.
what is the different???

the deeper of the Bass is large improve. More detail HF, LF.
BTW, the different was large than U charge the caps.

Pls try.

For more detail ask cmt42001.


I was testing the DIY CD Drive. I use magnetic float. but some problems still not pass. I need your help!!!

thanks

thomas

[Coulomb]

U can directly use AC 6.3V for tubes filament. The sound will more active. I test this before but I was afraid that will increase teh noise. So I still advise use DC for tubes filament.

So I can build the board without any of the tube mods?

Regards

Anthony

[tube-lover]

Dear Anthony,

yes, U can try to do this. after compare the different between standard or mod. Pls call me back the result .
Pls try to adjust the resisters that I advise.

Anthony, pls email the commerical invoice to me once again as previous that U need I fill & fax back to custom.

The first set of DAC kit that I post to U still hold in the custom.
I need to collect back but the local post office in Hong Kong need I send this received to them for follow up. Pls email once again to me.

thanks

thomas

[Coulomb]

I have an extra kit in hand due to some shipping and Customs issues. Thomas would like me to sell it for him to someone in North America, preferrably Canada, rather than ship it back to Hong Kong. Please contact me via email if you are interested, the funds would be sent to Thomas directly and when he confirms receipt of funds to me I will ship to the purchaser.

Regards

Anthony

[Peter Daniel]

Well guys, I finished yesterday the DAC and SS output boards and I must admit that I'm pretty much impressed. Not only the quality of the board is first rate, but also the sound coming from this design is very good too. I'm scared to think what it will be like with all the mods I plan to go with.

Originally, I tried A grade DAC chips supplied with a kit and by itself it was fine already. Later, I placed S2 chips and it improved even more (smoother and refined).

And I'm pleasantly surprised that two chhips in parallel sound indeed better than a single chip. The difference is quite substantial.