// TDA1541A PCB already

[Coulomb]

Re: Re: Just got my kit!

All I need to do now is track down a good 18V-0-18V/ 50VA transformer and an attractive case.

Anybody in the US have a good source for an affordable transformer and case?

Here, only one left:

http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=95B5012&N=0

Ouch to expensive, try this one.

http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?Ref=43445&Row=444529&Site=US

Regards

Anthony

 

[darkmoebius]

Re: Re: Re: Just got my kit!

Thanks for the tips, guys.

Ouch to expensive, try this one.

I was just looking at the .pdf catalog for that one as you posted - $19, fug-gedd-ha-bout-it!! Great deal.

BTW, they have a much smaller encapsulated PC mount 18V CT/50VA toroid(TE70084-ND) that measures 3.2"x3.2"x1.5" for $28.

Is there any benefit of downside to PC mount transformers?

I don't mind the $9 because it will allow me to use a much smaller chassis.

 

[Coulomb]

Re: Re: Re: Re: Just got my kit!

Thanks for the tips, guys.



I was just looking at the .pdf catalog for that one as you posted - $19, fug-gedd-ha-bout-it!! Great deal.

BTW, they have a much smaller encapsulated PC mount 18V CT/50VA toroid(TE70084-ND) that measures 3.2"x3.2"x1.5" for $28.

Is there any benefit of downside to PC mount transformers?

I don't mind the $9 because it will allow me to use a much smaller chassis.

I have both version in stock, I prefer the wired toroid for point to point work. The encapsulated is a nice package, but the tiny pins that are meant for PCB mounting are a pain to wire to. You could mount it on a peice of Perf Board I suppose. I am considering etching a basic PCB for mounting the four required for my CD Player. I am not very proficient at making PCB's and usually rely on paying someone else to do it for me. Lately that has not been working out to well either.

BTW the Transformer is held in place with a single 4MM screww from the underside.

Regards

Anthony

 

[finneybear]

Re: Re: Re: Re: Just got my kit!

Thanks for the tips, guys.



I was just looking at the .pdf catalog for that one as you posted - $19, fug-gedd-ha-bout-it!! Great deal.

BTW, they have a much smaller encapsulated PC mount 18V CT/50VA toroid(TE70084-ND) that measures 3.2"x3.2"x1.5" for $28.

Is there any benefit of downside to PC mount transformers?

I don't mind the $9 because it will allow me to use a much smaller chassis.

Well, these are mini-toroidals, not your regular power toroidals.
There are good and bads about mini-toridals so it's your call.

Another good place to get is Parts Express. Those Avel trans are
very good and the prices are fair, too. Unfortunately, for 18V,
they only have 160VA one in stock.

Why not just ask Thomas for help? He's kind enough to
custom make one 110V R-core trans for me. The price
is very good, too.

 

[darkmoebius]

Toroid transformer

Well, these are mini-toroidals, not your regular power toroidals.
There are good and bads about mini-toridals so it's your call.

Then, I'll just go for the standard "thin" style. I just laid out the PCB boards and tried to figure out the smallest footprint. The heatsinks and output tubes throw a little curveball into my plans. No biggy, I'll just look around for a ~14" wide enclosure.

Why not just ask Thomas for help? He's kind enough to
custom make one 110V R-core trans for me. The price
is very good, too.

I had no idea he's a one-stop shopping center. Hell, I'd have had him toss one in with the rest of the kit. I'll just grab the $19 job from Digikey since I need to order some other parts for an amp I'm building.

Now, that Thanksgiving is over and things should be getting back to normal in a day or two, I'm shooting for Sunday as "DAC building day". I'll borrow a digitall camera from my neighbor so you guys can have a good laugh at my soldering skills.

 

[finneybear]

Here are some Photos of my progress so far on the Dual DAC Project.

...

Regards

Anthony

Anthony, beautiful work! Just wondering what those
yellow 0.1uf caps are? How about the resistors R22, R16, R49,
and R50 on the tube board?

Just got my kit from Thomas and am now thinking about
changing parts. Found this place on web, they seem
to make decent PP caps:

http://home.kimo.com.tw/ucccap/ucccap.htm


Definitely I will use 22uf+22uf config for C3 and C43 on
the tube board. Probably get several small 0.1u for
by-passing. Also plan to build my own 18V power
regulation board then feed it through C7 and C8 to the
main board.

For the tube board, I will use Riken for the main resistors, too.
C29 C30 C49 C50 will be BlackGate N. M cap for C23 C24 C42
C48. Jensen copper for output coupling.

Has anyone ever thought about dropping T1 and putting
in a CDE 10000pf mica instead? How about Caddock TF02
for I/V, R28, R39, R47, and R48?

Another main concern is the connectors. Any good connectors
for J8/J10 tube board, J2/J3 main board? The space is
very tight. Probably I should just solder the wires directly?

Oh, and how about L3 and L4 on the tube board? Any one seriously thinking about replacing the stock resistor there?


Thanks.


-finney

 

[finneybear]

Re: Toroid transformer

I had no idea he's a one-stop shopping center. Hell, I'd have had him toss one in with the rest of the kit. I'll just grab the $19 job from Digikey since I need to order some other parts for an amp I'm building.

Now, that Thanksgiving is over and things should be getting back to normal in a day or two, I'm shooting for Sunday as "DAC building day". I'll borrow a digitall camera from my neighbor so you guys can have a good laugh at my soldering skills. [/B]

Well, Thomas was very kind to me this time for all of
the hassels. I also had to wait for a few months just
to get the trans. So, it should be the last resort kind of thing.

Looking forward to your progress photos. Probably I will
post mine here, too, as soon as I start the work. Have
two 1541 S2 waiting sideline now.

 

[Coulomb]

Hello Finney, the yellow caps are Wima caps from Germany. The resistors are Vishay-BC Components. The light blue Resistors are Panasonic and the darker blue resistors are Ohmite. My Coupling caps on the output are Hovland.

Thanks for the feedback, I have gotten a lot further with the project as it is almost completed now. I will post some more pics soon. I too was thinking of implementing the inductors instead of a resistor, but I am unsure of what value to use.

I often use the Mini Toroids from AMVECO and I am very happy with the results.

Regards

Anthony

 

[roibm]

How much did you guys pay for the kit + shipping and what did it include?

 

[Coulomb]

How much did you guys pay for the kit + shipping and what did it include?

I Paid $250 US which included a few upgrades and shipping. The kit includes everything except transformers and a chassis.

Regards

Anthony

 

[finneybear]

Hi Anthony

Much thanks for the info. So those yellow ones are Wima MKYs?Where can you still find them? How does Ohmite 40 series resistor sound? Have never used it before!

Just did some simple calculation, around 100uH to 10uH will be fine for L4 and L5. Since they are part of the simple LPF, they will have huge impact to the final sound. Also here you can have tons of tricks to play. I am a bit lost now and would love to hear some advices...


-finney

 

[Coulomb]

The spare set of DAC boards that I had from Thomas have been sold.

Thomas I will send the funds in a few days.

Regards

Anthony

 

[darkmoebius]

Time to wake up this thread!!!!

Here are some Photos of my progress so far on the Dual DAC Project.

Is this for balanced/differential output?

I'm redoing my system in true balanced operation and was wondering how this PCB could be run in that fashion?

 

[Coulomb]

Re: Time to wake up this thread!!!!

Is this for balanced/differential output?

I'm redoing my system in true balanced operation and was wondering how this PCB could be run in that fashion?

Thomas's design is single ended.

Regards

Anthony

 

[darkmoebius]

Re: Re: Time to wake up this thread!!!!

Thomas's design is single ended.

Yep, I noticed, but couldn't understand why you are building a "dual dac".

Now that I look at the pictures you posted on the other thread, I can see that there is only a single set of boards.

Sorry about the stupid question.

I still haven't had a chance to solder up my kit yet, but I hope this weekend.

 

[dw1narso]

Dear Thomas,

when do you think the version 2 will be available?

REgards,
---
David

 

[Coulomb]

BTW, I can not get my Tube BUffer Working. I have no B+ from the 6X4! I have 540 VAC across pins 1 & 6 and 6.3VAC on pins 3 & 4. I should see the B+ across C4.. Nothing, the tube does not even light up or get warm. I have tried 3 different tubes.

This is the original Tube Buffer Board, I did not do the 6X4 rework as I was under the impression that was not required if I was not doing the Voltage Doubler change.

I have not done the 6DJ8 mod either, I assume that is not required if the VD mod is not done.

What have I missed?

Regards

Anthony

 

[Areman]

Hi,

My name is paolo and i write from italy.I'm interessed to build a a DAC and also i have 4 tda1541a chips and 1 CS8412.Well.Now i want to build it into a PCB that permit to use this chip's.

Do we know were i can find a PCB fort this type of DUAL dac?

I have tested the PCB of Torbens at http://bygselvhifi.dk/index.htm but the resistor of the TL431 became very hot and o don't know why.

Thank'you to all...!!!!

Paolo

 

[Areman]

Dear all,

First of all. I would like to say sorry to Pedja because my design of this KIts which use AD844 OP-amp output stage was samilar to his design. Although the working condition, selection of chips
Pedja use J-fet, I use regulator IC was different. But the circuit design is similar. After the judgement of Jean-paul( moderator). The previous thread was closed & I can not amend any informations to the 18 buys of this kits.

To prevent for any or further agruement. The C board of my PCB will not further sold to any diyers. If U like the AD844 OP-amp output stage. pls ask for pedja, But Pedja's design which compare to me had some different. He use one TDA1541a but I use Two,working in parallel condition. The Best that I can was I think My PCB was one of the Best that in DIY DAC.

For My design pls visit.

http://johnson.tmfc.net/audio/file

The AD844 Schematic was still in this file. But this is for your reference only. I WILL NOT PROVIDE ANY PCB OR SUGGESTIONS FOR AD844.

The multiple output stage for different tubes was my design.

Also, I will post my new deisgn for the RE-clock circuit in this forum first to prevent any agruement as previous THAT involve the copyright with others.

At last I would like to say that my design or kits will not assume EARN MONEY. I only hope to PROVIDE the BEST Price/cost ratio to build kits to DIYERs.

An excellent circuit need high quality parts, otherwise cannot perform its really condition.

Photos shows is the previous photos about the full look of the DAC.

I still test some parts for improvement. I will continous amend it.

thanks

thomas

Hey this PCB seem good!.Were i can find this PCB?

Thank's

Paolo

 

[tube-lover]

hi your PCB was ver.1 only, now is ver.3 coming. pls visit group buy for ver.3 will be a funish prioducts & wll had 80% nickel core transformers output.

thx

thomas