New TK2050 board

[alkasar]

Originally Posted by mravlca

Hi,

Which components need to be changed, are these only capacitors on the psu line? Why has to be gain changed, have the 517B and 508 different input sensitivity?

not only power supply line but also output filter caps & resistors. Also a couple of other resistor values need to be adjusted : the 5V regulator, led and I may forget about few others.

All the amps using tc2000 input chip have the same input sensitivity However, modulator feedback & gain should be adjusted according to power voltage. tk2050 datasheet explains page 12 http://www.datasheetcatalog.org/data...h/mXyzwqtx.pdf . Typically increase Rfbc with higher voltage, which increases also gain.

Regarding heat dissipation I won't have a problem as the board will dissipate heat through aluminum block to the chassis.

interesting. how do you do that ? can you show a picture ?

[mravlca]

Thank you very much for the explanation. So changing to STA510A can be much more easily made.

Originally Posted by mravlca

Regarding heat dissipation I won't have a problem as the board will dissipate heat through aluminum block to the chassis.

Originally Posted by alkasar

interesting. how do you do that ? can you show a picture ?

I can't show you the picture as I haven't done this yet. But this aluminum block would be the same size as it is now heatsink. It would be bolted from bottom side to PCB and on the top side to chassis or something that has bigger heat dissipation.

[liberas]

Hi all,
Does anyone have any experience with cheap attenuators (Valab and others) from ebay? Is it good option to replacement standard pot in tk2050 (t1/t2) boards? Or Alps is a better solution?

BR,
Rafal

[alkasar]

Originally Posted by mravlca

Thank you very much for the explanation. So changing to STA510A can be much more easily made.

yes. you can copy what Hifimediy did for T1-510A

[Jack Caldwell]

Originally Posted by alkasar

not only power supply line but also output filter caps & resistors. Also a couple of other resistor values need to be adjusted : the 5V regulator, led and I may forget about few others.

All the amps using tc2000 input chip have the same input sensitivity However, modulator feedback & gain should be adjusted according to power voltage. tk2050 datasheet explains page 12 http://www.datasheetcatalog.org/data...h/mXyzwqtx.pdf . Typically increase Rfbc with higher voltage, which increases also gain.

Could you share the values you specified for these components? Since the 2x510a you got is stable, I'd be interested in getting something similar. I can probably figure decent values to work with from the spec sheet, but it would be most useful to start with values that have already proven to work well.

Also, is the 510a functionally equivalent to the TK20250, same gain settings, etc?

Thanks!

[erozsolt]

Is there any reason to choose the 2 x 80 W model from T1 over the 2 x 100 W one? I mean over the 6 USD savings. Is the 2 x 100 W model with sta510A better in every way? I will buy the matching SMPS, so the PSU is not a restriction.

[Jack Caldwell]

Originally Posted by alkasar

I am also sure that the T1-510A version, using STA-510A power chip, would have made the difference even more obvious.

I have the pleasure to own a custom made T2 with 2x 510A power chip, and it performs much better than the regular T2

Hi Alkasar, in looking over your comments about the paralleled 510a, I noticed that hifimediy have released a T3 using paralleled 517B output sections.

Have you had a chance to compare between 510A and 517B?

Although I am aware of the 3020, I am trying to evaluate only amps that have the 2000 type controller in them, as Vinnie at RedWine Audio told me that it is the best sounding of the Tripath controllers and his amps are among the best ever, so I trust his ears and acumen. Big $$$ but good sound!

So my thinking is maybe to jump to the T3 from the beginning...

[alkasar]

hello,

@liberas : I have a Valab23 stepped attenuator with smd resistors (log, 50K) excellent quality. good fit with T2

@erozsolt : in my optinion, go for T1-510A with associated power supply.

@jack :
yes T3 has paralleled sta517B. its a mono design. Bernie7 on this forum built an amp with two of these boards.
It has plenty of power

I did not need that much power and wanted a smal design, 4ohm load capable, with single smps. Thus the T2-510A custom build.

I never listened to a 517B board. I would love to compare it with a ta3020 amp as they play in the same league regarding power

I have listened to other popular tripaths ta2020 and 2022 and I agree that tc2000 based amps have best sound. (Ta2020 is not bad at all, but really lacks power). TA3020 is supposed to have the next evolution of tc2000 inside (a modded tc2001 actually). It has very good reviews actually. It may be my next try

T2-510A board :
We agreed with hifimediy on the feedback resistor Rfbc adjustment. This is R12/13/14/15 on the board. They are now 19.2k instead of 14k. With this change, T2-510A gain is 20v/v instead of 15 before.
Hifimedy made other housekeeping changes (resistor on the 7805 regulator, relays, capacitors voltage, etc.) I can't list for sure all the changes he made but he knows .

[erozsolt]

Does anyone have any experience with the SMPS300R from Connexelectronic? Or generally with any SMPS from Connexelectronic? Would you recomment it over the Meanwell one?

Do I need anything else then one board of ALPS-T1-T510A and one PSU for example from Meanwell or Connexelectronic? I mean a case and some plugs of course, but anything more?

@alkasar: Thanks!

[col]

I have a modified ConnexElectronic SMPS250 (one of the older ones) it works very well and is much smaller than the "brick" SMPS. I think Cristi has created one SMPS that is single ended so you don't have to modify it, SMPS500R-Single.

col.