check out the 41Hz one or the DIY paradise ones. See how the layout of the output components are

This post has been edited by sakaic: Jun 25 2010, 10:18 AM

ooo understood now

hmm charlie is using 10uf as input cap? elna cerafine, i got those laying around tho

Oh yeah....I also removed the 1uF electrolytic from the input side.

yea, no idea y its there

but tht might be the course of the harshness?

I think its an attempt in increasing the input capacitance

Hey sakaic I noticed that you've the MKII instead of mine MKIII.
Since both are from the same guy, maybe I can also mod my board as per yours.

Please refer to output portion of the datasheet.. Check the red underlined 0.22,
Are you saying that originally, MKII comes with 0.47u and the you changed it to 0.22 as per the datasheet?




This post has been edited by cresstt: Jun 26 2010, 06:25 PM

yes. But check the impedance of your speaker. There is different value for different impedance. I also changed the value for cdo to datasheet value.

my itchy hands are contemplating to change the 2 caps on the MKIII output stage... They arent correct are they when referring to the datasheet ?





Attached image(s)

Look for the one in series with a resistor and check the value.
Then the other one is the one that you highlighted, the lower one is the other one i changed.
the other 220n I changed to a higher grade wima (syok sendiri)

refer to the datasheet then slowly trace back. Then you will see what is the same and what is different.

---

Added on July 1, 2010, 2:00 pmThread so quiet already?

was hoping for some feedback

This post has been edited by sakaic: Jul 1 2010, 02:00 PM

I have another version of 2020 datasheet. It stated both Co=0.47uf, Cz=0.47uf (not 0.22uf) and Ccm=0.1uf (not 0.01uf).
I have made the changes, the improvement is quite noticable in in high and mid range. I like the result.

Because of couldn't find better one, I tempolary use Wima 2.2uf 60V as input cap, power cap change to 220uf from 470uf and orginal indoctor remain. I think changing these 3 may improve more but lets wait and see.

The version of 2020 datasheet I got.


My MKIII caps all change to 0.47uf and o.1uf


The small 2.2uf Wima input cap and 220uf power cap


Please don't use default RCA cable supply with MKIII, change it immediately, huge improvement

nice kww....

but i tot bigger power cap = more bass?

changing those to .47uf makes the sound more analogue?

btw is the wima input cap better then the ori 1?

This post has been edited by xtorm: Jul 5 2010, 12:44 AM

Xtorm, changing the 0.47uf cap give smoother high and mid. The vocal didn't sound clinical and harsh anymore. I don't know is it analog.

Ya, the bass reduce after I change input cap and power cap. I am not sure which one affect it but I will change the input cap to obbligator once I found it someway in my store. The power cap is Elna cerafine, should be of better quality compare to the original.

cerafine is very good!! got some laying somewhere too...hahaha...

analog as in not so harsh an clinical, kinda like cd vs LP

abbligator...wow tht will surely make the whole thing sound smooth n nice...

will try to complete my casing next week as work at site has temporary reduce to 1 too bad the last MKIII is sold, might be using a ta2020 n mod it instead as for the pre-amp, will not make any changes as ill b using it to let them try out the sound during tt, i got a line out on my casing

0.47u is correct if your speaker impedance is 4ohm

Sakaic, you mean for 8ohm it should be 0.22uf and Cdo is 0.01uf (not as the datasheet 0.1uf)?

for the 0.22uf thats correct.

now i have a problem.......I have 2 versions of the datasheet

the one you showed is from the profusionplc website.

The other one I have is an earlier version hanging somewhere.

the value for the super small cap is different. The profusionplc shows 0.1uF and the other one says 0.01uf. I think I will follow the profusion datasheet.

Now have to change back. But the other caps are per the datasheet. there is a footnote at the bottom of the picture of the IC that states the value of the caps.

Swapped. THIS is the sound I was expecting.

Tighter bass.......dunno which *&#@er put that datasheet up......

The wrong version is numbered TA2020 – KL/7.1/03.05 at the corner of the page.

This post has been edited by sakaic: Jul 7 2010, 12:28 AM

I have tried both 0.47uf and 0.22uf on Cz. I like 0.47uf more in that position even my speaker is 8ohm. The vocal is fuller, warmer, thicker and bass is better. Beside that I also change an obbligator 2uf 650v to replace the wima at input cap, vocal is smoother, mid and low improve. Maybe it need more time but I think not much changes.

Overall I am satisfy with it after swap of the capacitors. There are a few failure but not worth mention.

After that I also do an AB test with 2024, I think it is close, but if listen careful enough, 2024 still win by a small margin, I think I am really bias, it is all in my brain telling me 2024 is good because i have been listening to it for few years already, I am use to it.

Here is the summary of thing I highly recommend to change for 2020 MKIII (don't ask me to use scope to proof it to you, I have only my ear to tune):

1. Don't use the RCA cable supply with it, swap with better cable.
2. Co change to 0.47uf.
3. Input cap must change to better one in range of 2uf-3uf (non electrolytic)
4. Cz is already 0.47uf but changing to a better brand will improve the sound.
5. Solder connect all cable, the cable socket supplied is of low quality.

Next upgrade I will consider is to use better inductors and better power supply of 150VA transformer with a simple CRC filter.

Good to know the thread is still alive!
kww, keep us posted with your progress.
I, unfortunately have stop playing with the T-Amps...

Jazzy, not much progress la. I am just doing 1 to 1 swap, noting much will happen.

12ax7 pre-amp