xtorm,
Good thread although I did not expect to be this soon!
what value did you use for your stereo pot? Linear or log?
Will you cover the power supply?
Maybe it would be nice if you mention where you source your parts.. if other than Jalan Pasar or SS2 la..

Thank you for the advice bsl!
Shortlist:
1. 100kohm Alps blue log pot
2. 'huge' PSU
Saw some great snubberized PSU for the GainClone, guess with 'little' mod should work well with the T-amp

Won't step volume pot costs a 'bomb'?
Expensive as you really need an audio grade resistors, am I right?
That 100k, alps or...

My package was delivered yesterday but won't be doing anywork on it till this weekend ler.. Need to go to JP to get the 'stuffs'!
I'll post the pre-work done pix first.. I have set my mind on this cute 'lil casing...

Y.C.,
You have to ask xtorm if there's going to be a second bulk for this. Maybe after this thread, there will be interested parties..

Good idea indeed!
A metal casing have it's advantages, shielding is one of them.
Hmm may I have one to spare

Terribly good question!
In this bolehland we do not have access locally to good casings..
we're limited to whatever that are being offered in the shops(JP), pricey, limited and pathetic designs.
If you can afford it, can be custom made but, definitely 'costly'.
Only you can justify the extra cost over a chip/'cheap' amp.

Agreed! The physical value may be 'small'; but the sonic value is 'awesome'.. hence, I will definite make an equally awesome casing!

Guys,
This just came to my mind.
The computer switching power supply typically have a +12V DC rated anything from 12A to 16A! I think this would be a great power supply to the T-Amp, no? I have read somewhere switching power supply works well with the T-Amp.
I think the casing is big enough to house the T-Amp entirely! Of course, a separate housing for the amp is another option.
Possible?

I finally got to open the package and assembled my T-Amp!
xtorm, your packing was excellent, thanx! Items arrived undamaged.

I have a 0-30VDC 3A bench power supply so powering the T-Amp is a cinch
Managed to listen for about 2 hours last nite!
Source was a SONY DVD Player connected to a YAMAHA pre-amp. Speakers are TDL's RTL3 Transmission Line speakers.
My speakers are rated 90dB at 1m for 1 watt.

This is my 2 hours of listening impression:

1. Upper frequencies from midrange and up; very accurate, vivid and detailed. I could picked up instruments so vividly. Vocals is the area where this T-Amp really shines, infact they are superb! I took out Diana Krall CD. She was singing and playing the piano right infront of me! In fact it made my reference amp sounds a bit 'smeared' in this department.
2. Low frequencies are all there: tight, but somewhat shy although well controlled. Probably due needing further burn in, the lower extension just wasn't there. Kick drums wasn't kicking enough, bass were generally without any 'weight'and 'attack'..I am a bass head and my speakers are definite bass heavy. I guess in a 'normal' setup, the T-amp may sound a 'lil bit bright.
3. Soundstage, depth and ambience were all there, solid and precise. All this from a 'RM55'?
4. I managed to add a 10uF cap to the existing input cap.. this somewhat improved the low end extension, need further listening and burn in!
5. I tested it and it handled from 21.5 Hz to 16kHz pretty well, just like my Technics! I did tried 20kHz, too bad, I just can't hear that high!

Initial conclusions:
1. For RM55 amp, this thing is hard to beat! This would be THE best Bang per Buck amp! Will give amps costings 100X over a run for the money!. I was comparing the T-Amp with my audiophile's Technics amplifier and a 40 W/ch DIY amp.
2. In it's stock configuration, very suitable for vocals and orchestral music, live recordings too! wow!
3. After 2 hours I can already detect improvements, so further listening and burn in is on the way! This is what weekend is for I guess
4. Will I sell off my Technics? Nope! There are reasons why it costs many many times over!
5. Since I have 2 boards, I may go into bi-amping...
6. Do we need 100W RMS/ch amp to drive a set of hifi speaker? Not if you're using this baby!

Sorry guys, no pics yet. Was terribly busy pulling out all my fav CDs..

This post has been edited by jazzy939: Aug 15 2008, 08:18 AM

xtorm,
the pleasure is mine! thank you for 'bulk'ing it

yes, the input caps does affect the sound. I did 'play' around with it last night. More experimentation to come!
you reckon 6600uF will do the trick? I may have to consider that too. I'll wait for your further input on this!
the output filter, what is your direction? I have in hand a few ferrite rings that was meant for some other project but was put on hold, I guess it's the time now to utilised it!
What values of inductance (uH) are we dealing with? I could make one, well two in this case for one board! Just furnish me with the values, ya? Refer attached pic if that is what you/we can use?
You sure this thing is useable in the car?
anyway, keep us posted with your mods ya? pics if possible.. I will too as soon as I am done playing around with the input caps and output filters.
I have to decide whether to use a linear PSU or switched mode. I also have a DIN55 battery at home. May use that to see any worthwhile sonic improvement running on a car battery!
I finally have the opportunity to test out my DIY preamp with T-Amp. Will do that this weekend.
Wait till you guys see the casing that I am saving for the completed integrated T-Amp...

Bro march,
WE brothers will not let any brother alone in the audio world!
Any plans for your T-Amp?

This post has been edited by jazzy939: Aug 15 2008, 11:08 AM


Attached thumbnail(s)

oh ya, four per board! price wise, no big deal!
ok, 10 uH. Will do that next.. hmm so much thing to ler !

If thats the case, will give smps a shot. i have a few computer's psu laying around.. 12V at 16A may do wonders!
BTW, I was running the PSU at 12.6VDC last nite. The TA2024 chip is just warm to the touch. I am impressed!



This post has been edited by jazzy939: Aug 15 2008, 11:24 AM

13.8? I might give that a shot!
yes.. while I was testing/experimenting with the input caps, I noticed a little hum when i got close to the input caps and the inductor area (output filter).. If we were to enclose the whole board and ground it, it will be much better?

This post has been edited by jazzy939: Aug 15 2008, 11:37 AM

Thanks Y.C. The pleasure is mine!
Experiencing the sonic performance is nothing like reading the reviews! Although 6moons and tnt-audio have a good write up, I was initially sceptical on the audio performance of the little 'thing'.. Hearing is believing, they say, now I know!

Yes, a lot has been mentioned on the caps, resistors and inductors alike.
As good as it is in it's stock configuration, what I like about this 'kit' is that there are still room for some 'tweaking' to further fine tune the audio to your liking.. A DIY enthusiast 'lil toy made in heaven..
Thank you for the link, will share/update my findings in this thread...


This post has been edited by jazzy939: Aug 15 2008, 02:34 PM

Wow.. you must have been a good salesman eh, selling items which you yourself don't have!!

I have NOT seen Neutrik RCAs in JP, they might have them but I never need them (yet). I normally got mine, a normal gold plated RCAs from NIXIE Electronics. I know one shop, at the end of the road after the traffic light heading towards Kg. Pandan. They have 'Neutrik' connectors there.. the one that I saw and bought was an audio jack for my headphones.. I'd say the best bet would be a 50K log pot.
As I am turning the T-Amp into a pure power amplifier, I have a separate preamplifier to drive it.

Btw, when will the stuffs be coming?


This post has been edited by jazzy939: Aug 15 2008, 04:12 PM

Thanks bro ong
It was a pleasure writing it as much as auditioning the little marvel..

My speakers have two 7 inch bass drivers per unit.
Initially, on my preamp, the volume setting was around 10 to 11 o'clock positions.. at the end of the two hour sessions, the level I need is just at 9 o'clock. Any higher, I think my neighbours might be knocking on my door! It's hard to believe that it can be that loud!

I'll make the coils first and see how it performs, then I make some to you guys. Noproblemo!

After much reading I have decided to go with a DC power supply using SLA or in my case, a DIN55 battery.
Have not done any sonic evaluation on this but I believe, the performance will be many times over a linear PSU. This is to the fact that there will be more than ample current from the battery to cater for transients requirement. No doubt, a linear PSU is able to do this but at a higher cost(better high quality circuits).
On top of that, it will be the cheapest way to power up the T-Amp...



This post has been edited by jazzy939: Aug 16 2008, 06:48 AM

Of course! How can I forget!
Bro March, still 'testing'? Long test eh?
Hey whats stopping you ler? Chassis/casing sudah ada...
But then again, looking at what you have.. I can live with that for quite awhile... long while even!
Hopefully mine can last that long also.. unless something (better and cheaper) comes up!


This post has been edited by jazzy939: Aug 16 2008, 10:31 AM

xtorm,
Its' Keep It Simple, Stupid or
Keep It Short (&) Sweet or
Keep It Sweet (&) Simple...
Take your pick. They all mean the same...

Your friend, lucky not water coming out from his eyes...

First pix here, showing the T-Amp on top of two 'massive' 10uF caps.. still process of burning in.
Playing Sean Ghazi's album SEMALAM make my hair stands on end...




Attached thumbnail(s)

I know but I kinda like what I hear now!
Let's see, the onboard caps (2 in parallel,) I measured to be 2uF plus my 10uF, total caps is now 12uF. Too much?

As the burn in process is progressing.. it gets closer and closer to my preference sound...

Will removed the the existing caps after I am satisfied that the burn in process no longer make any improvements.. See if there would be any/much difference..

This post has been edited by jazzy939: Aug 16 2008, 01:30 PM