Dartzeel amp schematic - build this?

[VictoriaGuy]

Thanks!

 

[apoopoo999]

Other channel, on the other hand, has ~200mV DC, and the pot is already in its end position. Any suggestions?

Maybe your amp has poorly matched transitors. I bought my boards about a year ago and the seller (douk audio) stopped selling them. The kit came with matched components that were all labeled and packed in individual bags.

 

[adason]

I have already solved the problem by replacing few resistors

 

[ashok]

Adason: Does apoopoo999 and you have the same circuit and component values ?
Did apoopoo999 put up the circuit diagram of the unit he has ?
Thanks.

 

[adason]

I do not know, I do not have schematics of the kit from ebay, they refuse to provide that

 

[ashok]

Thanks. I wondered if they are all similar why should you have a problem.
Often they are just all copies . Tend to have similar parts.
The possibility is that the semiconductors are not matched in your unit....maybe !

 

[apoopoo999]

Here is the schematic that douk audio provided

An externally hosted image should be here but it was not working when we last tested it.

gifs upload

The boards I am using look like this

An externally hosted image should be here but it was not working when we last tested it.

free upload

 

[adason]

How do you adjust zero DC on the output?

 

[apoopoo999]

How do you adjust zero DC on the output?

There is a 50k pot for dc adjustment

The boards I have uses only one pair of mjl1302a/mjl3281a, 4 pairs of mje15032g/mje15033g and 2n551 and 2n5401.
I see the boards you have use 2 pairs of Toshiba 5200 and 1943

 

[adason]

Oh, I see the pot now...it looked like cap at first to me.

 

[sigius]

Have you compared its sound to gainclone? Comparison with SONY is the same as compare poop vs candy =D

 

[adason]

Have you?

 

[jlithen]

I have by the way compared mine to Aleph, Zen, F5, J2 et.c.
It was some time ago, I would say a bit brighter than pass amps and imaging might be close to all but Zen maybe...

My boards are the one with all big trannies in one row and only single output devices.

I will gladly sell this project to anyone who wants. Just boards or even all of it.
Need to put time, money and enclosure on the VFET amp now
A photo can be found on the first page of this thread.

 

[cl00sed]

Planning to with the updated board, did some one tried out?
If so please let me know so that it would help me.

Out put power is stated as 100W @ 8ohms in one site and for the same mentioned as 140W @8 ohms, which one is correct and how to achieve 140w @8ohms with same board what is the recommended DC input voltage?
Best Regards

 

[gaborbela]

You can buy that damned think - no need for DIY
DARTZEEL NHB-18NS PREAMPLIFIER WITH NHB-108B POWER AMPLIFIER (INC MC PHONOSTAGE) | eBay

 

[chrisng]

what is the recommended DC input voltage?

Douk Audio Non-NFB Amplifying Circuit 150W 2.0 Channel Power Amplifier DIY Kit | eBay

dual 35-40vac 300-500w transformer

You can buy that damned think - no need for DIY

or the one that they do it for you:

Douk Audio Professional Hi-End Non-NFB Power Amplifier Stereo HiFi Amp 250W@4ohm

 

[cl00sed]

Thanks for the info, the board which i shared is an updated board than the above
Want to know if some one had tried the new version

 

[apoopoo999]

I have both the Douk audio and the V0.2 boards from aliexpress.
They are both exactly the same

 

[cl00sed]

I have both the Douk audio and the V0.2 boards from aliexpress.
They are both exactly the same

Both exactly same in case of performance or the design?

 

[danny_66]

There's now also a DC servo

If using the DC servo you can remove the input caps and the DC trimmer,
the amp becomes then DC coupled.
The SNCP cap is also not needed anymore, that's the single cap in the middle.