Yes, because I may be wrong! And since I have not money enough to try both, I have two choose beetwen one or the other topology. I am back to solid state after more than 25 years of tube. I had a Bryston and A Mark Levinson in the past. Bipolar was the reference at this time. I must admit that I never had a mos amplifier. I would rather go to mos because the technology progressed and the market seems to be here now. As soon as we are talking about the 30-800Hz range only with 15'' speakers I have no reference to compare and decide. I would appreciate a discussion regarding this topic!
Hello
The Nelson Pass mosfet Citation 12 amp sound better than the original version.
You can find answers in those two thread;
http://www.diyaudio.com/forums/pass-labs/83434-citation-12-mos-fet.html
http://www.diyaudio.com/forums/pass-labs/107385-citation-12-questions.html
Bye
Gaetan
The good point also is that I could reuse everything incl. the PCB with the exception of all the transistors. I spent two days trying to find the transistors or equivalent with no success. Just find 1 type in Ireland, one or 2 in USA, maybe one in France and one in Hong Kong!!!
If I was sure I can get the all good stuff at the same place I would not hesitate a second. The dX is fore sure a superb circuit and I will build it if I cannot find the parts that fit with the HK boards.
Thanks,
Yes...i love this music too..... well Jeepy, i think so..but to be
sure, go to greg home pages and observe the boards width and length ... i am not sure if the Blame will fit...maybe the Dx Amplifier, the standard one, this thread amplifier.
You will assemble layed down, alike someone sleeping over a bed..one side down..one arm to the matress....so...the width is the measurement you should check...maybe too big and the board should be higher than the heatsing and the cover may hit it.
Another way is to assemble the other side..and run wires to power transistor througth holes... this may be very good, as you will have the chassis bottom as ground plane... wires to transistors, if not bigger than 12 centimeters should not be a problem... you can twist them together...and the result will be fine.... maybe 2pf capacitors this way...the wire may represent these capacitors...not twisting creating a cable, then the capacitance reduces in such ammount will not bother you..... even inductance is small to bother...the output has not too much sensitivity...the gain there is around 50.
regards,
Carlos
sure, go to greg home pages and observe the boards width and length ... i am not sure if the Blame will fit...maybe the Dx Amplifier, the standard one, this thread amplifier.
You will assemble layed down, alike someone sleeping over a bed..one side down..one arm to the matress....so...the width is the measurement you should check...maybe too big and the board should be higher than the heatsing and the cover may hit it.
Another way is to assemble the other side..and run wires to power transistor througth holes... this may be very good, as you will have the chassis bottom as ground plane... wires to transistors, if not bigger than 12 centimeters should not be a problem... you can twist them together...and the result will be fine.... maybe 2pf capacitors this way...the wire may represent these capacitors...not twisting creating a cable, then the capacitance reduces in such ammount will not bother you..... even inductance is small to bother...the output has not too much sensitivity...the gain there is around 50.
regards,
Carlos
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Yes it will work. There is plenty of room!
http://img532.imageshack.us/img532/3110/image3hz.png
It will also benefit of the full dual mono configuration. I will post when finished and tested. Many thanks!
Yes.... dual mono will give you advantage in power, also separation, lower distortion
because left channel current drain will not modulate the rigth channel amplifier.. sound stage will be perceived as better...more clear, more defined....more focused.... and less deep
Good.... result will be excelent...install input volume if you have not and go ahead..plug your CD player, or DVD player or DAC directly in the power amplifier input..avoid pre amplifiers and you will have, also, an advantage in sonics compared to others.
regards,
Carlos
because left channel current drain will not modulate the rigth channel amplifier.. sound stage will be perceived as better...more clear, more defined....more focused.... and less deep
Good.... result will be excelent...install input volume if you have not and go ahead..plug your CD player, or DVD player or DAC directly in the power amplifier input..avoid pre amplifiers and you will have, also, an advantage in sonics compared to others.
regards,
Carlos
Yes! One more question, Carlos before I order the components. We can see huge capacitor value in the PSU sometimes. Since I have to change mines is there any benefit to increase those a bit? Also I suppose that fast recovery rectifiers would be better than the bridges in place, right?
I do not think so...some advantage is more psychological then real
You can try more condensers in your supply... the amplifier will work happy with 12.500uf each rail...or more than that, to each power amplifier.
So, total, should be 50.000uf to the stereo, when sending 100 plus 100 watts rms to 4 ohms speakers.
If you decide to use 8 ohms, half of that will be good..divide by two everything i wrote above.
What i mean about psychological effect (this does not dennie that exists some real effect too..but small) ... means if you believe...and not use...then you will always thinking the amplifier could, or should, reproduce better audio IF you have used the "golden" parts...audiophile grade..super high speed... black stripped, snake oil dampened, super duper doooooo parts!.... if you are a believer..and these things have not connection to science..is more religion..then substitute everything by Ziclon Dablon Teflon parts...if you are not a believer.... find some junk, remove cocaroach and spiders and go ahead because sound will not sound alike cocaroach or spider.
It is up to you man!
Full ship!..... i mean... a ship filled with those special parts may arrive soon at your town.
ahahahahah!
regards,
Carlos
You can try more condensers in your supply... the amplifier will work happy with 12.500uf each rail...or more than that, to each power amplifier.
So, total, should be 50.000uf to the stereo, when sending 100 plus 100 watts rms to 4 ohms speakers.
If you decide to use 8 ohms, half of that will be good..divide by two everything i wrote above.
What i mean about psychological effect (this does not dennie that exists some real effect too..but small) ... means if you believe...and not use...then you will always thinking the amplifier could, or should, reproduce better audio IF you have used the "golden" parts...audiophile grade..super high speed... black stripped, snake oil dampened, super duper doooooo parts!.... if you are a believer..and these things have not connection to science..is more religion..then substitute everything by Ziclon Dablon Teflon parts...if you are not a believer.... find some junk, remove cocaroach and spiders and go ahead because sound will not sound alike cocaroach or spider.
It is up to you man!
Full ship!..... i mean... a ship filled with those special parts may arrive soon at your town.
ahahahahah!
regards,
Carlos
Here you may find informations about Dx amplifiers, schematics and layouts
Greg's Web Site
regards,
Carlos
Greg's Web Site
regards,
Carlos
My DX has played for the first time tonight and I'm a happy camper.
I had some problems with one channel giving high DC offset with the lightbulb tester remaining lit when I first powered it up to test.
I took the pcbs off the heatsink and inspected them again. It took a lot of searching to find the problem, I had left one wire on my bias board unsoldered despite checking it a couple of times. I didn't check well enough obviously. Once that was corrected both channels are fine and ready for the bias and offset adjusting.
I couldn't resist a quick listen using my old 3 inch test speakers and a "no name" cheap mp3 player headphone socket as source. First impressions of the sound are very pleasing indeed considering nothing is adjusted yet.
A few photos are here.
DX Amplifier pictures by Jblackburn_photos - Photobucket
Thanks to Carlos for the design, help and being an all round good bloke. This is the biggest project I have taken on, it was good to have someone to explain things in a way understandable to the non expert. It made the step from chip amps to a discrete build much easier for me.
Also thanks to AndrewT for telling me about the lightbulb tester in the first place. If I hadn't had the visual indication that the current draw was remaining high, I would have found out there was a fault when the magic smoke came out.
John
I had some problems with one channel giving high DC offset with the lightbulb tester remaining lit when I first powered it up to test.
I took the pcbs off the heatsink and inspected them again. It took a lot of searching to find the problem, I had left one wire on my bias board unsoldered despite checking it a couple of times. I didn't check well enough obviously. Once that was corrected both channels are fine and ready for the bias and offset adjusting.
I couldn't resist a quick listen using my old 3 inch test speakers and a "no name" cheap mp3 player headphone socket as source. First impressions of the sound are very pleasing indeed considering nothing is adjusted yet.
A few photos are here.
DX Amplifier pictures by Jblackburn_photos - Photobucket
Thanks to Carlos for the design, help and being an all round good bloke. This is the biggest project I have taken on, it was good to have someone to explain things in a way understandable to the non expert. It made the step from chip amps to a discrete build much easier for me.
Also thanks to AndrewT for telling me about the lightbulb tester in the first place. If I hadn't had the visual indication that the current draw was remaining high, I would have found out there was a fault when the magic smoke came out.
John
Dx amplifiers plays music with awsome quality
And do that without losses.
YouTube - Dx Blame, awsome sonics!
regards,
Carlos
And do that without losses.
YouTube - Dx Blame, awsome sonics!
regards,
Carlos
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