Carlos,
Just saw that my output transistor stock gone out.
Did a lot of repairs this week on self-powered PA speakers and now I'm looking for what is the best output transistors that I can put on the DX AMP.
I know, you will say: GO SANKEN. I wish I could have them here to put on my stereo build, but they are hard to find (as you must know, I live in Brazil as you too) and my principal supply of Output transistors are Farnell-Newark.
So, What do you reccomend?
And many thanks by sharing this amplifier with us, a beautiful sonics amplifier.
Just saw that my output transistor stock gone out.
Did a lot of repairs this week on self-powered PA speakers and now I'm looking for what is the best output transistors that I can put on the DX AMP.
I know, you will say: GO SANKEN. I wish I could have them here to put on my stereo build, but they are hard to find (as you must know, I live in Brazil as you too) and my principal supply of Output transistors are Farnell-Newark.
So, What do you reccomend?
And many thanks by sharing this amplifier with us, a beautiful sonics amplifier.
Much better than to search for a replacement transistor
I suggest you to try to figure out the reasons you have lost power transistors...you know..this never happened before....hundreds have built...i also have build hundreds.... this does not happens when the amplifier is well assembled, well adjusted and not submited to misuse.
So, something is wrong in your amplifier.... wrong current, wrong insulator, no good size to heatsink, strange speaker crossover network producing spikes and back EMF.... short in the output...too much low output impedance.. mistaken bias settings...well...there's a lot of things you should check...AC in the output (oscilations)...the compensation capacitor value..
One thing is clear...you belong to exception as no one have faced so many troubles with this amplifier....it is the second or third time you report problems....maybe misuse.
What about to try something more simple..... give a try on the P3A...it is a nice amplifier and probably will fit your needs...also you can study a lot of replacement transistors for it.
I was thinking...maybe you should continue with Radio Frequency repairs, as far as i know you are very good in RF.
regards,
Carlos
I suggest you to try to figure out the reasons you have lost power transistors...you know..this never happened before....hundreds have built...i also have build hundreds.... this does not happens when the amplifier is well assembled, well adjusted and not submited to misuse.
So, something is wrong in your amplifier.... wrong current, wrong insulator, no good size to heatsink, strange speaker crossover network producing spikes and back EMF.... short in the output...too much low output impedance.. mistaken bias settings...well...there's a lot of things you should check...AC in the output (oscilations)...the compensation capacitor value..
One thing is clear...you belong to exception as no one have faced so many troubles with this amplifier....it is the second or third time you report problems....maybe misuse.
What about to try something more simple..... give a try on the P3A...it is a nice amplifier and probably will fit your needs...also you can study a lot of replacement transistors for it.
I was thinking...maybe you should continue with Radio Frequency repairs, as far as i know you are very good in RF.
regards,
Carlos
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Carlos,
Didn't lost power transistors any time with DX Amp, just used my MJL3281 and 1302 stock to repair a bunch of amplifiers from friends/clients and now I'm trying to figure what to buy to use on the output stage.
I have built around 8~10 DX Blame ST's and just one didn't worked out in the first test because I MADE some problems to the pcb while making it.
DX Amps showed to be a amp that even if you never did it before you can go there and make and excellent amplifier and if you have experience and equipment you can do it better.
Just wanna know what do you recommend for using as output device as I can't buy 2sc5200/2sa1943 and MJL3201/MJL1302 from Farnell anymore =(
I'm going to make a 4 channel DX Blame ST for my bi-amp tower system.
Regards Mr Carlos,
Felipe
Didn't lost power transistors any time with DX Amp, just used my MJL3281 and 1302 stock to repair a bunch of amplifiers from friends/clients and now I'm trying to figure what to buy to use on the output stage.
I have built around 8~10 DX Blame ST's and just one didn't worked out in the first test because I MADE some problems to the pcb while making it.
DX Amps showed to be a amp that even if you never did it before you can go there and make and excellent amplifier and if you have experience and equipment you can do it better.
Just wanna know what do you recommend for using as output device as I can't buy 2sc5200/2sa1943 and MJL3201/MJL1302 from Farnell anymore =(
I'm going to make a 4 channel DX Blame ST for my bi-amp tower system.
Regards Mr Carlos,
Felipe
Any power transistor able to face 100 volts or more from colector to emitter will fit
Also you need power transistors that can hold 5 amperes of current or more.
If not fake ones you will not face any trouble with output transistors, unless misuse, small heatsink, shorts in the output, reactive loads, too much low impedance or injecting full power square waves that generates harmonics and also drive transistor to full conduction of the supply current.
Only errors will damage your amplifier.... if operate correctly with the suggested supply voltage and suggested speaker impedance you will not experience failures as this unit was deeply tested and tortured along several years...and i could not destroy output transistors...so, the amplifier is very safe and reliable... doing correct things you can select any power transistor you find, modern or or old ones...metalic or plastic case..... naturally your choice cannot be fake units... or shorted parts or components with leakage or something wrong.
Also, i have to say, no one reported failure or damage....you are the only one that has faced problems..... reason why i figure out you made mistakes or your transistor was fake.
Carlos
Also you need power transistors that can hold 5 amperes of current or more.
If not fake ones you will not face any trouble with output transistors, unless misuse, small heatsink, shorts in the output, reactive loads, too much low impedance or injecting full power square waves that generates harmonics and also drive transistor to full conduction of the supply current.
Only errors will damage your amplifier.... if operate correctly with the suggested supply voltage and suggested speaker impedance you will not experience failures as this unit was deeply tested and tortured along several years...and i could not destroy output transistors...so, the amplifier is very safe and reliable... doing correct things you can select any power transistor you find, modern or or old ones...metalic or plastic case..... naturally your choice cannot be fake units... or shorted parts or components with leakage or something wrong.
Also, i have to say, no one reported failure or damage....you are the only one that has faced problems..... reason why i figure out you made mistakes or your transistor was fake.
Carlos
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trying Baffle Step Compensation woofer 1.7ohm paralel 0.4mh to suppres upper midrange frequency.
sweet... low vocal freq more clearer. but low freq increase to 🙁
my mistake forgot to add zobel...
sweet... low vocal freq more clearer. but low freq increase to 🙁
my mistake forgot to add zobel...
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First, you might consider adding to your list of options the Fairchild FJL4215 and 4315.
I think Fairchild actually sells the C5200 as well.
Next, Below are the Brazilian distributors that are listed on Fairchild's website.
Some of them also sell the other brands such as Sanken and On Semi.
Karimex
Rua Americo Brasiliense 2444
Sao Paulo, 04715-005
Tel: 55 1151891900
Fax: 55 1151819380
Arrow Electronics
Rua José Gomes Falcão
111 - CEP 01139-010
São Paulo - SP - Brasil
Tel: 55 11 3613-9300
Fax: 55 11 3613-9355
Avnet
Rua Luis Gois 1205 - 2o Andar
Sao Paulo, 04043-300
Tel: 5511-5079-2150
Future Electronics
Rua Ernesto da Fontoura,
1479/607
Bairro São Geraldo
Porto Alegre
Rio Grande do Sul
90230-091
Tel: +55 51 4009 4900
Fax: +55 51 3325 1568
Rua Luzitana,
740, 10 Andar,
Conjuntos 103/104, Centro
Campinas
São Paulo
13015-121
Tel: +55 19 3737 4100
Fax: + 55 19 3236 9834
Next, both Faichild and On Semiconductor can be purchased directly from their website.
With On semi you are required to buy a minimum of 25 devices. But it appears you would
use them anyway.
Hope this helps.
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The problem is, mod_evil is looking for obsolete parts - he can't buy them from Farnell-Newark because the have been superseded. 😉
From the original sources.......
Look for TTC5200/TTA1493 (TO264) or 2SC5200N/2SA1943N (TO3P) [Toshiba]
Look for MJL4281/MJL4302 [ON Semi]
Otherwise, as Glen 65 suggests, there are plenty of competitor suppliers and products in every country the size of Brasil and even much smaller.
From the original sources.......
Look for TTC5200/TTA1493 (TO264) or 2SC5200N/2SA1943N (TO3P) [Toshiba]
Look for MJL4281/MJL4302 [ON Semi]
Otherwise, as Glen 65 suggests, there are plenty of competitor suppliers and products in every country the size of Brasil and even much smaller.
FJL4215/4315 is a very good pair of transistors
I have them and i am using them...very happy with them.... satisfied and a lot!
Bagus?..... nice idea...can you produce video to show us the effect dear bagus...and more details please...in series with the full range driver?
regards,
Carlos
I have them and i am using them...very happy with them.... satisfied and a lot!
Bagus?..... nice idea...can you produce video to show us the effect dear bagus...and more details please...in series with the full range driver?
regards,
Carlos
http://diyaudioprojects.com/Speaker...p-Compensation-Circuit-Fostex-FE206En-DBR.png
the pict from diy audio web. try your own number uncle. you can simulated with blode ploter in multisim. and ithink 1ohm paralel wit 0.4mh is perfect (if i'm not wrong 😀 )
the pict from diy audio web. try your own number uncle. you can simulated with blode ploter in multisim. and ithink 1ohm paralel wit 0.4mh is perfect (if i'm not wrong 😀 )
Thank you dear Bagus...very kind from you.
I have not watched the video...gonna do it latter on...now too much busy.
But there's something i want to say.
What makes and what made this amplifier so interesting to the builders was that effect (can considered defect too) related the loosen, longer bass tones reproduction... this was the main point that attracted so many folks to build..also because the amplifier is simple, cheap to build and small in size.
If we do something to fix, or to change the sonic signature, we gonna be betraying the ones where attracted to this unit.... reason why i do not support any modification on it.
That longer, not precise, interesting, deep and mufled bass is the cherry of the cake.
- "tones that stir the viscera, the bowels of the listener"
regards,
Carlos
I have not watched the video...gonna do it latter on...now too much busy.
But there's something i want to say.
What makes and what made this amplifier so interesting to the builders was that effect (can considered defect too) related the loosen, longer bass tones reproduction... this was the main point that attracted so many folks to build..also because the amplifier is simple, cheap to build and small in size.
If we do something to fix, or to change the sonic signature, we gonna be betraying the ones where attracted to this unit.... reason why i do not support any modification on it.
That longer, not precise, interesting, deep and mufled bass is the cherry of the cake.
- "tones that stir the viscera, the bowels of the listener"
regards,
Carlos
Attachments
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This was a variation of the Dx Amplifier we were preparing to release
*Post edited by Moderator at OP's request.*
See the pcboard size comparing to the power transistors.
regards,
Carlos
*Post edited by Moderator at OP's request.*
See the pcboard size comparing to the power transistors.
regards,
Carlos
Attachments
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Dear friends, uncle charlie is alive and healthy
Now a days not building stuff or creating amplifiers...just following news from Televison and Internet about Politics in Brazil...we are living a mess here... a danger and big risk to become a Comunist country...a huge problem.
A big hug to all of you.
regards,
Carlos
Now a days not building stuff or creating amplifiers...just following news from Televison and Internet about Politics in Brazil...we are living a mess here... a danger and big risk to become a Comunist country...a huge problem.
A big hug to all of you.
regards,
Carlos
Attachments
Looking slim and healthy Carlos.
Thanks for the help over the years and if Brazil gets too bad there is always a bed for you here. You will need a warm hat though.
John
Thanks for the help over the years and if Brazil gets too bad there is always a bed for you here. You will need a warm hat though.
John
Thanks a lot John...i am still thinking to get the hell out of here
Because in 6 months maybe gonna be too late.
regards,
Carlos
Because in 6 months maybe gonna be too late.
regards,
Carlos
Carlos,
I'm very sorry to hear about the issues in your country. The world is preparing for a nasty recession I feel......
I was not aware that Nordic died? This is terribly sad, how old was he? Was this illness, or accident?
He did some wonderful work here, I remember him clearly - like I remember you, Carlos, you will never be forgotten either.......
Ciao,
Hugh
I'm very sorry to hear about the issues in your country. The world is preparing for a nasty recession I feel......
I was not aware that Nordic died? This is terribly sad, how old was he? Was this illness, or accident?
He did some wonderful work here, I remember him clearly - like I remember you, Carlos, you will never be forgotten either.......
Ciao,
Hugh
Carlos, I really understand what you mean... 🙁
Things don't develop well here also. I'm actually preparing for relocation to Europe.
Hope, Brasil will go the right direction in the end (not the communist one).
Cheers,
Valery
Uncle Charlie, nice to see you again. Just a gentle reminder that we avoid political discussions here but if there is more to say, invite someone to speak with you offline.
Thanks for your understanding as always.
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