I see...... i do not know...this depends on Zimmer
I do not run group buys as you know..... i do no like the activity and also i do not want to put my hand on money...it is better to be out of that...you know what i mean.
Mitchel is not available...he will start to work at Petrobrás soon....if Zimmer want to run then no problems to me...he can do it.
regards,
Carlos
I do not run group buys as you know..... i do no like the activity and also i do not want to put my hand on money...it is better to be out of that...you know what i mean.
Mitchel is not available...he will start to work at Petrobrás soon....if Zimmer want to run then no problems to me...he can do it.
regards,
Carlos
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I am glad to inform , the pcboards Zimmer is offering are the Blue boards
From The MKII Supercharged.
Orders are directly with him....heis 3 thousand kilometers South related my place if you want to know...he is in the South of Brasil. living in one of our German towns
His email:
imap.eletro@gmail.com
Here you have a video about German towns in Brazil:
http://www.youtube.com/watch?v=ASrUNevw76g
regards,
Carlos
From The MKII Supercharged.
Orders are directly with him....heis 3 thousand kilometers South related my place if you want to know...he is in the South of Brasil. living in one of our German towns
His email:
imap.eletro@gmail.com
Here you have a video about German towns in Brazil:
http://www.youtube.com/watch?v=ASrUNevw76g
regards,
Carlos
Zimmer, form Brazil, said he can provide you cheap multimodel blue boards
The Supercharged blue boards will cost 7 USD each one.....naturally you have shipment to include.... Zimmer said he has paypall.
I do not accept orders.... Zimmer is the one is receiving orders.... go directly and straight to Zimmer.
Boards are good to assemble four different models, including Dx Blame ST....you can see details here:
http://www.nabucoeletronica.com.br/dx/home.html
Zimmer email:
imap.eletro@gmail.com
regards,
Carlos
The Supercharged blue boards will cost 7 USD each one.....naturally you have shipment to include.... Zimmer said he has paypall.
I do not accept orders.... Zimmer is the one is receiving orders.... go directly and straight to Zimmer.
Boards are good to assemble four different models, including Dx Blame ST....you can see details here:
http://www.nabucoeletronica.com.br/dx/home.html
Zimmer email:
imap.eletro@gmail.com
regards,
Carlos
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I have found that BC546/556 results better in sonics
It seems to me they are more linear to be used in audio amplifiers powered with 35 volts supplies.
I do suggest you to try, but be aware that some boards where made for 2N5401/5551 (Supercharger blue boards) and the transistor lead identification is different.... to install a different transistor, or switch from 2N to BC transistor you should twist 180 degrées related the silk screen reference drawing.
See the image and be carefull about that....i am sure you will like the result..but this should be made only with 35 volts supplies (Dx Blame ES and Dx Blame ST and MKII (low impedance one that uses 35 volts)).
Thank you Vargas Mongo, as you provided the image for us.
regards,
Carlos
It seems to me they are more linear to be used in audio amplifiers powered with 35 volts supplies.
I do suggest you to try, but be aware that some boards where made for 2N5401/5551 (Supercharger blue boards) and the transistor lead identification is different.... to install a different transistor, or switch from 2N to BC transistor you should twist 180 degrées related the silk screen reference drawing.
See the image and be carefull about that....i am sure you will like the result..but this should be made only with 35 volts supplies (Dx Blame ES and Dx Blame ST and MKII (low impedance one that uses 35 volts)).
Thank you Vargas Mongo, as you provided the image for us.
regards,
Carlos
Attachments
Might want to use the BC550C/560C pair, they're the low-noise variant of the 55x/56x series, they have a Vceo of 30V if I remember correctly, which you can reduce by applying a series zener to help dissipate and get Vce voltage in a suitable range. The 546/556 are the higher Vceo variants at cost of a bit more noise.
More noise maybe only on paper. I am sure your ears would never pick up. I would recommend building dx's amplifiers exactly as is shown on his schematics. Carlos is famous for producing the best bang for the buck amplifiers out there. Using readilly available components you may have lying around such as the bc556. I am certain the results will blow away many more higher cost amps which house boutique components inside them. You can all go buying hugely expensive and hard to procure caps, resistors and transisters etc but you will be the one embarrassed at having to spend more money then average Joe next door whose amplifier will sound the same to "human" ears.
I have found that BC546/556 results better in sonics
Sonics is what Carlos's amps are about. Please build and find out.
Regards
Simon
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Thanks a lot by your support dear Simon
I could not try BC547/557..... i do imagine that, electrically, it may be even better, i do not know about sonics.
Also i have found that BD139 and BD140 are unbeatable to VAS and Drivers when the amplifier operates from 30 to 40 volts supplies..... alike everybody i do think i am fooling myself when i perceive that..then i do comparison and usually confirm they are better...... to 35 volts, aproximatelly, these ones sounds better.
I have tried 2N5401/5551.... also other models, some high speed devices... some MPS too....i have tried 2SC1815 and it's complementary in matched pairs...no way to beat BC546/556 into the Dx Blame ES and Dx Blame ST and also into the Dx amplifier and all models using 35 plus 35 volts supplies.... i do imagine they are more linear to that voltage.... matched perfectly to the circuit currents and operates great offering more sonic transparency, more dinamics, more high end, but noise is a little bit higher.... well.... have to put your ears against the tweeter to listen...so...higher or not higher will not bother us anyway.
For the drivers position, also second VAS transistor, i have tried several transistors, MJE340/350 was not good, also addicted to oscilate with the capacitor values used in the compensation.... i have tried 2SC4793/2SA1837 but i found it poor in dinamics.... also poor in treble, also i have tried other transistors, some power units in the driver's position and some old driver pairs that where famous a decade ago.... and no way to beat BD139/140.
I was always surprised with Gradiente, a big audio company we had from the sixties to the 1991.... despite they imported the best power output transistors (some old big rectangular Toshibas) they used the BD139/140.... i was astonished, because ugly ones, small ones, different colour for the NPN to the PNP, that awfull back metalic part (not regular the shape is confused)...now a days i understand clearly..... reason is sonics...to 35 volts amplifiers i could not find another one with better sound.
I have compared all i have here.... 5 amplifiers, all them different in models, pcboards and transistor used..... the unit using these transistors (BC546/556 - BD139/140) has beated others clearly and without any doubt.
I have called wife, the maid, my daugther and a neighboor to evaluate.... they agreed.... the test was blind...amplifiers with panel pointed the wall (not to see meters moving, not to identify the amplifier was playing)..same power...same audio source...same volume and same speaker...i was switching speaker only...... can this be different with another speaker?....maybe...i am not sure about...i do think will confirm...but i am not sure about it.
Amplifiers in test:
Dx Blame ES - Blue board from Brazilian and also International group buy
Dx Blame ST - Blue board from Brazilian group and also International group buy
Dx Blame MKII - Blue board from Brazilian group and also International group buy
Dx Blame MKII Supercharged - Blue board from Brazilian group and also International group buy
Dx Blame ST using green pcboard made by Mitchel (Brazilian group buy)
Dx Blame ST using Todd Johnson pcboard (first one made)
The winner is this one above.... now i will inspect if some resistor is different and the capacitor brands used and values that are not the same suggested in the schematic...trying to find other reasons than the transistor itself.
regards,
Carlos
I could not try BC547/557..... i do imagine that, electrically, it may be even better, i do not know about sonics.
Also i have found that BD139 and BD140 are unbeatable to VAS and Drivers when the amplifier operates from 30 to 40 volts supplies..... alike everybody i do think i am fooling myself when i perceive that..then i do comparison and usually confirm they are better...... to 35 volts, aproximatelly, these ones sounds better.
I have tried 2N5401/5551.... also other models, some high speed devices... some MPS too....i have tried 2SC1815 and it's complementary in matched pairs...no way to beat BC546/556 into the Dx Blame ES and Dx Blame ST and also into the Dx amplifier and all models using 35 plus 35 volts supplies.... i do imagine they are more linear to that voltage.... matched perfectly to the circuit currents and operates great offering more sonic transparency, more dinamics, more high end, but noise is a little bit higher.... well.... have to put your ears against the tweeter to listen...so...higher or not higher will not bother us anyway.
For the drivers position, also second VAS transistor, i have tried several transistors, MJE340/350 was not good, also addicted to oscilate with the capacitor values used in the compensation.... i have tried 2SC4793/2SA1837 but i found it poor in dinamics.... also poor in treble, also i have tried other transistors, some power units in the driver's position and some old driver pairs that where famous a decade ago.... and no way to beat BD139/140.
I was always surprised with Gradiente, a big audio company we had from the sixties to the 1991.... despite they imported the best power output transistors (some old big rectangular Toshibas) they used the BD139/140.... i was astonished, because ugly ones, small ones, different colour for the NPN to the PNP, that awfull back metalic part (not regular the shape is confused)...now a days i understand clearly..... reason is sonics...to 35 volts amplifiers i could not find another one with better sound.
I have compared all i have here.... 5 amplifiers, all them different in models, pcboards and transistor used..... the unit using these transistors (BC546/556 - BD139/140) has beated others clearly and without any doubt.
I have called wife, the maid, my daugther and a neighboor to evaluate.... they agreed.... the test was blind...amplifiers with panel pointed the wall (not to see meters moving, not to identify the amplifier was playing)..same power...same audio source...same volume and same speaker...i was switching speaker only...... can this be different with another speaker?....maybe...i am not sure about...i do think will confirm...but i am not sure about it.
Amplifiers in test:
Dx Blame ES - Blue board from Brazilian and also International group buy
Dx Blame ST - Blue board from Brazilian group and also International group buy
Dx Blame MKII - Blue board from Brazilian group and also International group buy
Dx Blame MKII Supercharged - Blue board from Brazilian group and also International group buy
Dx Blame ST using green pcboard made by Mitchel (Brazilian group buy)
Dx Blame ST using Todd Johnson pcboard (first one made)
The winner is this one above.... now i will inspect if some resistor is different and the capacitor brands used and values that are not the same suggested in the schematic...trying to find other reasons than the transistor itself.
regards,
Carlos
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The sound differences experienced between components is easily explained,, it has nothing to do with magic, religion or transistor physics. It has all to do with engineering decisions. Carlos you miss the point a bit by stating they are more linear, this is not neccesarily so, here its a simple matter of correct or ideal part for the application.
Ive already explained the theory regarding the LTP transistors in another thread. See here http://www.diyaudio.com/forums/solid-state/206801-hfe-question-2.html
Posts 11, 15 ,19 ,20, thats the reason the BCs are better that the 2n devices (this applies to LTPs only) and you can read the sound improvements the builder experienced if you read the rest of the thread.
As for the BDs the main reason they work so well is again easily explained according to theory. They are fast, very fast for a part that can handle the current they can. As drivers they excel as they have very low Cob and Ceb capacitances. These parts are basically BC639 TO92 parts put in bigger package for higher dissipation, take a look at that datasheet and you get all the info the BD datasheets lack. Carlos is right about using the BDs as drivers, they might be long in the tooth but long live the BDs.
In the vas position they are also no slouch for the reasons already explained although here you could do better with specialized video transistor parts like 2sa1360, 2sa1380 ect.
Ive already explained the theory regarding the LTP transistors in another thread. See here http://www.diyaudio.com/forums/solid-state/206801-hfe-question-2.html
Posts 11, 15 ,19 ,20, thats the reason the BCs are better that the 2n devices (this applies to LTPs only) and you can read the sound improvements the builder experienced if you read the rest of the thread.
As for the BDs the main reason they work so well is again easily explained according to theory. They are fast, very fast for a part that can handle the current they can. As drivers they excel as they have very low Cob and Ceb capacitances. These parts are basically BC639 TO92 parts put in bigger package for higher dissipation, take a look at that datasheet and you get all the info the BD datasheets lack. Carlos is right about using the BDs as drivers, they might be long in the tooth but long live the BDs.
In the vas position they are also no slouch for the reasons already explained although here you could do better with specialized video transistor parts like 2sa1360, 2sa1380 ect.
Chill friend
It was just a suggestion that might help him get even better sonics. That I like wires with gain does not mean that I disrepect other people's design phylosophies..
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