Great!!!🙂
The master with his art. Thanks a lot Alex mm,
Just a minor change. use a trimmer in place of R12 for bias adjust or better split R12 into a 330R fixed resistor and a 500R trimmer in series.
Many thanks in advance.
Regards,
Aniket
I've seen your PM.
On the first pages of Bobs book it clearly states that no part of the publication shall be reproduced or distributed in any form or held or stored on data bases or retrieval systems without express written permission of the publisher.
For any book, and particularly one just in print, that should with all due respects be obvious to anyone.
Hello Alex mm.
There are some minor errors in the component values. and the emitter resistors R15, R18 and R16, R17 are missing for drivers(mje15032/33). Hope these are fixed in the next PCB revision.
Thanks and Regards,
Aniket
Quite frankly, I looked at the table of contents and skipped right on to Chapter 2.
Right or wrong, I thought I was already good enough to do that.
However, I think we're done with that subject, I was I believe quite clear about that.
"Throw away the MJE340/350s
Select transistors that suit VAS duty and pre-driver duty.
2n5551 are not good for the input LTP.
The bass roll-off frequency is unusually high.
Is this for Mid and Treble speakers only? "
Any suggestions, or just bilge?
The 2N5551 has been used as the LTP in many good amplifiers, as have the MJE340/350 as Vas.
His input pole is 12.5hz, feedback pole 2.65hz, power supply pole yet to be determined.
Select transistors that suit VAS duty and pre-driver duty.
2n5551 are not good for the input LTP.
The bass roll-off frequency is unusually high.
Is this for Mid and Treble speakers only? "
Any suggestions, or just bilge?
The 2N5551 has been used as the LTP in many good amplifiers, as have the MJE340/350 as Vas.
His input pole is 12.5hz, feedback pole 2.65hz, power supply pole yet to be determined.
In my view, 2N 5551/5401 are very fine transistors, only assuming they come from Philips or Motorola/ON Semi, which is not hard to do. I have used them quite a lot and will continue doing so.
I hasten to remind all that the source is not at all unimportant. While in general transistors of the same type will satisfy most if not all data sheet specs, there are differences in manufacturing technologies which will cause them to have subtle differences. Sometimes they are of no consequence, but other times, they may audibly impact the sound, if only in shades.
MJE 340/350, while quite outdated, are still a good choice in some cases, such as, for example, predrivers in three stage emitter-follower stages using older power transistors rated for 3 or 4 MHz responses. For one thing, they are very reliable and can be pushed quite hard without lasting consequences.
BC 546/556 B are also transistors which I would gladly recommend. While they are rated for 65V only, I have used them with as much as 58V power supply lines with no trouble at all. In my view, the best are those made by Siemens, Telefunken (part of the Siemens empire), Philips and Motorola/ON Semi.
Just my 2 cents' worth.
I hasten to remind all that the source is not at all unimportant. While in general transistors of the same type will satisfy most if not all data sheet specs, there are differences in manufacturing technologies which will cause them to have subtle differences. Sometimes they are of no consequence, but other times, they may audibly impact the sound, if only in shades.
MJE 340/350, while quite outdated, are still a good choice in some cases, such as, for example, predrivers in three stage emitter-follower stages using older power transistors rated for 3 or 4 MHz responses. For one thing, they are very reliable and can be pushed quite hard without lasting consequences.
BC 546/556 B are also transistors which I would gladly recommend. While they are rated for 65V only, I have used them with as much as 58V power supply lines with no trouble at all. In my view, the best are those made by Siemens, Telefunken (part of the Siemens empire), Philips and Motorola/ON Semi.
Just my 2 cents' worth.
Thanks Alex mm.
Please post the copper side and component side also. in pdf too.
Regards,
Aniket
PCB REV 1.1 ALL FILES
Hi,
...you have, attached below, all files ,you need ,to made this nice amplifier .😀
Was my pleasure to help again.....
Alex.
Hi,
...you have, attached below, all files ,you need ,to made this nice amplifier .😀
Was my pleasure to help again.....
Alex.
Bought the parts and got some PCB's manufactured. Now, would order a 42-0-42, 15A sec.(1250VA) transformer. Also, need a good airy chassis. Would start populating the boards and post the pics soon.
Regards,
Aniket
Regards,
Aniket
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