Explendid amplifier designed by Michael Bittner, our MikeB

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#1,843
tttking said:
Hi Sheldon:

Since you had really good result in matching transistors, I decided to match my transistors using your simplified method. Would you please tell me what % of voltage difference you considered acceptable when you did it? Is 0.4 % too large?
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Most of the base to emitter voltages were around 500 - 700mV. I was able to get pairsmatched to within a mV or so. The measurements seemed reasonably repeatable.

Sheldon
 
#1,844
MikeB said:
Hi Terry, the wiring is correct, i was only confused by some wires, it might be the limited visibility on photos. I marked the ones i mean.

Mike
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Hi Mike,

I'm sorry but the pics are misleading. The things you circled are actually string. The speaker cable has a nylon string along side the wires to add strength when pulling the cable through conduit. You are seeing the tag ends of the string. I should have just pulled that piece of string out. :cannotbe:

jmateus said:
Great job Terry, it looks like the initial mishaps paid off and were
only a small snag... Good

And I thought mine were ok, nah....
At first the steel looked a bit odd but after a while the overaul
aspect of the cabinet seems to make sense.

I also noticied the wiring being in the wrong place....

Congratulations, a job well done.
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That diamond plate is actually made of aluminum, not steel. 😀

dtrif said:
Terry congratulations for your casing, really very nice work on the most difficult part of such contructions: mechanical work!
I am a fan of completely seperate PSU's for each channel also. But I can't also confirm a difference in sound, since all my constructions (of power amps) have always been with seperate PSU's. So , I haven't done a comparison.
Regards,
Dimitris.
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I still have the 5_2 boards mounted on a couple of heatsinks. I also have 3 more transformers so I will try hooking them up with seperate PSU's and run them side by side with the 5_3 I just finished. I'll report back when I have done it.

Blessings, Terry
 
#1,846
still4given said:

Hi Mike,

I'm sorry but the pics are misleading. The things you circled are actually string. The speaker cable has a nylon string along side the wires to add strength when pulling the cable through conduit. You are seeing the tag ends of the string. I should have just pulled that piece of string out. :cannotbe:
Click to expand...

Ah, these nylons looked very metallic on the photos...
I am looking forward to your impressions with using dual supplies !

Mike
 
#1,850
There are many guys waiting for Symassym hi power, i suggest that to many friends

That asked me to suggest a good power unit.

This way, please, do not forget to produce , or at least, give us some possible dead line about that.

We know you are busy, reason why we are waiting.

I will be more happy, knowing how many days, weeks or monthes i will be waiting for you, Mr. Michael.

So, if you can make a special kindness, related to let us know what is going inside your mind, related your own dead lines, and also, if you are happy to do a bigger powered unit or not, well, those informs will be very good...as people will have the chance to decide to wait or not to wait.

Yes, i know you already published something with more power...but not the "Big Brother"

The time you was learning is finished..you are now a well known, famous and respectable designer, and your customers, not paying nothing, but attached to you, are needing things from you...sorry, but you are now some kind of public guy, that have some obligations...the fame reduces our freedom too.

As the Chinese use to say:

- You are totally responsable related the friends you made...so, after making them, you have to support them, and keep them with you....keeping in touch, and giving attention to them...

Public personalities cannot say no!...just can say..".in the correct time you will have the power unit".

Chinese Milenium knowledge.

Mr John Mateus was the one that helped you.... having the risk to be misunderstood...because he said..."oscilating"...."rasppy sound"..."harshing sound"...this one, the first that was true with you, helping you to face the reality of those early designs...this one.....your friend Mateus.....he is asking a bigger power unit.

regards,

Carlos
 
#1,851
Carlos,

I do not want to be offending or suggesting much. But there might be a great difference between the point of view of the one who is almost unemployed and the one who is under permanent pressure in his regular job and company, exhausted in the envenings, and helping the hobbyists, who are never satisfied!!

Surprisingly, they are the people under permanent pressure and lack of time who come with new ideas and help, not the unemployed people, who have time more than enough, as often seen. How is it possible??
 
#1,852
Yes, i agree with you...totally, but even this way he can tell us

What is the year period he beliefs, as beeing adequated to design that, as he has his own dead lines related his company.

Just to tell us something alike:

"It is probable that around July i will have time enougth to dedicate to this design".

This way, people interested in this design, will decide if will wait or not.

regards,

Carlos
 
#1,853
Re: Yes, i agree with you...totally, but even this way he can tell us

destroyer X said:
What is the year period he beliefs, as beeing adequated to design that, as he has his own dead lines related his company.

Just to tell us something alike:

"It is probable that around July i will have time enougth to dedicate to this design".

This way, people interested in this design, will decide if will wait or not.

regards,

Carlos
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How is there a decission? It's not like you will find the design somewhere else? I guess they could decide to build something else while they wait. 😀

Blessings, Terry
 
#1,859
Mostly stuffed, waiting for a few transistors and the transformers for two stereo amps.

Transformers are 25vAC, 500VA (one per amp), caps are 4x8mf per channel.
 

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