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Old 25th January 2003, 09:56 AM   #61
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Hi John,

Is there any minimum or ideal distance to keep between the driver and the output transformer?

I will make the box bigger than necessary just to avoid too much wires on a very little area – for safety reason.

The price 462,20 for a custom made output transformer is a reasonable “level” if I compare to Lundahl and Audio note, however I can not judge the “absolute” quality. I trust your research and the outcome in terms of noticable sound quality. The only thing I can do, to understand the quality, is to compare the sound with a commercial product like Cary or Audio Note. I know this is very difficult if you do not do a A/B comparison, but is it possible to say what the sound compares to?

The Power transformer: I’m waiting to see the specifications for this as soon as you have developed this design to your final (is that possible) preferences. I’m in no rush to finish the project, it must be done right from the beginning, and if it takes time to develop this, I respect that.

Finally I should place an order for the output transformers, the drivers and the power transformer at the same time from Wil.

“...So, you could either build in a switched source selsctor and volume control, or, build a "passive preamp"....” I think a passive preamp suits me best so I can concentrate on the schematic you have already presented – unless its not too time consuming or difficult for you to explain what kind of modificiation in your schematic that has to be done to include source selector and volume control. And I chose the non-balanced version to simplify the power supply.

Looking forward to see the pictures! And thank you for sharing your knowledge!


Per
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Old 25th January 2003, 10:15 AM   #62
dhaen is offline dhaen  Europe
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Per,

IMO there is no minimum distance between these transformers. as long as they are mounted with their laminations at 90 degrees to each other.

I cannot give you a quality comparison with other transformers. I have no "flowery words" to describe their performance, but will publish some more detailed measurements.
Nor have I experience of many commercial amps. However, I do work in the broadcast industry, and have listened to many studio amps. Of course they tend to sound different to a home installation, but I have some experience in assessment.

IMO the driver and output transformers should come from the same source, if only for cosmetics.
The power transformers and chokes can come from any reputable source, though you might find that AE prices are attractive.

I'm sure there are schematics of "passive preamps" out there. A glance at one or 2 will show you how simple they are.
Since it fits between the sources and the amp input, I'm sure you'll see it is a trivial problem.

Cheers,
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Old 25th January 2003, 10:45 AM   #63
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Quote:
Originally posted by dhaen

I'm sure there are schematics of "passive preamps" out there. A glance at one or 2 will show you how simple they are.
Since it fits between the sources and the amp input, I'm sure you'll see it is a trivial problem.

Cheers,
OK, that sounds good.

regards,
Per
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Old 25th January 2003, 10:55 AM   #64
dhaen is offline dhaen  Europe
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Default Please excuse my manners...

Per,

What I should have said about the comparison and evaluation issue, is that if you are in the UK in the near future, you should visit and listen for yourself.

Cheers,
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Old 25th January 2003, 11:04 AM   #65
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Default Re: Please excuse my manners...

Quote:
Originally posted by dhaen
Per,

What I should have said about the comparison and evaluation issue, is that if you are in the UK in the near future, you should visit and listen for yourself.

Cheers,
Thank you, listen is the only (best) way of course.
Last time I went to UK was, 1983.....
It's a petty I don't have the possiblity to go there this year, but thank you anyway.

per
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Old 25th January 2003, 11:36 AM   #66
dhaen is offline dhaen  Europe
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Default Changes..

Per,

Quote:
Last time I went to UK was, 1983.....
Mmm, a lot has changed since then. IMO mostly for the worse.

Cheers,
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