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Old 15th October 2010, 04:18 PM   #2671
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The build was pretty easy. The good thing about it being not too difficult is the ease at which parts can be substituted for others. Cap & resistor swaps are common with B1 builds.

In my build, not put in an enclosure as yet, I use a mix of Obbligato Premium 1uf & Russian 10uf K73-16 Caps (Output) & Naked Vishay 330r resistors where they will have the most effect on the sound quality.

The B1 is great to work with & even better to listen to.
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Old 15th October 2010, 10:57 PM   #2672
Atilla is offline Atilla  Norway
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Simle designs, that have amazing properties are lovely, aren't they? B1 is pretty much the perfect example.
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Old 16th October 2010, 12:54 AM   #2673
Atilla is offline Atilla  Norway
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BTW, kudos for the Obbligatos - I use the film-in-oil ones and they're so good I probably wouldn't use another brand unless size restricts me. I can imagine the premium foil ones aren't any worse either

Also - not "smile" designs, but "simple" designs (re: last post). Although the B1 makes me smile
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Old 16th October 2010, 08:09 AM   #2674
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Now the cct. brd. is finished I had a quick listen. Seem to have good low-end weight. More to come.
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Old 18th October 2010, 11:52 AM   #2675
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I have had a brief listen on my main system with my 6AS7 SET power amp. Bass is light with mids/treble absolutely fab. Sound stage and imaging stunning. I will trial the B1 on a high-end DIY discrete 200W transistors amp soon. Gain is a bit low for my SET.

Playing a gold pressing, re-mastered Frank Sinatra CD which is the best I have heard this CD. More to come.

Case is Hammond. Gold RCAs with selectable inputs. 4oz solid brass black chrome knob on Alps blue velvet. Inside all the hook-up wire is cotton coated, tinned solid copper wire. Hard to work with.

PS in a Toshiba 19V 3.5A SMPS.
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Old 18th October 2010, 11:22 PM   #2676
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Cotton coated wire for an SMPS supplied board
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Old 18th October 2010, 11:57 PM   #2677
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Quote:
Originally Posted by mhouston View Post
I have had a brief listen on my main system with my 6AS7 SET power amp. Bass is light with mids/treble absolutely fab. Sound stage and imaging stunning.
There are some resistors to swap from original schematic to improve bass. I don't have time to look right now but I think there are 4x 1k resistors that I swapped for 100R. The difference in the low end is huge. It will be fairly early in the thread...

Best,

Chris
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Old 19th October 2010, 03:07 AM   #2678
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Quote:
Originally Posted by chrismercurio View Post
There are some resistors to swap from original schematic to improve bass. I don't have time to look right now but I think there are 4x 1k resistors that I swapped for 100R. The difference in the low end is huge. It will be fairly early in the thread...

Best,

Chris
I left the preamp on over night and bass has lifted. More to come.

Done some tests; -3db points 5hz -> 780Khz. Peak voltage (p2p) into 10K = 13V, into 1K = 8V p2p.

"Cotton coated wire for an SMPS supplied board "
I'll assume you like both??
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Old 19th October 2010, 04:41 AM   #2679
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Quote:
Originally Posted by chrismercurio View Post
There are some resistors to swap from original schematic to improve bass. I don't have time to look right now but I think there are 4x 1k resistors that I swapped for 100R. The difference in the low end is huge. It will be fairly early in the thread...

Best,

Chris
There has been much talk about changing the 4x1k resistors you are talking about with Naked Vishay 330r's. Improvements have been noted.
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Old 19th October 2010, 04:42 AM   #2680
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I have 100r kiwame's.
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