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Old 28th November 2009, 02:55 AM   #2001
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Quote:
Originally Posted by Beftus View Post
a budget restraints question... where do spend the largest part of my limited capacitor budget on: the 1uF caps (C100 & C200) or on the 10uF caps (C101 and C201).

I'm thinking of using Clarity Cap SA series for the 1uF and Clarity Cap PX series for the 10uF.
Vitamin Q's for the 1uF work well and are affordable
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Old 28th November 2009, 03:07 AM   #2002
labjr is offline labjr  United States
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Quote:
Originally Posted by Beftus View Post
a budget restraints question... where do spend the largest part of my limited capacitor budget on: the 1uF caps (C100 & C200) or on the 10uF caps (C101 and C201).

I'm thinking of using Clarity Cap SA series for the 1uF and Clarity Cap PX series for the 10uF.
Depends how grain-free you want to get. The Axon caps Nelson used aren't real expensive. I think they are the same as Solen caps. I'd be curious to know what Mundorf silver oil caps sound like in the circuit.
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Old 28th November 2009, 03:18 AM   #2003
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I used Nichicon kg gold for the ps caps for an audible upgrade over the Panasonics.
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Old 29th November 2009, 06:26 AM   #2004
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Quote:
Originally Posted by supernet View Post
I was looking around for quite some time trying to find a simple buffer to drive my high gain power amplifier and now I am really interested about this B1 project, so Mr. Pass are there any news about it?


Will it contain also volume control and selector as complete preamp unit?
If you want to build your own, this can be done with a single 12ax7 for both channels. The only problem is with this schematic, the output impedance will be very high... i recommend building a SRPP using 1 12ax7 per channel to be able to drive any solid state power amplifier. But here is the schematic that I came up with back in the day.. its very simplistic and will yield very good results considering the low cost of the parts and for it being so simple
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Old 29th November 2009, 08:46 AM   #2005
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Quote:
i recommend building a SRPP using 1 12ax7 per channel to be able to drive any solid state power amplifier
It is an error using the same tube for SRPP-better using one half for the low side and one half of other tube for the upper,and also having two secondary windings of the transformer for the two heaters is quite mandatory!
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Old 29th November 2009, 04:51 PM   #2006
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Originally Posted by dopkomachine View Post
If you want to build your own, this can be done with a single 12ax7 for both channels. The only problem is with this schematic, the output impedance will be very high... i recommend building a SRPP using 1 12ax7 per channel to be able to drive any solid state power amplifier. But here is the schematic that I came up with back in the day.. its very simplistic and will yield very good results considering the low cost of the parts and for it being so simple
what is the output impedance using that tube with that output filter?

and I'm not a moderator here, but is this really the best place to post about a tube circuit?
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Old 30th November 2009, 11:43 PM   #2007
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I have the B1 board all populated and soldered. Now I need a power supply. The review on the Pass labs site was made listening with a SMPS, I notice.

What might I experience if I buy an 18v SMPS? Will I introduce any horrors that will make me question the long term use of SMPS? What is a good alternative?

Many thanks
Lucas
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Old 1st December 2009, 04:27 AM   #2008
jleaman is offline jleaman  Belgium
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I'm about to order the B1 board and the matched transistors in a few days, I have some questions tho,

Will i have any problems running 2 amplifiers on each channel, I run 4 amplifiers on my setup and need to know if i will have problems running 2 per channel, will it change any sound effect or impedance ?

If so, how would i correct it, as it stands the Mini aleph's have a 1k input, will i need to change this at all ?


J'
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Old 1st December 2009, 10:36 AM   #2009
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How would this be for the B1 please:

18V 2A DC Universal Regulated Switching Power Supply on eBay (end time 23-Dec-09 14:34:58 GMT)

Many thanks
Lucas
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Old 1st December 2009, 02:36 PM   #2010
jleaman is offline jleaman  Belgium
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Quote:
Originally Posted by LucasAdamson View Post
If you really want to use a swmps why not use a laptop one ? they are cheap and probably a little bit better with there clean dc output.

I personally going to just use a walwart for now, or what i suggested.

J
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