B1 Buffer Preamp

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.
 
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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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?
 
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
 
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'
 
I'm gonna make a small LM317 (or LT317) regulated powersupply myself using the Velleman K1823 kit. Batteries tend to be empty when you really need them most.

I agree, Batteries are goodm but when your in that mood to listen to some nice music, they usually are dead :(

I'll will probably try a few things.

A) SMPS from a laptop similar to a walwart.
B) walwart adapter 18V around 1A
C) Battery
D) Build my own psu, I have this REALLY nice case i will use for this :)

Jase
 
Can I use a lightspeed attenuator with the B1? I`ve seen the topic been mentioned in the thread earlier but I havent got a definitive answer to this. Are there any problems doing this? I know the lightspeed have a lower resistance than the 25k that is recommended for the B1. Will the low resistance of the lightspeed cause any problems in this combination (or any other problems)?
 
Hi everyone,
2 friends and I are building the B1, we will be using this regulator:

Variable DC Power Regulator 0-24V (up to 5A) DIY kit on eBay.ca (item 320381554298 end time 05-Dec-09 08:43:53 EST)

Also for those who may be interested we will order a toroidal transformer from a local company who manufactures them for the audio and medical industries. I will post the information before ordering and if enough interest might make a small group buy.
Regards,
Eric


Plitron ? in Ontario ?