Hi guys, sorry for the silly question :
Is b1 everytime suitable for double outputs?
Can I simply split the signal out or do I need something more to drive two stereo amps from it?
Thank you very much!
Regards!
Is b1 everytime suitable for double outputs?
Can I simply split the signal out or do I need something more to drive two stereo amps from it?
Thank you very much!
Regards!
What I mean is: better thinking about using something like this (only left channel shown) :
to avoid any impendance problem with two amps connected to the buffer?
Thank you, guys!
to avoid any impendance problem with two amps connected to the buffer?
Thank you, guys!
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simply add a R104 for an extra output. Similarly add an extra r204 for the other channel.
You now have two outputs each with an output impedance of ~1k0
You now have two outputs each with an output impedance of ~1k0
Fancy caps, worth the spend?
There are few capacitors in the B-1, so the temptation is to splurge on really good ones, at least in the signal path. But will I hear the difference between Axons, ($1.25 for 1.5uF at Parts Connection) and Auricaps ($15.58 for 1uF at same) and does the .5uF difference matter? Pardon my nube question. This is my second diy and the first one had a pretty explicitly bom.
Cheers,
Larry
There are few capacitors in the B-1, so the temptation is to splurge on really good ones, at least in the signal path. But will I hear the difference between Axons, ($1.25 for 1.5uF at Parts Connection) and Auricaps ($15.58 for 1uF at same) and does the .5uF difference matter? Pardon my nube question. This is my second diy and the first one had a pretty explicitly bom.
Cheers,
Larry
Thank you very much, Andrew!
Simple and effective!🙂
You can also find very cheap and good (IMHO) NOS russian caps on ebay...
The teflon K40, for example...
Or the 10uf PETP's....
You can use NOS Russian PIO caps, they are better then most cheap to mid price audiophile caps (for example better than BG N used as signal caps), but try to source Siemens MKV caps, they are available on eBay, unfortunately no longer for very little but they are still cheap considering they are one of the very few best caps you can get. There are probably few slightly better signal caps in the world but cost a small fortune like few hundreds $ for a cap.
I just built B1 with Siemens MKV and Caddorck resistors, Aerovox PS caps and battery powered, but I'm not quite sure I like it with my Aleph 3. It sure sounds fine and high quality but somehow little flat and (not considering dimensions of soundstage but rather air around voices and instruments) not involving.
I just built B1 with Siemens MKV and Caddorck resistors, Aerovox PS caps and battery powered, but I'm not quite sure I like it with my Aleph 3. It sure sounds fine and high quality but somehow little flat and (not considering dimensions of soundstage but rather air around voices and instruments) not involving.
6-channel B1 buffer preamp
Just finished my 6-channel B1. All running from one PSU. Input caps 0.1uF teflon and no output caps (I have settled on fitting input caps only to amps and preamps, as you know exactly what value of cap is required for the input impedance and avoid doubling up on coupling caps). Thanks Nelson 🙂
Just finished my 6-channel B1. All running from one PSU. Input caps 0.1uF teflon and no output caps (I have settled on fitting input caps only to amps and preamps, as you know exactly what value of cap is required for the input impedance and avoid doubling up on coupling caps). Thanks Nelson 🙂
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Congratulation,
Pretty big input cap's😱 = - - - - noise!
I like your minimalistic point to point. How do you find the sound? Did you use the SK-170?
Cheers,
Eric
Pretty big input cap's😱 = - - - - noise!
I like your minimalistic point to point. How do you find the sound? Did you use the SK-170?
Cheers,
Eric
Thanks Eric. C1 is now 1ohm>150000uf>0.22ohm>15000uF>0.22ohm>15000uF and C2 is 68000uF. Takes about half an hour to get going though 🙂
Yes, Yes. Design the DC blocking where it is needed and can be designed for. All else does not need extra DC blocking.
I love the P2P mounted directly to the RCA/Phonos.
I even like the idea of plugging in half an hour before intended serious listening and then unplugging for the serious relaxation time.
Verry interesting, and nice job.....how do you intend to use it? In a multi-room setup, or maybe for surround?
Thanks guys. Not the neatest build but does the job. It's been powered on continuously since I first posted (still not installed bypass caps across each pair of fets, but will do this at some point). I disconnected the cheap 18V switch mode power supply I used initially and connected up a regulated linear supply of 24V 500mA - the swap took a minute or two but the preamp kept playing throughout 🙂
I forgot to say that I used matched (within 2%) pairs of 2SK170 fets - actually three sets of matched quads (to give me three pairs of matched channels).
A while ago I modified a DCX2496 with Jensen output transformers (standard active output stage completely bypassed). I plan on using this with a DEQ2496 (due any day) and SRC2496 (as digital source selector and upsampler) to give me a 2x3 way digital crossover solution. I've also built 6 channels of TK2050 power amplification (one stereo amp using Arjen Helder TK2050 mono boards & one quad amp using Sure TK2050 stereo boards - both amps use higher grade Meanwell 24Vdc SMPS). The 6 channel B1 completes the system and will allow me to play with 3-way speakers in the future (I use 2-way Martin King open baffles right now with mono sub - the system will cope with these too).
I forgot to say that I used matched (within 2%) pairs of 2SK170 fets - actually three sets of matched quads (to give me three pairs of matched channels).
A while ago I modified a DCX2496 with Jensen output transformers (standard active output stage completely bypassed). I plan on using this with a DEQ2496 (due any day) and SRC2496 (as digital source selector and upsampler) to give me a 2x3 way digital crossover solution. I've also built 6 channels of TK2050 power amplification (one stereo amp using Arjen Helder TK2050 mono boards & one quad amp using Sure TK2050 stereo boards - both amps use higher grade Meanwell 24Vdc SMPS). The 6 channel B1 completes the system and will allow me to play with 3-way speakers in the future (I use 2-way Martin King open baffles right now with mono sub - the system will cope with these too).
Just added 6x 0.1uF Russian polystyrene caps across the voltage and ground rails (one beside each transistor pair). Don't hear any immediate difference but I'm still listening with a pair of old speakers in my kitchen (and it will probably take 15mins for voltages to settle after power was switched back on).
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Hi,
I bought one of these DC Panel mount jacks off ebay.
When measuring at the pins on this DC jack, the neg or gnd return
is shorted to the chassis. It looks like it is by design.
Is it safe to use this DC jack since it ground return would be through out
the chassis?
I could not locate one that has all pins isolated. Do you know of one
from mouser? PN# would be great.
Thanks
I bought one of these DC Panel mount jacks off ebay.
When measuring at the pins on this DC jack, the neg or gnd return
is shorted to the chassis. It looks like it is by design.
Is it safe to use this DC jack since it ground return would be through out
the chassis?
I could not locate one that has all pins isolated. Do you know of one
from mouser? PN# would be great.
Thanks
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Whether it is safe or not is relative to the way you setup everything. If you want to isolate both conductors here is one possibility as there are a lot of jacks that are similar to the one you showed us.
KPJX-PM-4S-S Kycon DC Power Connectors
Cheers,
Eric