ok, sounds good.
so on to the next question: i intend to power the B1 with batteries. I thought about 2x9V batteries. Now i read that the rechargeable 9V batteries only supply 8,4V. So two of those would add up to 16,8V instead of the recommended minimum of 18V. Is that likely to cause any problems?
so on to the next question: i intend to power the B1 with batteries. I thought about 2x9V batteries. Now i read that the rechargeable 9V batteries only supply 8,4V. So two of those would add up to 16,8V instead of the recommended minimum of 18V. Is that likely to cause any problems?
No problems. Will work beautifully.
A €10 19v laptop brick will work just as well, and not need recharging...
A €10 19v laptop brick will work just as well, and not need recharging...
thanks! i think i'll go with the batteries. i really can't stand the look of those bricks. it's all for aestethic reasons 😀
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You might want to do a quick search on batteries as a power supply for low-level audio signal circuitry. Batteries of nearly all types tend to throw off a large amount of high frequency noise. It may not matter in this application (I haven't tried)...
I use 3x 9v batteries , good for around 80 hours , with AC I go with regulator 24/30vdc max
i thought the opposite was the case and people value batteries in hifi for steady supply and low noise 😕
The advantage of batteries is the decoupling from the mains. It's free of mains hum and mains harmonic.
I wouldn't worry about HF noise from batteries, try it, if there ends up being an issue, there are other avenues to explore.
I wouldn't worry about HF noise from batteries, try it, if there ends up being an issue, there are other avenues to explore.
I find, and I think I have heard Zenmod also say?, the M2 comes alive with a little gain. Even with my higher efficiency speakers, >100 dB, this is true, and to a greater degree with lesser efficient speakers.
That said, it will sound great within its gain limitations and your listening preferences, room size, etc.
Russellc
I tried batteries, laptop power supply, and as you know, there same regulated power supply you used in this build thread.
I couldn't tell a great deal of difference between the batteries (2 x 9 volt) and the laptop supply. The simple regulated supply you outline in build thread beat them both by a noticeable amount (imho) across the board.
The commercial B1 used a wall wart if I recall without problems.
Russellc
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Hello guys!
Does anyone know which transformers to use for Xformer gain version of the B1 line stage?
Does anyone know which transformers to use for Xformer gain version of the B1 line stage?
Finally my B1 is up and sounding fantastic! A perfect match for M2 and horn speakers (102dB).
50VA transformer, Salas BiB (19V), B1 PCB from passdiy, chassi from modushop.biz
The inside image just lacking cables from the regulator. Front with a not blue led 😉 .
50VA transformer, Salas BiB (19V), B1 PCB from passdiy, chassi from modushop.biz
The inside image just lacking cables from the regulator. Front with a not blue led 😉 .
Attachments
Hi sov,
Is that a transformer from Toroidy.pl in your b1.?
Are you happy about this toroidal.
I have a 500w one for my M2 , but I have not tested it yet!
Is that a transformer from Toroidy.pl in your b1.?
Are you happy about this toroidal.
I have a 500w one for my M2 , but I have not tested it yet!
Yes it is. I had a Toroidy 300VA in my M2 but upgraded to a Toroidy 500VA. They perform well. I like the filled center and the m6 bolt holds them quietly in place.
The size surprised me as well. 🙂 They are certainly not a necessity and I can not give them all the credit for the good sound. It was fun building though.
Hi all,
I was checking some Toshiba 74bl and 170bl following this post, so using a 100r.
I noticed that the voltage reading on the DMM tend to show the value I was expecting for few seconds, then the value tend to drop a bit, So I took them off, just afraid of destroying them.
Is that safe for the fets to stay few seconds powered up in this configuration ?
How to interpret the voltage deviation?
Thank in advance!
I'd like to squeeze my B1 into a very low enclosure with only 40mm internal height. I think the only part that could be hard to fit are the power supply caps C1 and C2. The manual says to use caps rated at 25v 1000uF to 15000 uF. Will it make any difference if I use ones closer to 15000 or closer to 1000?
I'm massively overwhelmed with the variety of caps out there. Can someone point me in the right direction of which ones would be suited?
I'm massively overwhelmed with the variety of caps out there. Can someone point me in the right direction of which ones would be suited?
Hello Sov
Congratulations nice B1 build!
M2 amp first stage is a similar impedance jfet buffer but without volume knob.
Now with 102dB horns all you need is audio source with out signal = 2V,
stepped attenuator, autoformer volume control, light depended VC , or potentiometer etc.
and connect this directly to M2.
I know it's work great after my personnal successful experience with M2.
Maybe experiment a little and You decide if is useful to keep B1 in the audio chain with M2 ?
🙂
