Help needed,
When using only the powerstage Like is suggested in the ba1 article. which parts can be removed and which other ajustments have to be made.
Thanks in advance for any help.
When using only the powerstage Like is suggested in the ba1 article. which parts can be removed and which other ajustments have to be made.
Thanks in advance for any help.
Thank you so much,
I'm just in te process of designing the layout for two hard wired monoblocks.
Each monoblock will consist of two aluminium profiles mounted to the left and richt side heathsink of a mono chassis. One side will carry the upper halve of the gain stage and the other side will cary the down halve of the gain stage.
This construction will provide me an easy way of trying different desings. or circuit boards.
power supply 1000 va and 300.000 mf per channel.
Hope there will be enough voltage delivered by my Wadia 830..
Thanks you so much again.
René
I'm just in te process of designing the layout for two hard wired monoblocks.
Each monoblock will consist of two aluminium profiles mounted to the left and richt side heathsink of a mono chassis. One side will carry the upper halve of the gain stage and the other side will cary the down halve of the gain stage.
This construction will provide me an easy way of trying different desings. or circuit boards.
power supply 1000 va and 300.000 mf per channel.
Hope there will be enough voltage delivered by my Wadia 830..
Thanks you so much again.
René
With that power, just be sure you put inrush current limiting in front to avoid poping fuses 😉
But I guess you know that already 😉
Hannes
You are probably not to good at guessing. 🙂
To be honest I did not think about this yet.
Never worked with amps consuming these high currents.
But since you mention I do remember this might become an issue.
Do you know of any simple solution for this?
To be honest I did not think about this yet.
Never worked with amps consuming these high currents.
But since you mention I do remember this might become an issue.
Do you know of any simple solution for this?
Simplest way is to try the big CL-60 thermistors in series with the primaries.
There are also more complicated ways with soft-start circuits that e.g. bypass a series resistor after a certain time. I like the simple solutions, usually very effective!
Hannes
There are also more complicated ways with soft-start circuits that e.g. bypass a series resistor after a certain time. I like the simple solutions, usually very effective!
Hannes
I am glad I SPENT THe few extra bucks to get the transformer with dual 115V primaries now. Do I use the same CL60 thermistor for that? it is a 225VA 12V jobbie for the mini A???
What is not very cheap. In case you can only get 5 May be we could arange you sent two of them over to me....depending on where you are and how much additional costs that will bring
Current
Hi, someone could measure the total current per channel?
I have two PT 25-0-25V 250VA can serve for this amp??
Thanks
Hi, someone could measure the total current per channel?
I have two PT 25-0-25V 250VA can serve for this amp??
Thanks
Hi,
the 250VA 25+25Vac transformer has a maximum continuous current rating of 5Aac.
When using a capacitor input filter after the rectifier. the maximum continuous DC current rating is ~2.5Adc.
The amplifier continuous DC current draw must not exceed 2.5Adc and for cool running I recommend that the continuous operational current be limited to ~50% of maximum rating, i.e. <=~1.3Adc continuous.
What is the current draw of your amplifier?
How many channels do you want/need to supply from this transformer?
the 250VA 25+25Vac transformer has a maximum continuous current rating of 5Aac.
When using a capacitor input filter after the rectifier. the maximum continuous DC current rating is ~2.5Adc.
The amplifier continuous DC current draw must not exceed 2.5Adc and for cool running I recommend that the continuous operational current be limited to ~50% of maximum rating, i.e. <=~1.3Adc continuous.
What is the current draw of your amplifier?
How many channels do you want/need to supply from this transformer?
Last edited by a moderator:
PT
Hi Andrew, thank you for reply.
Still is a project, I am collect the parts and wish know if the transformer that already have could work.
I have two of these 25-0-25V 250VA PT and maybe could use one per channel?
On the other hand though I have seen that the circuit operates at 25VDC, NP has published distortion curves at 32V too, the same circuit might work with 32Vdc?
Hi Andrew, thank you for reply.
Still is a project, I am collect the parts and wish know if the transformer that already have could work.
I have two of these 25-0-25V 250VA PT and maybe could use one per channel?
On the other hand though I have seen that the circuit operates at 25VDC, NP has published distortion curves at 32V too, the same circuit might work with 32Vdc?
If Pass says use 25Vdc then you need a very good technical reason for adopting any different voltage. Your 25+25Vac transformer will not give +-25Vdc.
Oh Lord, won't you buy me a Mercedes-Benz?
I need pcb´s to build a "full stereo version" i.e. stereo gain stage + bias board + output set (ALEPH 3 or a BA 1.
How or from whon could I buy these pcb´s and matched transistors.
It could be a preamp n .
I need pcb´s to build a "full stereo version" i.e. stereo gain stage + bias board + output set (ALEPH 3 or a BA 1.
How or from whon could I buy these pcb´s and matched transistors.
It could be a preamp n .
My next project...
I'm really enjoying my BA-3 front end and F4 power stage.
I can't help wondering if bi-amping my speakers wouldn't be a good idea.
Looking in my garage I found these...
And I have a couple of big black heatsinks weighing me down.
So I'm thinking maybe a BA-1 would be the thing to do.
My plan would be to feed both the F4 and BA-1 from the BA-3.
I guess I'd need to run the transformer with primaries in series on the 100V taps: this should give me almost 22V peak to peak.
I haven't compared the IRF244 with the IRF240 yet - hopefully they will substitute OK. I think these parts were mostly gifts from Nelson at the very first Burning Amp: it's been a while getting a plan for them.
Is this madness? Any thoughts?
tim
I'm really enjoying my BA-3 front end and F4 power stage.
I can't help wondering if bi-amping my speakers wouldn't be a good idea.
Looking in my garage I found these...
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An externally hosted image should be here but it was not working when we last tested it.
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An externally hosted image should be here but it was not working when we last tested it.
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And I have a couple of big black heatsinks weighing me down.
So I'm thinking maybe a BA-1 would be the thing to do.
My plan would be to feed both the F4 and BA-1 from the BA-3.
I guess I'd need to run the transformer with primaries in series on the 100V taps: this should give me almost 22V peak to peak.
I haven't compared the IRF244 with the IRF240 yet - hopefully they will substitute OK. I think these parts were mostly gifts from Nelson at the very first Burning Amp: it's been a while getting a plan for them.
Is this madness? Any thoughts?
tim