Anybody experiment what is SMPS difference between power on-off at DC side
and probably much less thumb noise into speakers if the switch power on-off position is at the 110/ 230V AC side ?
Cheers
No noise on mine with switch on AC side but I added a CL-140 thermistor in series. There is also a 33k uf cap in parallel with the DC output. I removed the resistor/diode combo because it still produced the turn on “fart”.
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I think I’m going to build a B1 for my ACA’s as I finally have time to build the amps. Is there any reason I couldn’t have the power for the B1 supply power to the monoblocks through umbilicals? Reason I ask is I really don’t need three more units to try and find outlets for in an already cramped space. Also, would it be worth it to go ahead and run off 24v?
Yes, you could daisy-chain the power through the B1.
24v for the amp is worth it.
Here's a possible solution for your outlet issue -
Yeah, have one or two of those. Turntable, three headphone amps, CDP, music streamer, two tube amps, and receiver so far in a 11x11 foot room that shares an office desk and guitar gear. Looks like I’m starting a cable supply company behind the rack
Limited mainly by j-fet dissipation I would say. Voltage limited as well to more or less 32V for the 2sk170 (lsk170 I am not sure...) as well as per NP advice (see F5 turbo article).
After that comes heatsinking the output transistors.... and in the end comes the bigger hammer approach of ZM...
EDIT: Stay with 24v (or so) or build something else - unless someone here want's to chime in to complicate a simple project
After that comes heatsinking the output transistors.... and in the end comes the bigger hammer approach of ZM...
EDIT: Stay with 24v (or so) or build something else - unless someone here want's to chime in to complicate a simple project
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Frankenbox ACA amp
Finished last night, biased first try each half, 10.1vdc as per original design specs at 19vdc. Presently using wall warts supplies, but have built a linear supply for future fun. The enclosure is made of salvaged heat sinks from the dumpsters, built as two separate half of the whole. Removing 4 screws give access for mods and maintenance. Two posts are mounted next to the output cap to allow future bypass experiments without violating the circuit boards. I did use better quality parts near the input and feedback, hoping for a nice return in sound. Yes, this little guy sounds very nice. I am surprised it handles the 91db speaker as well, with enough power for most listening sessions.
The result of this project motivates me to build either an M2 or F4, it's that kind of experience listening to this type of amp.
Thanks Papa, and to others here on DIYaudio!
Finished last night, biased first try each half, 10.1vdc as per original design specs at 19vdc. Presently using wall warts supplies, but have built a linear supply for future fun. The enclosure is made of salvaged heat sinks from the dumpsters, built as two separate half of the whole. Removing 4 screws give access for mods and maintenance. Two posts are mounted next to the output cap to allow future bypass experiments without violating the circuit boards. I did use better quality parts near the input and feedback, hoping for a nice return in sound. Yes, this little guy sounds very nice. I am surprised it handles the 91db speaker as well, with enough power for most listening sessions.
The result of this project motivates me to build either an M2 or F4, it's that kind of experience listening to this type of amp.
Thanks Papa, and to others here on DIYaudio!
Attachments
So I am going to throw my 2 cents in here. Sorry. I already voiced my desire for this in the survey for black Friday sale losers.
I would like to see a nutube buffer built into the ACA, or nutube buffer expansion board... even a stand alone nutube buffer component. That would be nice.
I think a lot of the people who are interested in the ACA are folks who can't afford the high end stuff and are willing to put in elbow grease to make up the difference, assuming it is not too complex. Those people with budgetary limitations are also not likely to have high end sources either. This is where mellowing the harshes can result in significant improvement, unlike higher end gear.
Korg is selling the nutubes to diyers. Considering Nelson already designed a nutube buffer in the same voltage range, might this be attainable? Or easily performed doing it on your own?
I would like to see a nutube buffer built into the ACA, or nutube buffer expansion board... even a stand alone nutube buffer component. That would be nice.
I think a lot of the people who are interested in the ACA are folks who can't afford the high end stuff and are willing to put in elbow grease to make up the difference, assuming it is not too complex. Those people with budgetary limitations are also not likely to have high end sources either. This is where mellowing the harshes can result in significant improvement, unlike higher end gear.
Korg is selling the nutubes to diyers. Considering Nelson already designed a nutube buffer in the same voltage range, might this be attainable? Or easily performed doing it on your own?
Well....
We studied the surveys, and we have your message here. And one way or another we'll make your wish come true! BUT is it a new amp or a separate buffer or preamp? We don't know..so the only solution is to wait wait wait..
We're slow but we try very hard not to break promises..
Mark
We studied the surveys, and we have your message here. And one way or another we'll make your wish come true! BUT is it a new amp or a separate buffer or preamp? We don't know..so the only solution is to wait wait wait..
We're slow but we try very hard not to break promises..
Mark
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