I have found that a $150 computer workstation UPS provides excellent 120v voltage regulated and clean AC mains vs a straight from wall plug. As a bonus, you get music to play through a short blackout.
Here is what I use:
https://www.amazon.com/dp/B000FBK3QK/ref=cm_sw_r_cp_api_i_zFUvDb2VZENZY
Here is what I use:
https://www.amazon.com/dp/B000FBK3QK/ref=cm_sw_r_cp_api_i_zFUvDb2VZENZY
I wouldn't put one of those "simulated sine wave" backup supplies in the same room as my main audio system. This is the opposite of clean power, and is effectively a permanently installed Quasimodo noise generator plugged into your system. About the worst recommendation I can think of for a high resolution audio system.
I guess it all depends on particular model. When not running on batteries, it’s regulator puts out quite a bit cleaner power than my dirty mains - measured with an (checked with o-scope) and you can see the vast improvement with the FFTs from the amp. It really depends on the particular unit. I have no extra-added noise issues with this one, and it actually cleans up the dirty mains.
We had a few more successful Alpha 20 builds with the SLB posted earlier today (yesterday) by Bigaudioscotto and Raptorlightning.
Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
Very nice work, gentlemen!
Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
Very nice work, gentlemen!
Hello fellow diya. Since I am among friends, allow to me say a big thank you to Jhofland, AKSA and xkr971 for their work and time spent on developing this regulator. I stumbled upon it while doing research for my upcoming preamplifier project UGS MUSES Scion. My ambition is to give it the best "fighting" option I can so that as much as possible of the noise is pushed down to a minimum, and it has to start with the power supply. I had settled for the Salas Shunt regulator and "only" had the diya universal power supply as an option. Reading that the SLB was using active rectification and capacitance multiplier, I knew I had stumbled upon something fantastic.
Reading that at high loads, the SLB showed 1mV ripple, made me even more ecstatic. This was it. Since its a preamp, the SLB will not even break a sweat and the over sized transformers will barely be on. 48VA on an architecture that consume roughly 0.6VA... I've been in the planing stage for a while, selecting components etc. and now I finally have the PSU selected.
I am not an engineer, at best, I can call myself a designer and optimizer, so I am in need of engineers that just get it and know how to do things. This is a legendary rectifier and performance. You can all be very proud of yourself. Well done
Oneminde
Reading that at high loads, the SLB showed 1mV ripple, made me even more ecstatic. This was it. Since its a preamp, the SLB will not even break a sweat and the over sized transformers will barely be on. 48VA on an architecture that consume roughly 0.6VA... I've been in the planing stage for a while, selecting components etc. and now I finally have the PSU selected.
I am not an engineer, at best, I can call myself a designer and optimizer, so I am in need of engineers that just get it and know how to do things. This is a legendary rectifier and performance. You can all be very proud of yourself. Well done
Oneminde
Hello fellow diya. Since I am among friends, allow to me say a big thank you to Jhofland, AKSA and xkr971 for their work and time spent on developing this regulator. I stumbled upon it while doing research for my upcoming preamplifier project UGS MUSES Scion. My ambition is to give it the best "fighting" option I can so that as much as possible of the noise is pushed down to a minimum, and it has to start with the power supply. I had settled for the Salas Shunt regulator and "only" had the diya universal power supply as an option. Reading that the SLB was using active rectification and capacitance multiplier, I knew I had stumbled upon something fantastic.
Reading that at high loads, the SLB showed 1mV ripple, made me even more ecstatic. This was it. Since its a preamp, the SLB will not even break a sweat and the over sized transformers will barely be on. 48VA on an architecture that consume roughly 0.6VA... I've been in the planing stage for a while, selecting components etc. and now I finally have the PSU selected.
I am not an engineer, at best, I can call myself a designer and optimizer, so I am in need of engineers that just get it and know how to do things. This is a legendary rectifier and performance. You can all be very proud of yourself. Well done
Oneminde
Hi Oneminde,
Thank you for the kind words. The credit goes to Aksa and Jhofland for their design and layout of this superlative power supply. I finally had time to briefly read post 1 of your UGS Muses preamp project thread. That’s a fine looking preamp and I really like the old school LED matrix display. It looks like a 2SK170BL based input stage preamp. I could not find a schematic in your thread so don’t know the particulars. I wasn’t clear of the circuit requires single or dual rail voltages and what those voltages were.
The SLB could indeed work - but it would be overkill as all you need is 50VA (probably <100mA?).
I am not sure an active rectifier would do much for you - but they are inherently quieter than diodes. You would need to resize the CRC for your particular load and voltage. I bet you could aim for 20uV ripple if the current is low and the caps and resistor in CRC are properly sized.
One more thing, the PSU stage of the Yarra amplifier is a dual monoblock CRC/cap multiplier power supply expressly designed for preamps. You might consider just using the PSU from that project. While you are at it, you might consider the Melbourne preamp input stage in the Yarra. It’s interchangeable. You can go for JFET MOSFET source follower SE Class A, Wayne’s BA 2018, or any of the M2X input stages of you only need unity gain.
The Melbourne is special in that it can drive up to 52Vpp cleanly in order to power zero dB gain amps like an F4 or MOFO.
Question:
I want to use the dual rail SLB to power this amplifier: [2 pc] PCB for 56W Audio Amplifier LM3875 HiFi Amp, Gold F5
it requites between 36v to 42v for the rated power output.
I have an Antek 500VA and 50v transformer and according to XRK971:
I want to know if I can use this transformer and SLB to power the above amplifier and similar ones (I also want to build a 3886 with the same SLB and transformer but haven't ordered the PCB yet.)
I am also considering the ABBB amplifier. so I would be using the SLB with various amps rated 60watts to 100 watts and I want ot know if I can use the 500VA 50v transformer.
I want to use the dual rail SLB to power this amplifier: [2 pc] PCB for 56W Audio Amplifier LM3875 HiFi Amp, Gold F5
it requites between 36v to 42v for the rated power output.
I have an Antek 500VA and 50v transformer and according to XRK971:
I want to know if I can use this transformer and SLB to power the above amplifier and similar ones (I also want to build a 3886 with the same SLB and transformer but haven't ordered the PCB yet.)
I am also considering the ABBB amplifier. so I would be using the SLB with various amps rated 60watts to 100 watts and I want ot know if I can use the 500VA 50v transformer.
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Hi Dadbeh,
You’re transformer is way overkill for a “gainclone” type of amplifier.
For 2 channels a 300va, 2 x 26v secondaries will be sufficient.
The SLB is mainly optimized for Class A amplifiers with a steady current draw.
The ABBB has essentially the SLB integrated on the the pcb, you do not need an external psu board. Just connect the proper sized transformer secondaries to the ABBB and your good to go.
thanks for helping me out. I was hoping to be ableto use the tranny that I already have with minimal modifications but it looks like I need a new one. does this work? 45V 6.6A / 90V CT at 300VA Low Noise Audio Toroidal PowerTransformers - AS-3445 | eBay
Something like this would be fine for a stereo LM3875 build:
AS-3225 - 300VA 25V Transformer - AnTek Products Corp
AS-3225 - 300VA 25V Transformer - AnTek Products Corp
Hi Dadbeh,
I did not realize you only need to power a Class AB chipamp. The SLB will give you very low ripple, but that’s not really needed for a chipamp as they have ver good power supply ripple rejection ratio (PSRR). You probably would be fine with just a properly spec’d CRC. Even a CRCRC would be great. Maybe 9600uF 35v caps and 0.15R (3w) and you are set. That’s 6 caps and 4 resistors per channel (for a monoblock) and you are done. It will be very clean sounding.
I would love to sell you an SLB but you don’t need it in this situation.
Vunce’s recommendation of Antek As-3225 is perfect for this if you want to use one trafo for both channels. For monoblock, a smaller 200VA is probably more than enough for each channel.
I did not realize you only need to power a Class AB chipamp. The SLB will give you very low ripple, but that’s not really needed for a chipamp as they have ver good power supply ripple rejection ratio (PSRR). You probably would be fine with just a properly spec’d CRC. Even a CRCRC would be great. Maybe 9600uF 35v caps and 0.15R (3w) and you are set. That’s 6 caps and 4 resistors per channel (for a monoblock) and you are done. It will be very clean sounding.
I would love to sell you an SLB but you don’t need it in this situation.
Vunce’s recommendation of Antek As-3225 is perfect for this if you want to use one trafo for both channels. For monoblock, a smaller 200VA is probably more than enough for each channel.
oh as I said in PM I intend to use this power supply with a variety of different projects that is why I want to have the possibility to have the extra headroom (up to 42v as I originally asked you) for future projectd and more demanding applications. for this chip amp the ad says that max power rating is at +-32v so I will have a lot of headroom.
it is just that the immediate use will be for this chip amp but I don't want to build a different power supply for each project. I want to be able to drop in various amplifier modules to compare.
this is why I prefer to have the 45v secondary, as you told me. of course I don't want to just waste money so if the 45v secondary will do more evil than good then, I will gladly move to lower voltage secondary.
it is just that the immediate use will be for this chip amp but I don't want to build a different power supply for each project. I want to be able to drop in various amplifier modules to compare.
this is why I prefer to have the 45v secondary, as you told me. of course I don't want to just waste money so if the 45v secondary will do more evil than good then, I will gladly move to lower voltage secondary.
Unless you plan on using a Variac between the wall plug and your trafo primaries, a 45v trafo will always make sqrt(2)x42v or 60vdc under no load. That will blow up your chipamp which has a maximum rating of 32v. I think you might be confusing max damage ratings with headroom. Also, amps will need to have electrolytic caps rated and able to handle the higher voltage. Put 60v on a 35v cap and you will have a very dangerous explosion from the cap not unlike a large M80 firecracker.
The only way to have one power supply for various amps with various voltages is to either use a Variac (but that’s risky as an inadvertent change in voltage will expose lower voltage rated parts to high voltage that can kill it or cause explosions). A safer thing to do is to have several trafos on hand. I have quite a donut collection from Antek.
9v, 12v, 15v, 18v, 20v, 22v, 25v, 28v, 32v, 35v, 42v etc.
You might want to spend some time reading this excellent summary of linear PSU design by Elliot Sound Products.
Linear Power Supply Design
Note that working with mains voltages is potentially lethal so please educate yourself or work with someone who has experience with this and can help you. Start small for practice. A 10VA 12v trafo for a circa +/-15v and diode bridge and CRC for a preamp is a good project to learn the basics without causing a huge explosion. Even then, the mains is still 120VAc and if you power a 6.3v electrolytic cap with 15v, there will be fireworks!
The only way to have one power supply for various amps with various voltages is to either use a Variac (but that’s risky as an inadvertent change in voltage will expose lower voltage rated parts to high voltage that can kill it or cause explosions). A safer thing to do is to have several trafos on hand. I have quite a donut collection from Antek.
9v, 12v, 15v, 18v, 20v, 22v, 25v, 28v, 32v, 35v, 42v etc.
You might want to spend some time reading this excellent summary of linear PSU design by Elliot Sound Products.
Linear Power Supply Design
Note that working with mains voltages is potentially lethal so please educate yourself or work with someone who has experience with this and can help you. Start small for practice. A 10VA 12v trafo for a circa +/-15v and diode bridge and CRC for a preamp is a good project to learn the basics without causing a huge explosion. Even then, the mains is still 120VAc and if you power a 6.3v electrolytic cap with 15v, there will be fireworks!
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