smps power bricks have such high efficiencies, better than linears and quieter too based on my experience...
50 watts into 4 ohms and 25 watts into 8 ohms can only be possible with a very stiff psu, and smps power bricks are one such psu...
the mark levinson ML2 is 25 watts into 8 ohms....and very heavy and the standard by which i look at other class A amps with, anything less than this and i grow skeptical....can you blame me?
What are you looking for in comparison to the Mark Levinson that makes you skeptical? It has oversized passive radiators and probably runs quite cool for a 25w Class A. Most of the DIYA 25w Class A amps work fine with a 4U x 300mm x 40mm deep fin chassis. I have used 24v SMPS on a Class A too. Works quite well. Regarding “stiffness” of Class A PSU’s. They run a continuous load of the same current flow. Stiffness or as I interpret that as low impedance PSU is more important for Class AB where the current demand varies drastically with the music is more important.
oh, i have seen and heard 12 of these ML2 amps in action, very awesome....all 12 in a system comprised of 32 boxes of speakers, together with 4 crown Macrotech reference amps driving 4 subwoofer boxes....wall of sound, the owner called it...
classic class A amps are heavy and inefficient, that was then, and now with smps psu, some weight and inefficiencies can be chalked out.....
classic class A amps are heavy and inefficient, that was then, and now with smps psu, some weight and inefficiencies can be chalked out.....
Not side by side as M2X used to reside in the same chassis. I had M2X with Austin and SLB. It was a nice setup with low noise once I had mumetal on the Edcor and ran RCA ground to star hub. M2X is a bit softer in bass authority and perhaps more relaxed and richer and thicker sound. With complex stuff like heavy metal the M2X could get lost. Sounded very nice though for a lot of music. The AN’s extra power is really handy for my low sensitivity speakers. I think AN is one of the most resolving amps I have heard. The detail is superb but there is no harshness or fatigue.
Some cheap 5A 24v SMPS have fake (unconnected earth ground) even though it’s an 3 prong EIC. This means that the negative is floating and you can connect two in series for a handy +/-24v 5A Class A PSU. I did it on an M2 experiment a few years ago.
I used something like this a few years ago. These might be true grounded now as they are supposedly UL certified.
SUPERNIGHT Power Adapter, Transformers, Power Supply for LED Strip, Output 24V DC, 5A Max, 120 Watt Max, UL Listed (Output 24V DC, 5A) https://www.amazon.com/dp/B00LUIKY4S/ref=cm_sw_r_cp_api_i_pLz8DbVVZ9MN9
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getting two of them in series is the work around....
there are smps with trimpots to tweak the output voltages....
i am now inclined to use them although i wind my own traffos used in my projects, we will even use them in tube amps....
https://www.lazada.com.ph/products/...964945.html?spm=a2o4l.cart.0.0.56783e172AVfCI
https://www.lazada.com.ph/products/...315780.html?spm=a2o4l.cart.0.0.56783e172AVfCI
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for safety reasons, the primary side of any smps is isolated from its secondary that provided the dc outputs...
Would a +/-24v SMPS like this do the job?
500W Dual voltage LLC Switching power supply board for power amp PSU DIY L7-31 | eBay
500W Dual voltage LLC Switching power supply board for power amp PSU DIY L7-31 | eBay
My one experience with a compact switch mode PSU like this (actually a $150 Connexelectronic 800w unit that looks very similar) showed a lot of noise in the high frequency audio range (hiss) that could not be suppressed. When I changed to a generic stainless steel cased box with screw terminal block high power LED PSU from China, the noise was absent. In fact it was astoundingly good. The amp went from hissy to absolute silence. This was an 800w 48v (adjustable to 51v) smps that I used for a Class D amp. I would imagine two of these in series could make anfine dual rail solution. However, internally the earth protective ground is tied to the -ve (0v) output. This would have to be modified (at one’s own risk) to allow dual rail series connection.
One other mod was that I was using at 1/4th rated power similar to TonyTecson, so I disconnected the noisy internal cooling fan on the PSU. Not needed for such low powers as the chassis aluminum block was sufficient.
Look at the noise floor from this SMPS and TPA3255 amp combo (20w into 3.3ohm load):
Here is the setup, this was a $44 800w 48v SMPS from AliExpress free shipping!
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Nope. Then I considered that I wanted more power, thinking of a use with more options and not only for near field with my speakers of 85 dB and minimum 3.9 Ohms.
I have to accept that I can only enjoy my music with the second system, in near field and room much smaller than the living room.
I have a problem: in these years I have achieved an impressive improvement in this second team by spending very little. The last one was days ago with the Miflex KPCU-01 0.01uF as a bypass. Probably tomorrow I will change the resistors for some Mills 5 watts. I am talking about my modded KEF Q100 speakers.
PS: only here I am maty tinman.
Thanks for info X. I run most of my systems as biamped, using class A from 150Hz up, AB for woofers. Not much demand for Class A amp to drive, I only care about lush midrange and crystal clear heights. I settled on M2 so far.
I may built AN eventually. I like that it uses all available parts, no unobtainium jfet or SITs. Great work!
I just got a new desktop DAC hat uses the AK4490. It is the SMSL Sanskrit 10 - under $100 and has DSD capability and 2Vrms output drive. It needs an external USB power supply to work at its best (just the PC USB cable is sub-optimal). It claims 0.0005%THD which has been independently verified elsewhere.
Here is 11.01Vrms (12.1W) into 10ohms. It seems that the noise floor is a bit lower than with the Cayin N3.
Here is 11.01Vrms (12.1W) into 10ohms. It seems that the noise floor is a bit lower than with the Cayin N3.
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I don't think you can run this from a phone. It is for PC/Mac only. There are detailed measurements here showing 6Vpp (2.12vrms) output and distortion:
Review and Measurements of SMSL Sanskrit 10th DAC | Page 2 | Audio Science Review (ASR) Forum
I did not measure output on and O-scope myself but did measure the output of my amp, and this DAC can definitely drive it to clipping levels - more powerful than my Focusrite DAC.
Review and Measurements of SMSL Sanskrit 10th DAC | Page 2 | Audio Science Review (ASR) Forum
I did not measure output on and O-scope myself but did measure the output of my amp, and this DAC can definitely drive it to clipping levels - more powerful than my Focusrite DAC.
