Dreaming of a DIY 8W Class A amp designed by Nelson Pass?
Looks like an interesting project, Erik! First order of business after you complete it, linear power supply: https://www.ebay.com/itm/150VA-DC24V-5A-Low-Noise-LPS-HI-END-Linear-Power-Supply-for-Audio-PSU/11299... Have fun with it! |
I think it was meant to bring the cost of the kit down to enable more people to experiment with the First Watt type circuit. The power supply in an amp is a significant part of the cost and increases the size of the chassis. In fact, I think the power supply is at least 50% of how good an amp really is. |
@dgarretson - the link to those 24V linear power supplies are just on the border of current requirements (5A). If you want a power supply with more current, you could look at one of these and ask them if they can make a 24V version. It would probably come out to be 24V at 7.5A of current. https://www.ebay.com/itm/New-TeraDak-DC-12V-15A-linear-power-supply/323443214646?hash=item4b4eb7c936 https://www.ebay.com/itm/High-Power-300VA-DC12V-15A-Ultra-low-noise-linear-power-supply-HIF-LPS-L14-62/123782483364?hash=item1cd202cda4:g:kf4AAOSwX09cm51~ The Hi Power (Zerozone) power supply is a lot more expensive, but it looks like it uses Nichicon FG caps inside. The Teradak probably uses Panasonic hi temp (105 degree). |
uhm, just a comment here. I haven't felt any of Erik's posts are offensive or "stirring the pot", including this thread. He brought up a topic of discussion, and even if he can't participate in the actual building of this kit, I don't think any of his comments are bringing down the spirit of what this topic was meant to do. |
@lewinskih01 - nope, I have not. It was just one of the few linear power supplies on ebay that did 24V at 5A (which is what the Amp Camp power switching supply is). I have tried a few different Teradak power supplies. I generally try to get a PS that has many smaller capacitors in the power supply to reduce ESR and provide a faster response to voltage draws. These have been for transports and HDMI video processing devices (such as Lumagen Radiance and a HDMI KVM switcher). The Teradak have done an excellent job at this. I suppose for the Class A Amp Camp kit, two large caps in that power supply would be just fine. |
@lewinskih01 - that's not really the best power supply here on ebay. You should search through all the Zerozone power supplies. I think those are usually the better ones for an audio device such as DAC or preamp because they usually have better capacitors (such as Nichicon Gold Tune or Nichicon Fine Gold FG). Such as this one: https://www.ebay.com/itm/Zerozone-Finshed-S130-Ultra-Low-Noise-DC-Linear-Power-supply-2-way-LPS-12V-... If you are looking to power an Audio PC, look at one of these (because they support all the voltages 3.3V, 5V, 12V): https://www.ebay.com/itm/ZEROZONE-4-Way-Low-Noise-Hifi-Linear-Power-Supply-DC3-3V-5V-12V-12V-L9-30/1... https://www.ebay.com/itm/TeraDak-high-power-850W-PC-ATX-Computer-linear-power-supply-output-3-3V-5V-... The TeraDak is for a full blown tower with a very high 850W capacity and full ATC motherboard connector and power cable chassis, but it is very expensive. |
@dgarretson - What Furutech connectors did you use? I don't see any DC connectors made by Furutech. The best I have seen is the Oyaide ones below: https://www.vhaudio.com/connectors-rcaxlr.html#OyaideDC But they are gold-plated, which slows down and warms up the sound. I chose the switchcraft ones because of this. As far as wire, I prefer pure copper (my preference) because silver can be a little to fast/sterile for me. I can't imagine trying to solder 10-11awg wire to these tiny DC connectors! lol. |
@dgarretson - you can test these Zerozone power supplies stock, but you can also upgrade the power cord and the fuse. In addition, I upgraded my DC output cables as well. I used a 5.5mm x 2.1mm DC plug from Digikey: https://www.digikey.com/product-detail/en/switchcraft-inc/767KS17/SC1389-ND/2238432 And 16awg UTP VH Audio cryo-treated OFC hookup cable w/ AirLok insulation below: https://www.vhaudio.com/wire.html#ofcairlok The results of the DC cable upgrade were significant. I kept the DC connector on the power supply side because it's hard to find the correct size replacement. I just de-soldered the existing cable and solder on my VH Audio wire. |
Even without break-in they improve on the stock Meanwell SMPS. Increased dynamics. Weighty and extended LF. I have found that going from switching power supply to a linear with a very large capacitor bank will yield significant improvements in bass strength and body. Along with all the other improvements! lol |
