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VSSA Lateral MosFet Amplifier

As you all probably know my demo VSSA amp has original Hypex SMPS400A180 power supply installed, simply because of better sonic quality compared to linear PSU. But original SMPS had SAMWHA elcos all-over PCB, so I made some measurements before and after and got significantly better results when re-caped all elcos with Panasonic. Since SMPS is unregulated (emulates linear PSU) voltage drop at constant 5 A (8 Ohm load on PSU output) is now only 2 V, before 3,5 V, and ripple 1 Vpp, before 2,5 Vpp, also 100 kHz switching carrier as ripple is now only few mV. Tomorrow these new SMPS-s will be installed in demo unit and sound check will follow.

BTW next week I expect to get the first batch of ALF mosfets (around 50 pcs,) so quotations and deliveries will consequently start as planned.

Hey Andrej, do you have a sound check for HYPEX PSU, SAMWHA verse Panasonic ELCOs for report/learn us audio freaks.
Also the earlier comparisation between linear verse smps could be relistened with total same equipped pcb's and total same cabling (both internal and external cabling), which they was'nt at the time of test and would be more fair i think.
But please don't feel pressure, cause you also have right to have a life and some relaxing. Then i must do it myself later when pcbs arrive and i get hold on PSUs. At the moment i plan to start with classic linear, and smps later when money would allow.

Ricky
 
Dear VSSA GB members

Yes, of course you can make the payment to PayPal account: esl@siol.net

In this case add extra 5% to the Total Price amount in the Proforma Invoice.

But please, do not forget to state Proforma Invoice number and your name, just to know exactly from whom the payment came. ;)

Regards,

Andrej

You've got money :D

I keep hearing about Connexelectronic (with whom I have a PSU on order for my JLH project since April 8 and have had zero communication from) and the other company that is more expensive. What company is this other company and do they actually deliver in a reasonable amount of time?
 
You've got money :D

I keep hearing about Connexelectronic (with whom I have a PSU on order for my JLH project since April 8 and have had zero communication from) and the other company that is more expensive. What company is this other company and do they actually deliver in a reasonable amount of time?

The other company I had on my mind is ColdAmp especially SPS30 regulated SMPS suitable for VSSA. A little bit expensive but probably the best encountered so far. :up:
 
Hey Andrej, do you have a sound check for HYPEX PSU, SAMWHA verse Panasonic ELCOs for report/learn us audio freaks.
Also the earlier comparisation between linear verse smps could be relistened with total same equipped pcb's and total same cabling (both internal and external cabling), which they was'nt at the time of test and would be more fair i think.
But please don't feel pressure, cause you also have right to have a life and some relaxing. Then i must do it myself later when pcbs arrive and i get hold on PSUs. At the moment i plan to start with classic linear, and smps later when money would allow.

Ricky

I already expressed my feelings about SMPS400A180 upgrade with Panasonic elcos in post #1053 :up:

So far the best possible PSU to supply single VSSA channel and it is uncomparable with linear PSU, so much better. Current on demand - always there when needed.

Tune-up of SMPS400A180 as follows:
- 820 uF/200 V SAMWHA replaced with 1500 uF/200 V Panasonic EE
- 100 uF/100 V SAMWHA replaced with 220 uF/50 V Panasonic FR
- 10 uF/100 V SAMWHA replaced with 47 uF/63 V Panasonic FC
- 4,7 Ohm NTC shorted after 2 s from power-up
- PSU connection wires soldered directly

Mid-range presentation lively realistic, enormous energy in low-range, even more transparent and controlled bass. :yes:
 

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I received invoice and will pay tomorrow :)

As I can't find anything specific about the heatsinks, how circa big should it be when using fans to cool it? I need to make a little more room for PSU and phono pre-amp, so fans look like good idea to cool the VSSA :)

Type and size of the heatsink depends on its surface area and dissipation capacity stated in manufacturers specifications. As long as it is 0,5 K/W or less it is fine. Fan forced cooling should results to the same 0,5 K/W thermal dissipation capacity. So all be careful to use proper heatsink or fan cooled one. :cool:
 
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VSSA GB Info

Dear VSSA GB members :wave:

All 85 Proforma Invoices sent to yours e-mails. ;)

I will proceede with VSSA PCB set deliveries only to the GB members who paid the correct amount stated on the Proforma Invoice. :yes:

Please state Proforma Invoice number and your name on payment form, just to know exactly from whom the payment came. :up:

Regards, Lazy Cat :cheers:
 
New Streamer-DAC still not in Anagram Streamer-DAC (picture) league which I own from before. Still few modifications ahead to be done to even come close or maybe not at all. :rolleyes:

Stream unlimited has a Unit based on microchip/SMSC jukeblox.

It is an arm9 with an seperate audioengine (hardware) where abc-pcb which is not anagram has a media renderer based on DSP from analog devices.

I suspect that the DSP is more powerfull than the audioengine.

The latest firmware adds dsd playback.
 
Stream unlimited has a Unit based on microchip/SMSC jukeblox.

It is an arm9 with an seperate audioengine (hardware) where abc-pcb which is not anagram has a media renderer based on DSP from analog devices.

I suspect that the DSP is more powerfull than the audioengine.

The latest firmware adds dsd playback.
Versatility of streaming module means nothing to me if there is not a bit-perfect HR WAV stream assured and by NMR module that is for sure. OEM NMR module is widely spread in many high-end audio network players and its quality is unquestionable.

Software integration and implementation can be adopted to the manufacturers specific needs and most likely the code is the only limit here.

To me that is irrelevant and the only importance here is a raw streaming itself and the quality of the DAC which follows I2S or S/PDIF signal, completely different story, although ...
 
Well . We do not agree on this subject. Lets take it in another thread.

But basicly the software implementation is very important. If not the most important part. If there is the smalest gab in code, or a wrong implementation of the decode you will hear it right away. It is difficult to move the code from one platform to another without the need to modify the code..

Thats all for now.