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VSSA Lateral MosFet Amplifier

Bonjour
J'ai aucune données sur ce module , ni schéma , c'est difficile a juger de sa valeur musicale.
C'est tu un push-pull ou un SE ?
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Vous pouvez vous faire une idée en regardant le schéma de son petit frère moins puissant:
http://www.diyaudio.com/forums/vendors-bazaar/225747-vssa-lateral-mosfet-amplifier.html#post3285859
Il semble très apprécié, justement, pour sa valeur musicale. Classe AB, push-pull, Lateral mosfets, contre réaction de courant.

You can make your mind from its little brother:
http://www.diyaudio.com/forums/vendors-bazaar/225747-vssa-lateral-mosfet-amplifier.html#post3285859
Very well regarded for its musical quality, Class AB, push-pull of Laterals mosFETs, CFA.
 
Vous pouvez vous faire une idée en regardant le schéma de son petit frère moins puissant:
http://www.diyaudio.com/forums/vendors-bazaar/225747-vssa-lateral-mosfet-amplifier.html#post3285859
Il semble très apprécié, justement, pour sa valeur musicale. Classe AB, push-pull, Lateral mosfets, contre réaction de courant.

You can make your mind from its little brother:
http://www.diyaudio.com/forums/vendors-bazaar/225747-vssa-lateral-mosfet-amplifier.html#post3285859
Very well regarded for its musical quality, Class AB, push-pull of Laterals mosFETs, CFA.

Je préfèrerais en SE même si aujourd'hui ça ne se fait plus , sauf avec les tubes .
30 à 50 watts c'est suffisant pour moi ( HP full range 101 db )
VSSA ......... 3 étages ........... on peut faire plus court !

I would prefer SE to be even if today it is not done any more , except with the tubes
. 30 To 50 watts is enough for me ( HP full range 101 db )
VSSA ......... 3 stages ........... we can do more short!
 
Hi all,

I recently bought a few VSSA amplifier modules + enclosures. I read that the VSSA sound better with SMPS. The modules I bought are Jason's TO-3 and PMI's which I believe uses resistors as current sources.

Which SMPS would you recommend for a stereo VSSA able to drive 4 ohm speakers.

I was planning to buy one SMPS to power 2 channels, would the SMPS500QRv2 from Connexelectronic set to +/- 40Vdc be a good choice or would you recommend another SMPS.

Thanks in advance,
Eric
 
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Hi all,

I recently bought a few VSSA amplifier modules + enclosures. I read that the VSSA sound better with SMPS. The modules I bought are Jason's TO-3 and PMI's which I believe uses resistors as current sources.

Which SMPS would you recommend for a stereo VSSA able to drive 4 ohm speakers.

I was planning to buy one SMPS to power 2 channels, would the SMPS500QRv2 from Connexelectronic set to +/- 40Vdc be a good choice or would you recommend another SMPS.

Thanks in advance,
Eric
Hi Eric

We got better SQ with unregulated SMPS1200A180 or SMPS400A180 from Hypex, it looks regulation in Connex SMPS is messing too much with audio currrent sink/source.

Decide for yourself but now you know my recommendation.

L.C. ;)
 
I agree that dual mono is better when possible but power wise can a single SMPS400A180 power a stereo VSSA amp ?

Thanks,
Eric
Hi e_fortier!

One Hypex SMPS 400 is not capable to power 2 VSSA modules.

The number 400 states for music power of 400Watt, Hypex states that 1/8 of that power is RMS power, so 50 Watt.
Since single VSSA consumes around 25-30 Watt for bias current, two of them already brake the limit for continuous power. And this is without listening to music. So 2 SMPS400 are a must.

One SMPS1200 A180 should be enough since 1/8th of 1200 Watt is 150 Watt. So 50-60 Watt for constant biasing, the rest is available for music.

There are benefits when using one amp per power supply. But having more power has benefits too.

I tried one PS vs two PS on the First One amp module, you should do a search on the forum in this thread.
 
Hi e_fortier!

One Hypex SMPS 400 is not capable to power 2 VSSA modules.

The number 400 states for music power of 400Watt, Hypex states that 1/8 of that power is RMS power, so 50 Watt.
Since single VSSA consumes around 25-30 Watt for bias current, two of them already brake the limit for continuous power. And this is without listening to music. So 2 SMPS400 are a must.

One SMPS1200 A180 should be enough since 1/8th of 1200 Watt is 150 Watt. So 50-60 Watt for constant biasing, the rest is available for music.

There are benefits when using one amp per power supply. But having more power has benefits too.

I tried one PS vs two PS on the First One amp module, you should do a search on the forum in this thread.

Not really what datasheet tells us I think:

The SMPS400 is designed for music reproduction and is therefore not able to deliver its maximum​
output power long-term. The RMS value of any common music signal generally doesn’t exceed 1/8​
th

of the maximum peak power. The SMPS400 is therefore perfectly capable of driving the connected​
amplifier in clipping continuously with a music signal without the need of additional external​
cooling

Maximum output power smps400 is in there too, 600 watt. Maximum current 10A also.
 
Not really what datasheet tells us I think:

The SMPS400 is designed for music reproduction and is therefore not able to deliver its maximum​
output power long-term. The RMS value of any common music signal generally doesn’t exceed 1/8​
th

of the maximum peak power. The SMPS400 is therefore perfectly capable of driving the connected​
amplifier in clipping continuously with a music signal without the need of additional external​
cooling

Maximum output power smps400 is in there too, 600 watt. Maximum current 10A also.

Please read again my post and hypex data.

SMPS IS DESIGNED WITH MUSIC AMPLIFIER IN MIND. IT WILL WITHSTAND 400 watts short term, but not long term. In music signal of 400 watt there is only 1/8 of RMS power, so 50 watt continuous.
Since Vssa has output bias set pretty high, its continuous power consumption is 25 Watt. For two of them is double. This means that one smps400 is already on or beyond its longterm thermal limit.
 
Since single VSSA consumes around 25-30 Watt for bias current,
????
VSSA is set around 150mA for total quiescent current. And +-48V max = 96V at the rails.
This make 14.4W ( P= V*I) of iddle consumption. Witch is yet important. Where do you found those 30W ?
( I think you confused with F.O. modules, witch uses a pair in one chip as each output device.)

The max excursion on output is +-40V in the VSSA. This makes, on a single module , ~400W peak in a 4 Ohms load.
And ~200W with full scale sin waves.
 
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Please read again my post and hypex data.

SMPS IS DESIGNED WITH MUSIC AMPLIFIER IN MIND. IT WILL WITHSTAND 400 watts short term, but not long term. In music signal of 400 watt there is only 1/8 of RMS power, so 50 watt continuous.
Since Vssa has output bias set pretty high, its continuous power consumption is 25 Watt. For two of them is double. This means that one smps400 is already on or beyond its longterm thermal limit.

Hypex data for their 90% efficient poweramp into load with 1khz test tone, continuous, exceeds 50W powered by 50w PSU? I do not understand that, please explain.
 
????
VSSA is set around 150mA for total quiescent current. And +-48V max = 96V at the rails.
This make 14.4W ( P= V*I) of iddle consumption. Witch is yet important. Where do you found those 30W ?
( I think you confused with F.O. modules, witch uses a pair in one chip as each output device.)

The max excursion on output is +-40V in the VSSA. This makes, on a single module , ~400W peak in a 4 Ohms load.
And ~200W with full scale sin waves.

Just checked with LC on the phone. Esperado you are right.

Consumption for VSSA is 12.5 to 15 Watt. My VSSA was bought by a fellow friend and I do not have manual anymore, so I did some deduction from First One manual not realizing that there were more than one factors different (Current, Voltage, extra set of driver transistors).

On the other hand First One has standby consumption of 36 Watt per PCB. Just using the different Voltage I came to cca. 25 Watt. I use FO with 2 smsp1200A180.

It looks like one SMPS400A180 is enough if you do not intent to use maximum VSSA power for listening.
 
Hypex data for their 90% efficient poweramp into load with 1khz test tone, continuous, exceeds 50W powered by 50w PSU? I do not understand that, please explain.

Two VSSA use 30 Watt of constant standy power. It comes from SMPS, So SMPS is loaded with 30 Watt + 10% efficiency, so 33 Watt of standby power without playing music. This is 33 Watt of RMS power.

In the Hypex datasheet it states that SMPS400 is 400 Watt music power and only 1/8th of music power is true RMS power. SMPS can deliver 400 Watt on short term, on the long term SMSP400 is capable only 50 Watt. Delivering more power will overheat the SMPS and posibly make it fail?!?

At least this is how I understand their datasheet.