Hi Valery,
Just an observation
I recall once you said to me, when reviewing my Mark Alexander CFA layout attempt, that my OPS devices were to close together. I see in that design shown a few posts back the OPS devices are no further apart than what I had done.
I recently made a small layout for a OPS and spaced the devices 40 mm apart, to match the pre-drilled holes for the DIYAudio universal HS spec. I was told, by another EE, that is too close as well, better to make them the next incremental size which would be 60mm.
Any comments or explanation?
Thank
Rick
Just an observation
I recall once you said to me, when reviewing my Mark Alexander CFA layout attempt, that my OPS devices were to close together. I see in that design shown a few posts back the OPS devices are no further apart than what I had done.
I recently made a small layout for a OPS and spaced the devices 40 mm apart, to match the pre-drilled holes for the DIYAudio universal HS spec. I was told, by another EE, that is too close as well, better to make them the next incremental size which would be 60mm.
Any comments or explanation?
Thank
Rick
I also was wondering about that but then again Simpelstark is not that powerful as the other Vallery / Jeff designs which were revised in the past for exactly the above reason, so I guess when smaller footprint of the board was chosen, the transistors thermal dispensation was tested and considered not a problem.
I'm so happy with my NS version I won't experiment with Simpelstark, it's up to Do to comment of it's sound, having built both.
I'm so happy with my NS version I won't experiment with Simpelstark, it's up to Do to comment of it's sound, having built both.
Hi Valery,
Just an observation
I recall once you said to me, when reviewing my Mark Alexander CFA layout attempt, that my OPS devices were to close together. I see in that design shown a few posts back the OPS devices are no further apart than what I had done.
I recently made a small layout for a OPS and spaced the devices 40 mm apart, to match the pre-drilled holes for the DIYAudio universal HS spec. I was told, by another EE, that is too close as well, better to make them the next incremental size which would be 60mm.
Any comments or explanation?
Thank
Rick
The Simpelstark amp uses two output pairs (one pair is drivers). In that configuration it's best to have them close together so their temperature is equal. In a three pair + layout the spacing needs to be increased to prevent the center devices from being super-heated by the rest of the devices which would cause current hogging.
I've also found in high power multi output layouts such as the Slewmaster or Modular NS amps it's best to keep the board length and the heatsink length close to the same. The outer two devices should be close to the ends of the heat sink so they won't receive extra cooling due to extra heat sink area.
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I've been able to finally listen to the amplifier on my ATS-4 speakers and it sounds really good!!! I've got this gnd loop issue with the SMPS (always an issue with those in pair, but when nailed properly, they're really good).
The vocals are quite amazing I would say. Didn't get a chance to deep dive but as soon as my PSU is noiseless, I will give them a good listening session and tell you more about my observations.
All the best!
Do
The vocals are quite amazing I would say. Didn't get a chance to deep dive but as soon as my PSU is noiseless, I will give them a good listening session and tell you more about my observations.
All the best!
Do
ok, found a way to make them totally silent! Both sitting on the same metal plate with large caliber cable added to earth on each SMPS to center point on metal plate and to jack earth. Seems totally silent this way. Max volume and nothing at all! Nice! Copper is a better conductor than aliminium so I'm pretty sure it is the path it takes. Electricity is like water, it will always take the path of less resistance..!
@maty tinman : Yes, Cresnet SMPS. They're really good SMPS but you really need to nail the grounding properly when using in pairs.
All the best!
Do
@maty tinman : Yes, Cresnet SMPS. They're really good SMPS but you really need to nail the grounding properly when using in pairs.
All the best!
Do
I have been following Cresnet developments for some years. I have tons of DC in mains so for a new amplifier I want to use SMPS. Hypex's are very expensive, low quality capacitors and they get too hot if they are to supply an appreciable amount of current.
Audio SMPS units for sale
And thank you again. I LOVE the expensive two Big Mundorfs M-lytics 47,000uF in one of my DC Blockers (the prototype). I took note of your very favorable comments on your USSA-5 class A amplifier (Canadian forums closed).
Audio SMPS units for sale
And thank you again. I LOVE the expensive two Big Mundorfs M-lytics 47,000uF in one of my DC Blockers (the prototype). I took note of your very favorable comments on your USSA-5 class A amplifier (Canadian forums closed).