i think, that is the schematic posted on post#300[/QUOTE]
The schematic in post 300 does not have any part numbers.
OK guys, please put your names to the end of the list and we will manage to do it.
BYRTT 8 PCB set
CaféNoir 6 PCB set
ColinAlex 8 PCB set
DavorXXL 6 PCB set
DuffyDawg 4 PCB set + 4 SMPS400
electromf 4 PCB set
badrisuper 2 PCB set
volavola 2 PCB set
JethroTull 2 PCB set
kp93300 2 PCB set
momomo67890 4 pcb set
ua3grn 6pcb set
mj777 2pcb set
mkusan 2pcb set
Odysseas 4pcb (2 pairs)
hcbonfim 2pcb set
Albrerta 2pcb set
dw1narso 2 pcb set (1 stereo) + extra output device pairs & isolators (for stereo if possible)
supernet 2 pcb set
milandks 4pcb set
tjencks 2pcb set
quanghao: 2pcb set
audionootje: 4pcb set (2x stereo)
tritosine 4pcb (2 pairs)
Bobo le Chat 2 pcb set
AP2 2pcb set+2pcb empity (i need this also)
Meganinja 2 set ( stereo )
mikvous 2 pcb set
still4given 2 PCB set
Rick G 2 PCB set
kindhornman 2 boards
ravid 2 pcb set
evette 6 PCB set
siberia 2 pcb set
gnat 2 pcb set
potepuh 2 pcb set
metallicus69 4 pcb set
I hope I have not missed others. Thanks, LC
CaféNoir 6 PCB set
ColinAlex 8 PCB set
DavorXXL 6 PCB set
DuffyDawg 4 PCB set + 4 SMPS400
electromf 4 PCB set
badrisuper 2 PCB set
volavola 2 PCB set
JethroTull 2 PCB set
kp93300 2 PCB set
momomo67890 4 pcb set
ua3grn 6pcb set
mj777 2pcb set
mkusan 2pcb set
Odysseas 4pcb (2 pairs)
hcbonfim 2pcb set
Albrerta 2pcb set
dw1narso 2 pcb set (1 stereo) + extra output device pairs & isolators (for stereo if possible)
supernet 2 pcb set
milandks 4pcb set
tjencks 2pcb set
quanghao: 2pcb set
audionootje: 4pcb set (2x stereo)
tritosine 4pcb (2 pairs)
Bobo le Chat 2 pcb set
AP2 2pcb set+2pcb empity (i need this also)
Meganinja 2 set ( stereo )
mikvous 2 pcb set
still4given 2 PCB set
Rick G 2 PCB set
kindhornman 2 boards
ravid 2 pcb set
evette 6 PCB set
siberia 2 pcb set
gnat 2 pcb set
potepuh 2 pcb set
metallicus69 4 pcb set
I hope I have not missed others. Thanks, LC
My VSSA Ch1
Had just finished assembling one VSSA board, mounted to a massive heatsink. 3 holes had been drilled and threaded for the 2nd VSSA board. I used 2 Power-One HE-24-7.2A open frame regulated power supplies for the +24V and -24V. These I got from a surplus shop. When everything's done and tested, a better case will be assembled.
About the sound. Comparing to an upgraded Quad 303, there is a lot more bass from the same speaker that I used. It also went lower. The vocals are more detailed and clearer. The highs are also more pronounced and I can distinguished (due to the clarity) instruments better (crash cymbals,etc). It will only get better after it's burned in.
Hats off to you LC!
I don't want to go off topic since this is a VSSA with latFET thread but would like to ask if any of you guys had thought off or had started a VSSA with bipolar power output transistors?
Cheers,
WP
Had just finished assembling one VSSA board, mounted to a massive heatsink. 3 holes had been drilled and threaded for the 2nd VSSA board. I used 2 Power-One HE-24-7.2A open frame regulated power supplies for the +24V and -24V. These I got from a surplus shop. When everything's done and tested, a better case will be assembled.
About the sound. Comparing to an upgraded Quad 303, there is a lot more bass from the same speaker that I used. It also went lower. The vocals are more detailed and clearer. The highs are also more pronounced and I can distinguished (due to the clarity) instruments better (crash cymbals,etc). It will only get better after it's burned in.
Hats off to you LC!
I don't want to go off topic since this is a VSSA with latFET thread but would like to ask if any of you guys had thought off or had started a VSSA with bipolar power output transistors?
Cheers,
WP
Attachments
Not 100% on topic, but I hope, guys, you can help me out. I think this is my most obscure DIY moment. PSU 
is acting strange.
Last night I swapped from TSSA back to VSSA. I've got a unregulated , simple bridges and cap banks PSU from Sonny. On the bench everything is perfect. VSSA calibrates, offset trims. But when I connect VSSA to the speakers one channel is dead silent. Turns out one PSU channel swings all the voltage to the negative side. -65V and close to zero on the positive leg. And this is not the amp module fault. Modules swapped, same behaviour from same PSU side. Back to the bench. Perfect again. Back to the speakers. Same fault. And all this by the risk to burn my precious VSSA!
That really gets me sweating and my mind melting. I connect everything as per Lazy Cat's instructions. Moreover I had it connected some time before and it was working flawless!
is acting strange.Last night I swapped from TSSA back to VSSA. I've got a unregulated , simple bridges and cap banks PSU from Sonny. On the bench everything is perfect. VSSA calibrates, offset trims. But when I connect VSSA to the speakers one channel is dead silent. Turns out one PSU channel swings all the voltage to the negative side. -65V and close to zero on the positive leg. And this is not the amp module fault. Modules swapped, same behaviour from same PSU side. Back to the bench. Perfect again. Back to the speakers. Same fault. And all this by the risk to burn my precious VSSA!
That really gets me sweating and my mind melting. I connect everything as per Lazy Cat's instructions. Moreover I had it connected some time before and it was working flawless!
I'm glad you like your investment in VSSA.
For bipolar outputs drivers would be required plus thermal compensation to cancel out PTC.
Enjoy in music.
BYRTT 8 PCB set
CaféNoir 6 PCB set
ColinAlex 8 PCB set
DavorXXL 6 PCB set
DuffyDawg 4 PCB set + 4 SMPS400
electromf 4 PCB set
badrisuper 2 PCB set
volavola 2 PCB set
JethroTull 2 PCB set
kp93300 2 PCB set
momomo67890 4 pcb set
ua3grn 6pcb set
mj777 2pcb set
mkusan 2pcb set
Odysseas 4pcb (2 pairs)
hcbonfim 2pcb set
Albrerta 2pcb set
dw1narso 2 pcb set (1 stereo) + extra output device pairs & isolators (for stereo if possible)
supernet 2 pcb set
milandks 4pcb set
tjencks 2pcb set
quanghao: 2pcb set
audionootje: 4pcb set (2x stereo)
tritosine 4pcb (2 pairs)
Bobo le Chat 2 pcb set
AP2 2pcb set+2pcb empity (i need this also)
Meganinja 2 set ( stereo )
mikvous 2 pcb set
still4given 2 PCB set
Rick G 2 PCB set
kindhornman 2 boards
ravid 2 pcb set
evette 6 PCB set
siberia 2 pcb set
gnat 2 pcb set
potepuh 2 pcb set
metallicus69 4 pcb set
Ranchu32 2 pcb set
woofertester 2 pcb set
CaféNoir 6 PCB set
ColinAlex 8 PCB set
DavorXXL 6 PCB set
DuffyDawg 4 PCB set + 4 SMPS400
electromf 4 PCB set
badrisuper 2 PCB set
volavola 2 PCB set
JethroTull 2 PCB set
kp93300 2 PCB set
momomo67890 4 pcb set
ua3grn 6pcb set
mj777 2pcb set
mkusan 2pcb set
Odysseas 4pcb (2 pairs)
hcbonfim 2pcb set
Albrerta 2pcb set
dw1narso 2 pcb set (1 stereo) + extra output device pairs & isolators (for stereo if possible)
supernet 2 pcb set
milandks 4pcb set
tjencks 2pcb set
quanghao: 2pcb set
audionootje: 4pcb set (2x stereo)
tritosine 4pcb (2 pairs)
Bobo le Chat 2 pcb set
AP2 2pcb set+2pcb empity (i need this also)
Meganinja 2 set ( stereo )
mikvous 2 pcb set
still4given 2 PCB set
Rick G 2 PCB set
kindhornman 2 boards
ravid 2 pcb set
evette 6 PCB set
siberia 2 pcb set
gnat 2 pcb set
potepuh 2 pcb set
metallicus69 4 pcb set
Ranchu32 2 pcb set
woofertester 2 pcb set
Hi LC,
Thanks for the tips but can you please post a simple schematic on how this can be implemented, like the 1st schematic on this thread.
I do have several BC550C/560C, BD13916STU/14016STU and MJ15024/15025 transistors which can do the job.
As always,any help from the other gurus will be greatly appreciated.
Thanks!
WP
Thanks for the tips but can you please post a simple schematic on how this can be implemented, like the 1st schematic on this thread.
I do have several BC550C/560C, BD13916STU/14016STU and MJ15024/15025 transistors which can do the job.
As always,any help from the other gurus will be greatly appreciated.
Thanks!
WP
You might like to explore this thread: FET Hex and bipolar VSSA
There are several VSSA implementations, including bipolar output versions
Cheers!
Siberia try to connect VSSA to alternative PSU and be careful with GND connections.
i would also check the ground connection between the module and PSU. you might want to measure the voltage difference between the GND of the module and GND of the PSU, or more specific, put one Voltmeter terminal on a ground point of the VSSA PCB and the other one at the transformer central tap or at the first ground point between the ELCAPS (if you use separate rectifier for each supply rail). It's possible that the GND spade that needs three wires in the same point to have a loose contact... Or it might be something wrong in the PSU. Difficult to assess without PSU schematic.
Good luck!
Hi Metallicus69,
I'm really surprised that there is a lot going on the http://www.diyaudio.com/forums/solid-state/237219-fet-hex-explendit-amplifier.html thread. Really worth exploring.
Thanks,
WP
I'm really surprised that there is a lot going on the http://www.diyaudio.com/forums/solid-state/237219-fet-hex-explendit-amplifier.html thread. Really worth exploring.
Thanks,
WP
Still4given,
LC is good to his word from my experience. There is currently a supply shortage on the ALFET output device and I'm sure when they are delivered to him he will get on delivery of the remaining kits. BTW, based on my experience with the PeeCeeBee version it is worth waiting for. I still need to finance the SMPS and chassis for the official LC build, my kits are ready otherwise.
Jason Kuetemann
---------------------
When the student is ready the master appears.
LC is good to his word from my experience. There is currently a supply shortage on the ALFET output device and I'm sure when they are delivered to him he will get on delivery of the remaining kits. BTW, based on my experience with the PeeCeeBee version it is worth waiting for. I still need to finance the SMPS and chassis for the official LC build, my kits are ready otherwise.
Jason Kuetemann
---------------------
When the student is ready the master appears.
I'm going with PMI's power supplies for this. I already have the boards and tranny and the parts should be here any day.