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Old 21st June 2010, 06:06 PM   #1561
Salas is offline Salas  Greece
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Quote:
Originally Posted by wushuliu View Post
No, I have no intention of modding with this board anytime soon, if anything I have another hypno and 2 mez boards that I can work on (prob the mez as I have multiple inputs).

No doubt, the performance of this design is euphoric. It's like going from really great well-produced cd to SACD version of that cd. Overall characteristics are similar to standard B1, but articulation and resolution bar is raised.

'Money' from DSOTM just gave me goosebumps...
The final BLUE edition board has the direct provisions for the two popular mods (film Vref caps, high CCS current ease) plus more and bigger filter caps, TO-220 diodes. But its not a big deal to do it with black boards too since you stashed away. Nice that you like it. Happy listening.
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Old 21st June 2010, 07:51 PM   #1562
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Quote:
Originally Posted by Salas View Post
The final BLUE edition board has the direct provisions for the two popular mods (film Vref caps, high CCS current ease) plus more and bigger filter caps, TO-220 diodes. But its not a big deal to do it with black boards too since you stashed away. Nice that you like it. Happy listening.
Thanks Salas, I will be getting the new board. My biggest grip about the black board hypno is the size of the holes. I bought a whole set of resistors that didn't fit or had to be forced through because the leads were too big (granted they were 1/2 watt, not 1/4 but the Dale 1/2w fit just fine). So I'm looking forward to some breathing space with the new board.

The only mod I may pop on this current board are the film caps, as I have a good amount between .1 and 1uf, including Jantzen Superiors, Dayton film/foil, ClarityCaps, and some PPS caps as well...
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Old 21st June 2010, 09:53 PM   #1563
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Well I've been searching but I can't seem to find a definitive post explaining the hot-rod process. Seems to involve increasing CCS via resistor value changes w/ R1?
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Old 21st June 2010, 10:05 PM   #1564
Salas is offline Salas  Greece
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Yes. Dropping the 68//68R down to about a 10R 5W resistor. That will need sinking the Mosfets, an easy way is to mount them down to the metal floor using insulation pads. There are posts and even reviews of before/after by members. I guess I will have to do a concise recap at a point soon along a BLUE BOM.
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Old 21st June 2010, 10:56 PM   #1565
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Yes. Dropping the 68//68R down to about a 10R 5W resistor. That will need sinking the Mosfets, an easy way is to mount them down to the metal floor using insulation pads. There are posts and even reviews of before/after by members. I guess I will have to do a concise recap at a point soon along a BLUE BOM.
Great, thank you. I found some before/after reviews, just not a straight this-is-how-you-do-it. Recaps are always nice
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Old 22nd June 2010, 05:26 PM   #1566
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It seems to be hard to find unmatched 2sk170bl's here in the US. The only source I found was Amplab's 20pcs for $26. I would go for that if I knew I could get the 4 matched Idss as well. It would cost just as much to get Blues' matched fets and unmatched fets from that guy in HK (or Ebay). Not to mention I'd have extras for any additional builds.

Is there a good chance I would get 4 close enough Idss out of 20pcs?
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Old 22nd June 2010, 05:43 PM   #1567
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Originally Posted by wushuliu View Post
It seems to be hard to find unmatched 2sk170bl's here in the US. The only source I found was Amplab's 20pcs for $26. I would go for that if I knew I could get the 4 matched Idss as well. It would cost just as much to get Blues' matched fets and unmatched fets from that guy in HK (or Ebay). Not to mention I'd have extras for any additional builds.

Is there a good chance I would get 4 close enough Idss out of 20pcs?
Yes there is. You will need a total of 10x 2SK170BL. I bought 20 too, and had a VERY close matching. I have my matching paper here, my 2 closest ones were:
IDSS:
-8.365mA and 8.362mA

-6.872mA and 6.884mA

Far closer than what we need here. Keep the unmatched for the shunt part of the circuit.
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Old 22nd June 2010, 05:54 PM   #1568
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Originally Posted by regiregi22 View Post
Yes there is. You will need a total of 10x 2SK170BL. I bought 20 too, and had a VERY close matching. I have my matching paper here, my 2 closest ones were:
IDSS:
-8.365mA and 8.362mA

-6.872mA and 6.884mA

Far closer than what we need here. Keep the unmatched for the shunt part of the circuit.
Brilliant. Thanks reg.
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Old 23rd June 2010, 03:46 AM   #1569
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Are there any recommended heatsinks for the IRFPs that would be good for hot-rodding?
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Old 23rd June 2010, 08:21 AM   #1570
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The DCB1 is laid out specifically to allow any size of heatsink to be attached to each pair of FETs
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