[Scooba]

Quote:

Originally Posted by audionut /img/forum/go_quote.gif Anyone know of another source for the P-Channel PS mosfets 512-FQP3P50? Mouser is out of them until sometime in June. Digikey no go, too. Thanks for any info. Tommy

I have used MTP2P50EG as a replacement - Mouser part 863-MTP2P50EG . It works perfectly, and has the same pin assignment.
Or you can try here P-Channel Power MOSFET 3P50 500V 2.7A 85W 9.5pF (x4) - eBay (item 220437061984 end time Apr-13-10 17:43:13 PDT)

 

[audionut]

Quote:

Originally Posted by Scooba /img/forum/go_quote.gif I have used MTP2P50EG as a replacement - Mouser part 863-MTP2P50EG . It works perfectly, and has the same pin assignment. Or you can try here P-Channel Power MOSFET 3P50 500V 2.7A 85W 9.5pF (x4) - eBay (item 220437061984 end time Apr-13-10 17:43:13 PDT)

Thanks, Scooba. Those should work, like you said, as they have similar specs. Don't need 1 for my eXSTata, which is running fine, but I need one for that "other amp". It uses the same one in the - rail.

 

[Scooba]

You're welcome, audionut

.

As for the eXStatA, I've managed to make a quick listening session last evening at home, and I was not very impressed. But I think that my 404LE's need some burn-in (they have under 40 hours) . I don't know how much they will change in sound, but I hope they will

. For now, the sound is very fast and dynamic, but it lacks staging and depth .

 

[TimJo]

At bit off topic, but...

Quote:

Originally Posted by luvdunhill /img/forum/go_quote.gif I've gotten a few questions about the volume board that Beefy used in his build. I'm considering making a few more boards, but would like a few beta builders who are comfortable with SMD and willing to actually build the board in a reasonable time frame and offer feedback. I won't be able to build this version any time soon and there are are a few changes this go around that need to be tested. I'd be willing to provide a preprogrammed microcontroller, two PGA chips, and the board itself. If anyone would like to help, please PM me. Thanks!

I got my board and chips yesterday. Thanks Marc!

So now I just need a bom and a schematic, and I'll get started. Are those coming from you Marc, or is this BoilermakerFan?

 

[audionut]

Quote:

Originally Posted by Scooba /img/forum/go_quote.gif You're welcome, audionut . As for the eXStatA, I've managed to make a quick listening session last evening at home, and I was not very impressed. But I think that my 404LE's need some burn-in (they have under 40 hours) . I don't know how much they will change in sound, but I hope they will . For now, the sound is very fast and dynamic, but it lacks staging and depth .

Scooba, is this your first set of stats? Just curious, as my 404LE's have about the same amount of hours, and sound fantastic. Not sure how much stats need to burn in, compared to dynamics, but I do feel the amp needs a bit of time to settle in. Is yours the hybrid or SS?

 

[BoilermakerFan]

Quote:

Originally Posted by TimJo /img/forum/go_quote.gif At bit off topic, but... I got my board and chips yesterday. Thanks Marc! So now I just need a bom and a schematic, and I'll get started. Are those coming from you Marc, or is this BoilermakerFan?

Hopefully my board and chips show up today.

I have a partial BOM. I need to sort it out and make sure it's complete.

EDIT: My board and chip showed up.

 

[Scooba]

Quote:

Originally Posted by audionut /img/forum/go_quote.gif Scooba, is this your first set of stats? Just curious, as my 404LE's have about the same amount of hours, and sound fantastic. Not sure how much stats need to burn in, compared to dynamics, but I do feel the amp needs a bit of time to settle in. Is yours the hybrid or SS?

I had for a while a SR404 + SRM-006T II combo, sold it some time ago and bought the SR404 Limited . I also have a SR303 + SRM313 combo, borrowed from a friend, for testing purposes .
I'll try to explain what seems odd to me: if I compare the sound of individual instruments, the eXStatA + SR-404LE is by far the most detailed, dynamic and fast combo I've ever heard. But the spatial positioning of the instruments and singers is very weird (the guitars from "Krushevo" record form MA seem clearly positioned behind me) , and not very clearly delimitated .
I'll make more tests, and I've already identified a potential issue: I've forgot to connect the ground from the power-line in to the star ground point .

To be continued

!

 

[manaox2]

Quote:

Originally Posted by BoilermakerFan /img/forum/go_quote.gif Hopefully my board and chips show up today. I have a partial BOM. I need to sort it out and make sure it's complete.

I updated an old project list, but since then there are some revisions with this new board I believe, i will wait for luvdunhill to reply. One item is also back ordered and haven't found a suitable replacement for sure yet.

http://www.mouser.com/ProjectManager...sID=2782BA7937

EDIT: I also received my own board and chips! Thanks for the lightspeed shipping!

 

[Scooba]

Quote:

Originally Posted by audionut /img/forum/go_quote.gif Is yours the hybrid or SS?

I missed this question, sorry . My amp is the SS version.

I can say that the ground solved the staging/delimitation problem

.
Beside that, it seems that I have used a higher value for the BIAS. I lowered it, and lost the bright top end. I definitely need a meter with higher impedance

.

At this point the sound is excellent: fast, detailed, dynamic, yet rich and smooth. The timbres and textures of the instruments are very well presented. This is the first combo I heard that has this kind of performance.

Thanks to Alex for the design and support, and to Scott for the boards

.

 

[pabbi1]

Ok, I get 29 working builds.

Larry, did Bill get you sorted?

Beefy, any further enlightenment or mystery?

 

[Beefy]

Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif Beefy, any further enlightenment or mystery?

Power supply still buzzes for a few seconds on startup, but works perfectly after that. One driver my Lambdas still does funny things occasionally, but I have a set of NOS drivers incoming to fix this.

On the balance of things, it could have been easier...... a perfect storm of silly little intermittent issues is never fun. But I'm still very happy with the results

 

[HeadphoneAddict]

Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif Ok, I get 29 working builds. Larry, did Bill get you sorted? Beefy, any further enlightenment or mystery?

Not yet. Bill has been very busy lately.

 

[sachu]

Any builds here without a maxxed power supply?, i.e one with resistors instead of the CRDs in it?

 

[ericj]

Yeah, one of my power supplies lacks CRDs.

 

[HeadphoneAddict]

Quote:

Originally Posted by sachu /img/forum/go_quote.gif Any builds here without a maxxed power supply?, i.e one with resistors instead of the CRDs in it?

Quote:

Originally Posted by ericj /img/forum/go_quote.gif Yeah, one of my power supplies lacks CRDs.

Do you think maybe he wanted to also know more about how you liked it vs maxed, even if he didn't come right out and ask?

At least I am curious.