Hi
Thanks for all the feedback.
I now suspect that the mains input is to close to the RCA input. I will move it and report back.
As to the question why would one switch on a amp without it being hooked is simple. The amp was hooked up but the RCA made a poor connection and the buzz nearly took my ribbon speaker out.
Apart from the above problem the amp sounds fine.
Jozua
Thanks for all the feedback.
I now suspect that the mains input is to close to the RCA input. I will move it and report back.
As to the question why would one switch on a amp without it being hooked is simple. The amp was hooked up but the RCA made a poor connection and the buzz nearly took my ribbon speaker out.
Apart from the above problem the amp sounds fine.
Jozua
I'm glad you may have a solution Jozua.
Meanwhile, two further notes.
This thread is breaking our database, so once someone has claimed the 7000th post then I'm going to have to close it down and open a new one, and I'm getting my "B@st@rdised Krell" back on Thursday, so look forward to some interesting shenanigans with Class AB.
Meanwhile, two further notes.
This thread is breaking our database, so once someone has claimed the 7000th post then I'm going to have to close it down and open a new one, and I'm getting my "B@st@rdised Krell" back on Thursday, so look forward to some interesting shenanigans with Class AB.
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To all of you that have been along on this thread please check out the KSA-100 Board Thread just in case you need to build a larger version that produces ALOT more heat
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Mark
.Mark
For those who are interested, I'm selling my completed driver boards (Jan's layout) for $70. They are stuffed with Dale 1/4W resistors, Silver Mica, Elna Silmic and Panasonic FC cap's. Included are the output boards and two galvanized steel supports. I just don't find the time to finish the amp (to many projects going on).
Regards
Regards
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mpmarino said:I have a question that some may find annoying and elementary. If you feel that way, feel free to tell me to go pound sand and buy a book. It's OK, I'm going to buy the book anywayThe question is mostly for Stuart, but is general enough as well.
The ksa50 runs on ~40v rails. Stuart kicked it up experimentally to ~105 and developed a ccs(??) for the diff. ? I have dug thru the thread and can't find it, or at least any detail about it.
Is it possible to ramp the power up on this topology by simply giving the front end board it's +-40v with a small supply and running the driver and output on a (much) higher voltage, larger supply? Maybe I'm thinking wrong and the drivers should be at +-40 v as well, with the outputs at a higher voltage? Maybe I have no idea what I'm talking about and none are even a possibility (probably the latter
OK, should I get Self or Slone first?
D'uh.
Thanks,
Marc
Come to think of it, I too am waiting for Stuart's honeymoon to be over and he doing a white papaer on the 100vdc railed monster he made .
MP: Here's a low tech solution: Use 55v rails and bridge 2 channels... You'll get about 300 to 450wpc into 8 ohms depending on how large a PSU you use. Ofcourse the OP stages need to be enhanced accordingly, and I doubt if it will remain Class-A, but then you knew that.
You seem to be my type of guy... have a fire extinguisher handy when you do this... I will deny suggesting the above....
By the way Stuart, I am enjoin'in the SA-071's you sent me... Here's a prototype I made. Mids are open baffle, and I have since ditched the meshed mid.
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news...
Marriage cuts into diyaudio time thats for sure...
The parts of the big amp are out of the attic and awaiting the 'second' once over to see if anything got clobbered while they were stored. From what I can see so far things look pretty good.
I'm going to try and get to it over the course of the next weekend, SWMBO is out of town, and it's an ideal opportunity to make noise/smoke/sparks etc.
I'll think on the questions for a little while, I think I may have an answer to some of them, but not all at this point.
Stuart
Marriage cuts into diyaudio time thats for sure...
The parts of the big amp are out of the attic and awaiting the 'second' once over to see if anything got clobbered while they were stored. From what I can see so far things look pretty good.
I'm going to try and get to it over the course of the next weekend, SWMBO is out of town, and it's an ideal opportunity to make noise/smoke/sparks etc.
I'll think on the questions for a little while, I think I may have an answer to some of them, but not all at this point.
Stuart
Thanks!
I was planning to use the KSA-500 to run this. Currently a Krell KAV-250 powers the Mids/HF and a Forte Model 3 powers the SA-071's. I also have a couple of Luxman M-117's in bridged mode powering two JBL 15" subs separately... they do go loud when need be. But the thing I like is their imaging.
If I ever get the KSA-500 built, they might power the SA-071's, and then a Class-A version would power the mids and highs.
Since that pic was taken, I have replaced the Mesh mid (TAD origins but branded as Pioneer) with 2 XT-25's. So basically I will have a M-MH-T-MH-M arrangement with 3 XT-25's in the center, the middle one going from 12k-22k, the other 2 doing 2.5k to 12k and the PH-13's doing 400-2.5k and the SA-071's doing 60Hz to 400Hz.
I still have the CCS boards you sent me, plus all the parts needed, just no time to fit them.
Best,
I was planning to use the KSA-500 to run this. Currently a Krell KAV-250 powers the Mids/HF and a Forte Model 3 powers the SA-071's. I also have a couple of Luxman M-117's in bridged mode powering two JBL 15" subs separately... they do go loud when need be. But the thing I like is their imaging.
If I ever get the KSA-500 built, they might power the SA-071's, and then a Class-A version would power the mids and highs.
Since that pic was taken, I have replaced the Mesh mid (TAD origins but branded as Pioneer) with 2 XT-25's. So basically I will have a M-MH-T-MH-M arrangement with 3 XT-25's in the center, the middle one going from 12k-22k, the other 2 doing 2.5k to 12k and the PH-13's doing 400-2.5k and the SA-071's doing 60Hz to 400Hz.
I still have the CCS boards you sent me, plus all the parts needed, just no time to fit them.
Best,
damn, i just missed out on the perfect heatsink on eBay. ahhh well. anyone know a good place to get a proper fan tunnel that would be right for a 50-60 watt version of this amp? actually i'd really love to be able to get 75 watts but that wold probably require even more heatsink....so i'm not very set on 75 wpc.
