Banned
Joined 2002
Don;t throw in the towel, Why are your fet leads soooooo long ? why not just mount them to the board like how they were designed to ? ( designed for small foot-print.
If you really want you can send both channels to me, and ill test and make it work.
J'
The FET leads are temporary...I will need to use them in the final assembly as the heat sinks are just a hair too short to mount the boards directly to them. I will trim them as necessary eventually.
Jase...I may take you up on that...I was messing around with the 9610's while I was still pissed off and ripped a pad off...it just keeps getting better...I should be able to salvage it - either that or I will have to mount the 9610's on the heat sink and run more wire...ugh...
I will CALMLY replace the rest of the 9610's since my last suspicion is that they are the root cause. Hopefully my mouser order arrives tomorrow...
I think tonight I will assemble the chassis and maybe mount the toroid, punch the holes for the RCA's, power, fuse, terminals etc...I shouldn't screw that up too badly...I need a small victory to keep me going...
Fred - thanks for the schematic...that may very well help trace down where the problem is further.
Jase...I may take you up on that...I was messing around with the 9610's while I was still pissed off and ripped a pad off...it just keeps getting better...I should be able to salvage it - either that or I will have to mount the 9610's on the heat sink and run more wire...ugh...
I will CALMLY replace the rest of the 9610's since my last suspicion is that they are the root cause. Hopefully my mouser order arrives tomorrow...
I think tonight I will assemble the chassis and maybe mount the toroid, punch the holes for the RCA's, power, fuse, terminals etc...I shouldn't screw that up too badly...I need a small victory to keep me going...
Fred - thanks for the schematic...that may very well help trace down where the problem is further.
Banned
Joined 2002
Banned
Joined 2002
OK...good night...started on the chassis...looking good so far. Once I get the boards sorted out they will mount to the bottom plate with some standoffs and the MOSFET's will get mounted directly on the heatsinks.
Nice chassis
looks nice, We should help you get the amplifiers working before you throw them into it tho, Easier to do when they are out not in,OK...yesterday I got one of the boards working!!! I replaced Q1,2,3 and somehow Z5 needed to be replaced too.
I hooked the other board up and there was some progress but I still need to troubleshoot. I replaced Q1,2,3 and I had about 9V across Z5 but when I checked R27 and 28 only one of them had voltage across - about 1.7!!! the other one had none...Hopefully I will get that sorted out today...
Progress finally!!!
I hooked the other board up and there was some progress but I still need to troubleshoot. I replaced Q1,2,3 and I had about 9V across Z5 but when I checked R27 and 28 only one of them had voltage across - about 1.7!!! the other one had none...Hopefully I will get that sorted out today...
Progress finally!!!
Done! Turns out R27 was fried...kept checking voltage and finally got around to checking the resistance and it was reading "1"...replaced with a backup 0.47 and the second board is up and running. WHAT AN ORDEAL!!!
Not sure what the root cause of all the failures but I'm glad I finally got it sorted out...
Now on to finalize the chassis - thanks for the help and encouragement!
Not sure what the root cause of all the failures but I'm glad I finally got it sorted out...
Now on to finalize the chassis - thanks for the help and encouragement!
Banned
Joined 2002
OK...more progress...
I have the chassis 99% done...I think I am just down to shortening the leads for the power FETs...
I spent this morning trimming the rest of the wiring and twisting all A/C runs...
The amp is very silent on my Universal Chip Preamp...Haven't tried it with the Aikido yet...and it sounds very nice...
The heatsinks were quite cool so I mounted another pair of 0.47 ohm resistors on the right channel. So it is now running about 2A bias and the heatsink is hot but I can hold my hand on it "indefinitely"...V+/V- is running now at a loaded 15V.
I have the chassis 99% done...I think I am just down to shortening the leads for the power FETs...
I spent this morning trimming the rest of the wiring and twisting all A/C runs...
The amp is very silent on my Universal Chip Preamp...Haven't tried it with the Aikido yet...and it sounds very nice...
The heatsinks were quite cool so I mounted another pair of 0.47 ohm resistors on the right channel. So it is now running about 2A bias and the heatsink is hot but I can hold my hand on it "indefinitely"...V+/V- is running now at a loaded 15V.
Banned
Joined 2002
Good work, Definatly shorten them fet wires, did you also short the input pins gnd to in- ? that will give you more input gain.
Also, try this, get a decent ( or test ) pot and make a passive volume control, this is what i do with my aleph mini's and i realized how much i am actually missing by using a fancy pre-amp with all the switches and gizmo's.
looks clean in the chassis, also ditch the regular speaker wire for rca connector hook up wire, get some shielded wire, If you don't have any, just get some rca cable or a old microphone cable it will be a-lot better and wont induce hums or noise.
Also, try this, get a decent ( or test ) pot and make a passive volume control, this is what i do with my aleph mini's and i realized how much i am actually missing by using a fancy pre-amp with all the switches and gizmo's.
looks clean in the chassis, also ditch the regular speaker wire for rca connector hook up wire, get some shielded wire, If you don't have any, just get some rca cable or a old microphone cable it will be a-lot better and wont induce hums or noise.
Yes, I was worried about hum due to proximity with input/output to the input voltage for the PSU...so far so good...it is very quiet. I have it hooked up to some Fostex FE127E eNabld in Fonken cabinets...about 90-91dB efficient.
Also, I am now listening with the Aikido preamp and the gain is a little more and sounds really sweet.
I have grounded the IN- to chassis ground...the gain is remarkable.
Also, I am now listening with the Aikido preamp and the gain is a little more and sounds really sweet.
I have grounded the IN- to chassis ground...the gain is remarkable.
Banned
Joined 2002
now try it with out a pre-amp and just make a passive volume pot
thats what i did, and love it.Noble pots / alps pots are cheap.
OK,
Weird thing, I replaced the input and output hookup wire with some shielded cable I had kicking around...belden microphone wire 2 conductor twisted with shield. I now have a fairly noticable hum/buzz coming from both channels.
Where is the best place to ground the -IN to? Should it go to the star ground location or can I run a short wire to the CHGND on the output?
I may try to reposition the toroid too...
Weird thing, I replaced the input and output hookup wire with some shielded cable I had kicking around...belden microphone wire 2 conductor twisted with shield. I now have a fairly noticable hum/buzz coming from both channels.
Where is the best place to ground the -IN to? Should it go to the star ground location or can I run a short wire to the CHGND on the output?
I may try to reposition the toroid too...
Banned
Joined 2002
Short in- to the gnd spot exactly beside it, there are 3 pins in a row for input,
in+ gnd in- short in- to gnd.
Allright...
I built an F5 from Peter's boards. I originally tried a 300VA 18V toroid and it was a little anemic - I then acquired a 600VA 18 toroid - a heavy mother...
So I transplanted the 300VA unit into the aleph mini referenced above. It is dead silent and all I can say is that I think it can shoop da whoop as good as the F5. I read about 390mv across the source resistors with .235 resistance.
The heatsinks are HOT...I read about 60C and could barely touch them for a few seconds. It sounds good enough to get a 3U case and use the 2U for a proper preamp case.
I built an F5 from Peter's boards. I originally tried a 300VA 18V toroid and it was a little anemic - I then acquired a 600VA 18 toroid - a heavy mother...
So I transplanted the 300VA unit into the aleph mini referenced above. It is dead silent and all I can say is that I think it can shoop da whoop as good as the F5. I read about 390mv across the source resistors with .235 resistance.
The heatsinks are HOT...I read about 60C and could barely touch them for a few seconds. It sounds good enough to get a 3U case and use the 2U for a proper preamp case.
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