TBPO my Control PCBs were a bit on the large size and the transistors had to be opened up to fit their larger footprint.
The best thing to do is to save the PCB image and then use MICROSOFT WORD to print the image. It's an easy job to resize it until the spacing for the component leads is correct. Once correct just print it onto Acetate sheet and you are ready to go.
Anyone know where I can get some plastic end caps from, to blank off the fixing holes in the heatsinks. I was thinking along the lines of what they use in tubular furniture.
I think it looked better in ZINC GREY but it needed to be black to shed the 400W of Class A heat.
I'm not sure if it is me or the amp.
The Aleph 4 is certainly a very BRIGHT amplifier. So BRIGHT in fact that I feel that I am hearing a lot more sibilance that I ever heard on my A700.
I'm currently listening to QUEEN and Freddy certainly has more TZZZZ than I am used to.
CHER was equally sibilant.
Maybe the amp needs dulling a bit with the very bright B&W 683s ?
The Aleph 4 is certainly a very BRIGHT amplifier. So BRIGHT in fact that I feel that I am hearing a lot more sibilance that I ever heard on my A700.
I'm currently listening to QUEEN and Freddy certainly has more TZZZZ than I am used to.
CHER was equally sibilant.
Maybe the amp needs dulling a bit with the very bright B&W 683s ?
I would hesitate calling an Aleph amp bright, and I have built quite a few. I have very ruthless Seas Thors and sibilance has never been a problem. I would be looking elsewhere for the problem.
Best, Bill
Best, Bill
The bass is stunningly powerful and tight. The low mids good and well defined. It is just the TSSSSSS from almost every recording that I have tried so far.
I'm listening to Elvis at the moment. Still the same.
The A700 didn't have that problem with exactly the same source and speakers.
I'm listening to Elvis at the moment. Still the same.
The A700 didn't have that problem with exactly the same source and speakers.
Is it normal to hear TSSSS after most (sung) syllables ? It's not there after a tambourine ring or a piano note.
& for fun!
How else would you suggest mounting them. They were supplied as coils of wire with no mounting arrangements.
I could "pot" them with a steel nut and then bolt them to the bottom of the chassis.
There isn't enough "Real Estate" to lie them down.
Suggestions are always welcome to improve the project.
The big washers by the way are plastic. I appreciate that the steel bolts will become magnetised in time, especially with 2.4A passing through quite a few turns of coils.
I could "pot" them with a steel nut and then bolt them to the bottom of the chassis.
There isn't enough "Real Estate" to lie them down.
Suggestions are always welcome to improve the project.
The big washers by the way are plastic. I appreciate that the steel bolts will become magnetised in time, especially with 2.4A passing through quite a few turns of coils.
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Hello from Downunder!
Good God ... I logged-on today having been invited to this thread and was informed I last logged-on in May 2009 !!!!!!
I would agree with Bill - I too have built a few of these and it is not an over-bright amp ... quite "warm" if anything. You may have some short/damage/unseen issue if this is really the case ... and alas, it may be bloody hard to find.
Is it the same on both channels, listening to same source mono mode?
If you can get a CRO and signal generator square-wave responses might give you a hint of underlying mischief.
If your only weapon is a cheapo MM, then start at point 'a' on the circuit diag and compare R<>L channels looking for disparity all the way to the end.
You may have damaged more than you realised in the recent misadventure.
Cheers,
Mark
PS: Love the hardware ... now that's an amplifier ...
Good God ... I logged-on today having been invited to this thread and was informed I last logged-on in May 2009 !!!!!!
I would agree with Bill - I too have built a few of these and it is not an over-bright amp ... quite "warm" if anything. You may have some short/damage/unseen issue if this is really the case ... and alas, it may be bloody hard to find.
Is it the same on both channels, listening to same source mono mode?
If you can get a CRO and signal generator square-wave responses might give you a hint of underlying mischief.
If your only weapon is a cheapo MM, then start at point 'a' on the circuit diag and compare R<>L channels looking for disparity all the way to the end.
You may have damaged more than you realised in the recent misadventure.
Cheers,
Mark
PS: Love the hardware ... now that's an amplifier ...
PS: I would have sympathy for the suggestions of (1) finding more ventilation above the amp, i.e. get it out from the current location under the TV, (2) cutting adequate vent holes top and bottom of the chassis to reduce internal T and (3) finding another mounting arrangement for the chokes.
There's no top on the amp at the moment and it is running fairly cool. I do have full 'Scope and sig. gen. What do you suggest ?
It's been running at reasonable volume (4W or so) for over 40 Hours now, any semiconductor damage, I would have thought, would have manifested itself by now.
Heatsinks are remaining at about the 50-60 degrees mark.
Heatsinks are remaining at about the 50-60 degrees mark.
It might look tight in its confinement but the fins on all sides have clear ventillation and heat is not a problem.
If the Chokes have become magnetised could that be the problem in the CLCC configuration.
Nelson doesn't use them, I might just try running the same CCC configuration that I did with the A700. It worked fine with that amp.
If the Chokes have become magnetised could that be the problem in the CLCC configuration.
Nelson doesn't use them, I might just try running the same CCC configuration that I did with the A700. It worked fine with that amp.
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