Recent content by KeyserSozee

Hello all, after recently working on one of these (with problems in the LCH amplifier), I have uncovered how to adjust the Luxman L435's bias. This is an adjustment for the quiescent current (idle current), and is adjusted by using VR7101 / VR7102. The test points (which aren't labeled), and...

The cap in your picture RA is a 560pf polystyrene, you can see that it says '561J' on its side. The 'J' signifying a 5% value tolerance. I would now also like to apologize for hijacking this thread lol

Like suggested by Hyperion, you'll still have to read and go by the parts in your exact unit. From my experience all of the polystyrene caps you're referring to are marked the same way film caps are (Eg. 101 = 100pf, 471 - 470pf, 153 = 0.015uf, etc..). I personally wouldn't replace these though...

That's quite unfortunate, when was the last time this amplifier was serviced? It is long overdue.... How comfortable are you peeling the bottom off and probing around? I'd start by checking power supply voltages. At the very least a good visual inspection of the insides might point to...

Nice job, very well done.... the 4x pots on the PSU / EQ board can be adjusted without removing the circuit board from its mounting location. There are small holes through the circuit board to allow a (very small) screwdriver to be inserted from the back, adjusting the pot from its 'bottom'...

I've always had to read his posts a few times to really truly understand them lol ughhhhh... The online audio community (and McIntosh community especially) have lost one of their greatest resources.

I'd suggest testing from the power supply down towards the driver boards... I assume the caps in the PSU are still original? Or since you seem to have isolated it to a particular driver board, go over it a few times and check your work. Make sure there aren't any disturbed/broken traces on...

Any updates? :cool:

I figured this problem out and posted the results two posts above ...and it was a pretty simple/dumb fix in retrospect. Thanks for your insight though, much appreciated,

Yes rBuckner, usually a higher voltage capacitor will have slightly less ESR than a lower voltage one... but I'm not going to install a capacitor 100v over the tolerance needed just to have 0.05ohms less ESR, the difference in ESR between it and the proper voltage capacitor is negligible. There...

A lot of good info there... as far as modern capacitors being 'pretty robust' though, that's a little misleading. In my experience modern capacitor voltage tolerances (especially electrolytics) are VERY strict. A modern 50v cap would NOT tolerate regular spikes around 55-60v for very long at...

In vintage gear engineers were often limited by the physical size of components. So now some people (who understand circuits/with enough experience) will increase the capacitance in certain locations for different reasons. It's a popular thing to do in a power supply (where most of the bigger...

Patrice is right, that pin is supposed to be grounded ...but it usually is grounded from the underside of the socket, which I'm sure it still is. There's an empty solder lug directly above your broken terminal strip (visible in your photo), that grounds the meter lamp circuit. I'm not sure...

Yes, c_dk is right ....that would be the proper way to do it. Think you could pull the curtain back a little more on how that is done exactly? Pretty please, with a McIntosh apple on top?

CaptFantastic is known to replace pictured parts with lower quality ones without notice ...so I wouldn't be surprised if you got a different/lower quality pot in the mail from him. The only reason I would ever buy anything off of him (and I have a few times), is when I can't get a replacement...