Ok so I got it tested on some speakers and I'm just floored at the sound of this thing. Although I am trying a new to me adcom gfp750 at the same time. My speakers are b&w 683 and I'm using an iPod as the source I even have mismatched rca cables going from the adcom to the B&k amp. I bought a spool of the Belsen 89259 cable and 200 canare crimp on rca plugs. I'm all set to start making some cables up, it would be interesting to see if the good cables make a difference or not. Definitely a great sounding set up though. Those amps are gems for the price they can be had for.
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Congratulations on the great sound for pennies on the $.
I usually change all the e-caps on funny sounding audio equipment without thinking too hard, but I've been driven out of organforum for telling people to do that. Now run by proponents of "replace only the part that is bad" club. professional repairmen that want the call. '
I now like those gold plate RCA cables salvage from TV sources. Come in triples, a red, a green, and a blue. $2 at Salvation Army resale.
I usually change all the e-caps on funny sounding audio equipment without thinking too hard, but I've been driven out of organforum for telling people to do that. Now run by proponents of "replace only the part that is bad" club. professional repairmen that want the call. '
I now like those gold plate RCA cables salvage from TV sources. Come in triples, a red, a green, and a blue. $2 at Salvation Army resale.
Dear all, I know this is a old thread but does someone know the difference between the EX4420 and the M version?
I have seen a few pictures where the M version looks like a regular stereo amp.
Does the M version run both channels in parallel?
Would be very happy if some one can tell as I can buy a EX4420M version for not to much money and hope to convert it to stereo if possible.
Best regards, Veeren
I have seen a few pictures where the M version looks like a regular stereo amp.
Does the M version run both channels in parallel?
Would be very happy if some one can tell as I can buy a EX4420M version for not to much money and hope to convert it to stereo if possible.
Best regards, Veeren
They are almost identical except the front end is on only one of the boards. All of those parts are left out of what would be the second channel. The second channel is basically the drivers and the output stage. The outputs are strapped parallel with wires ran from the other side. I have a mono 4420 that works fine if I unplug the second board basically a single channel of a stereo amp. When I plug in the second half of the amp, when turning up and setting the bias as per factory instructions the 1khz signal goes flat and something very wrong happens. It’s been a while since I looked at it but it’s like something happens to one of the voltage rails. It works flawless without the additional output stage attached so it’s got to be something on that board. I’ll get it out for a look soon and see what i have to do to fix it. You should be able to turn it into a stereo amp by changing a little bit of wiring and adding the missing components to the second board. I do have a B&K 200.7 and a 200.5 as well to checkout. Before I get to those I need to find a fault in one of my all time favorite sounding piece of gear. My mother had a Harman Kardon PM-655 integrated amp that just amazed me every time I turned it on. Well I found the next best thing the PM-665 that has two power transformers as an upgrade and a few other things additional. I can’t wait for that one. I think it just needs the capacitors replaced as there are a couple that are bulging.
Thanks Royxc800, I hope you will get yours fixed.
I had a HK 650 once that would lower its volume and then switch of, never thought of looking at the caps, I was not aware they would go bad that quick!
Having worked mainly with European brands with European parts I never had to suspect them before.
I have a old Philips portable radio from the seventies that still works fine but also a Philips scope from the eighties where many of those blue Philips e-caps are gone go figure!
I remember Sprague caps and others from the US being very good by reputation, they must have been to expensive for HK.
Best regards
I had a HK 650 once that would lower its volume and then switch of, never thought of looking at the caps, I was not aware they would go bad that quick!
Having worked mainly with European brands with European parts I never had to suspect them before.
I have a old Philips portable radio from the seventies that still works fine but also a Philips scope from the eighties where many of those blue Philips e-caps are gone go figure!
I remember Sprague caps and others from the US being very good by reputation, they must have been to expensive for HK.
Best regards
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