colterphoto1 Posted December 30, 2006 Share Posted December 30, 2006 I have a nice clean HK430 receiver. I've known that it was a bit noisy since day one, so I always take the precaution of switching off the speakers when powering up/down. It is in my gallery and powers my Khorns. Because they are so efficient, I can barely hear the hum coming from the HK. Problem is, that now I'm bringing home speakers to audition and that is the easiest, cleanest room to set up and compare in. With some of these 88-92 db speakers, I can't get a good listening test in because of the bad hum. Yes it's 60 Hz, no it's not a grounded outlet, yes I've 180'd the plug to no real change in hum level. Could this unit need a capacitor refreshening or ?? M Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 30, 2006 Share Posted December 30, 2006 Michael, I have contemplated replacing the PS caps in my 430, and I think there are only about six in there that would need to be replaced. It wouldn't hurt, and these things ARE getting up in years. Bruce Quote Link to comment Share on other sites More sharing options...
Bill H. Posted December 30, 2006 Share Posted December 30, 2006 Michael, I've had three HK 430's.......and they all needed the caps replaced. I also was frustrated with the speaker wire connectors on the backs.....so that is why I sold them off........Great unit, but as was stated before, they are getting up in years......... Good Luck. Sounds exciting that you get to sample/test the new speakers! Congrats on getting the job that most of us dream about! Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 30, 2006 Share Posted December 30, 2006 How does one determine which caps need replacing? I've never tore into the inside of one, but I would imagine replacing all the caps would be rather expensive... Quote Link to comment Share on other sites More sharing options...
CONVERGENCE Posted December 30, 2006 Share Posted December 30, 2006 DR WHO QUOTE How does one determine which caps need replacing? I've never tore into the inside of one, but I would imagine replacing all the caps would be rather expensive... You have a point since old caps values are different than todays caps. For ex: They made 21MF caps back in the 80's now you only have 20 and 22 MF. That's why I would rather leave it to the pros like ALK. Anny way that should be the last thing to modify on a sound system. First thing should be speaker components conditions. ........................................... Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 30, 2006 Share Posted December 30, 2006 aye, but I know my caps are bad because the tuner section won't power up unless I leave it on for a very long time. Being in the electrical engineering program on my campus, I have no doubt that I can obtain the proper value caps (we have an entire store full of parts to our disposal) - and I like to think I know which side of the iron to hold (though some scars might say otherwise). [] I just couldn't imagine going to one of the labs and measuring every component one by one...talk about a lot of work. Quote Link to comment Share on other sites More sharing options...
CONVERGENCE Posted December 30, 2006 Share Posted December 30, 2006 I had mine repaired in mid 70's by Engineering dept.Cost me around 60$ . They corrected some manufacturer mistakes on top of that. Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 30, 2006 Share Posted December 30, 2006 The PS section on an HK 430 has, as I already mentioned, very few caps, and they are pretty obvious which ones. The larger electrolytics, are there in standard values. It wouldn't cost much to replace them, and then decide if you need to do others. Quote Link to comment Share on other sites More sharing options...
djk Posted December 31, 2006 Share Posted December 31, 2006 http://manuals.harman.com/hk/Service%20Manual/hk430%20sm.pdf When this amp was new, electrolytic values were -10%, +100% Just make sure the new ones fit, you may need to go higher in voltage (that's fine) and don't go higher than X2 of the original value in µF. Unit pops? C405 Gain is low/no bass? C408 (most likely), or C402 Scratchy volume control (on turn-on, OK after a few minutes)? C504 or C712 Hum (one channel)? C6, 7 or C8, 9 Hum (both channels, varies with volume)? C4, 15 Hum (tuner)? C3,4 Best bet? Like roaches, you got to get 'em all (the smaller caps are about $0.10 each in 25 lot from Mouser). Given the popularity of this unit, it makes sense to do a group buy and make up a kit of all values required. Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted December 31, 2006 Author Share Posted December 31, 2006 Ok, sound off- who wants to purchase a kit of these caps? I'll open mine up and get the values. Perhaps Doc or Trey could help me with the initial one. Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 31, 2006 Share Posted December 31, 2006 Two comments: First, with the addition of the service manual, we can build a list pretty easily. Second, Dennis can never die. He is too valuable a resource to lose. Thanks Dennis, this will help out tremendously.Bruce Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 31, 2006 Share Posted December 31, 2006 I'm interested Mike - I wonder how many parts will be common between the 430 and 630? Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted December 31, 2006 Author Share Posted December 31, 2006 and the 730 and the 930..... Quote Link to comment Share on other sites More sharing options...
Seadog Posted December 31, 2006 Share Posted December 31, 2006 I would be interested in three HK430 cap refresher kits. Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted January 2, 2007 Author Share Posted January 2, 2007 DOes anyone want to volunteer to create a parts list cross reference? A column for each HK in that series, rows with each Cap value... I'll make the purchase and sort them all out if someone can help with the legwork. M Quote Link to comment Share on other sites More sharing options...
DrWho Posted January 2, 2007 Share Posted January 2, 2007 hey Mike, that might make for a fun project if I'm ever down your way again...I forgot you had so many of the HK lineup! After we freshen em all up we can bust out your Colter Comparator and list minor sonic nuances if they exist. Maybe just for kicks we can do it on a few different types of speakers to see how consistent across the board it is. If only there were more time in the world... Quote Link to comment Share on other sites More sharing options...
wrench_peddler Posted January 7, 2007 Share Posted January 7, 2007 I would be interested in two sets for my 430's. What kind of $'s are we talking? Interest and $'s are directly proportional. Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted January 7, 2007 Author Share Posted January 7, 2007 if someone else wants to coordinate this, that's fine. I have a HK 430 and HK730 and could use a parts kit for each. I'll be off the Forum for a bit. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.