Recapping and repairing a Harman Kardon 730 twin power series stereo receiver

Here is a copy and pastable list to create a BOM for the phono board.
  1. log into your account over at Mouser
  2. click on the Accounts & Orders link on the right
  3. select BOMs in the drop down menu that appears
  4. click on the blue Create New BOM button
  5. click on the Copy & Paste option
  6. paste in the below info into the text area
  7. follow the upload process prompts
After reviewing the resultant list against @dlucy's list a few comments up, add it all to your shopping cart and you'll be able to purchase the components. After shipping and tax (I'm in North Carolina, so your result may vary?), I payed less than $25 for all of that.

647-UKL1E220MDDANATA 2
810-FG28C0G1H470JNT0 4
810-FG28C0G1H332JNT0 2
80-MMK5123J50J01TR18 2
647-UKL1A101MED1TD 2
647-UKL1V220MEDANA 2
505-MKS2C033301C00MI 2
505-MKS2C041001F00MI 2
505-MKS2C041001F00MI 2
647-UPW1E471MPD 2
512-KSA992FTA 2
512-KSC1845FTA 4
71-CCF555K62FKE36 2
71-CCF55100KFKE36 6
71-CCF55221RFKE36 6
71-CCF55-332K-E3 4
71-CCF55475RFKE36 2
71-CCF55-22.1K-E3 2
71-CCF553K92FKE36 2
71-CCF55100RFKE36 2
71-CCF5515K0FKE36 2
71-CCF55274KFKE36 2
71-CCF55121KFKE36 2
71-CCF5510K0FKE36 2
71-CCF55221KFKE36 2
71-CCF55680RFKE36 2
 
OK. I've been spinning vinyl all day today. @dlucy - the H/K - it's everything I wanted. It sounds great. I haven't heard another receiver yet that is as dynamic and has such great presence as the H/K. Doug asked me to comment on the phono mod that he did (see: https://audiokarma.org/forums/index.php?threads/modding-the-harman-kardon-730-phono-stage.769186/). My set up is a Dual 701/Stanton 881S --> H/K 730 --> KLH Model 6s. The 6s were recapped and foamed about a year ago. The first observation I had is that this thing is dead quiet - so much so that I now have to clean my vinyl before I play it (thanks, Doug). I've been A/B'ing the phono section with a Marantz 1060 phono that I'm using as a preamp into the H/K's amp section. I chose the 1060 b/c it has one of my favorite pre-amp sections (I'm just not crazy about the amp section). Beyond the slight Marantz coloration, sound-wise the phono sections are almost identical going through the same amp. The Marantz, as expected, is a little more polite and slightly colored (and I mean slightly) - maybe a little rolled off on top. The H/K straight up sounds more accurate and lively. Nice deep tones. Both have great sound stages and both deliver a nice timbre on stringed instruments. The H/K might go a little deeper, or might just be a little tighter on the bottom end. It definitely extends more on high end but w/o being fatiguing. They are very close. You'd really have to be listening hard to pick out the differences (or be a picky a-hole like me :D). Both are very musical and really enjoyable to listen too. I'm convinced that the H/K 730 amp section is magical. I love the forward, dynamic presentation it has. It really puts the music in the room. Overall, Doug's rebuilt H/K is a great sounding receiver and the phono pre is excellent (this is coming from a picky a-hole :D). It's exactly what I've been hunting for. I'm not going to compare it to a tube amp b/c it's not one, but it fills in nicely when I'm not listening to my tubes. It pairs really well with the Model 6s too. Next test will be using a tube pre (after I find one that I like. PAS2 w/Van Alstine mods anyone?). In the mean time, tho, I think I'll just hang and enjoy my new 730. It's pretty dang sweet on it's own. Well done, Doug! Now back to cleaning vinyl.

LPs tested:
  • Ray Lamontagne Ouroboros
  • Getz/Gilberto
  • Elvis Costello Imperial Bedroom
  • Muddy Waters Folk Singer
  • Phil Woods Warm Woods
  • Beatles Sgt. Peppers (of course)

Psychedelic music, where sounds are coming in and out of each channel, are really fun with the H/K. You can really hear the difference. The opening track of Sgt.Peppers, you can really hear them digging into the electric guitars in each channel. Very cool.
 
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Harman Kardon receivers back then really did sound good. They were they best sounding until we picked up the Luxman line and then the HKs were a great value for the money. The 730 listed for 100 less than the Lux unit (R-1040) and could be sold with a bigger discount because of a higher margin. The 330c, 430 and 730 are most excellent sounding units and available cheap today and not to bad to refresh. Probably the best values when you consider the inflated prices of the Pio/Mar/Sui/Macs out there now.
 
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I was trying some different cartridges today with the H/K 730. First, a Shure M75D with a Jico N75EJ/2. There's a really nice synergy between the two. It's very musical and detailed, but a little more rolled off than the Stanton. You lose a little of the energy and immediacy of the Stanton, but it's still a very musical reproduction. I also busted out my Pickering XSV 4000 with the original D4000 Stereohedron stylus. Oh my. The sound stage and energy are unmatched. The band is in the room with you. The 730 is a stud. \m/

Update: I'm really digging the Shure M75D with the H/K. As mentioned above, it's a little tamer than the Stanton/Pickering and you give up a little on the sound stage, but very balanced and musical. I'd say the phono pre is pretty sweet with any cartridge.
 
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@Flounder thanks for the review of the upgraded phono section. I got my parts in last week and will do the upgrade whenever I get a chance. See you in 10 years! LOL
 
I picked up an eBay HK 730 after reading the reviews on those units - I also have a HK 430 which was really nice sounding before my teenaged son blew it out one afternoon. Hoping to see some sonic improvement over my trusty Hitachi SR 604 (Which by the way is a really underrated unit) after the work is completed.
Went back and forth considering just being lazy and ordering one of the Outlaw RR2160’s -lots of power but in the end I could not get past that units appearance - also not keen on passing up the advantages of having a true dual-mono amplifier.
Anyway, this post is like an answered prayer, I’ve been slowly putting together my own list to refurbish my HK 730 and this just made my life a lot easier. I ordered the parts for both the refurb and the phono mods parts since losing the lower bass would kind of defeat the great frequency response of the HK and ruin the sound for me. I also ordered the VR’s and two sets of 100 transistors so I could match the hfe on them.
I especially appreciate you sharing your working knowledge about which are the best components to use, no way I could duplicate that, thanks Doug!
Ever consider putting together kits to do this work - eBay etc?
By the way, a BOM to update the HK 430’s or Marantz 2270 would be really cool also!
 
Yeah, it would be awesome to have a thread or subforum dedicated to just BOMs for all of the different amps, receivers, turntables, etc.
 
johkei said:
this just made my life a lot easier. I ordered the parts for both the refurb and the phono mods parts since losing the lower bass would kind of defeat the great frequency response of the HK and ruin the sound for me. I also ordered the VR’s and two sets of 100 transistors so I could match the hfe on them.
I especially appreciate you sharing your working knowledge about which are the best components to use, no way I could duplicate that, thanks Doug!
Ever consider putting together kits to do this work - eBay etc?
By the way, a BOM to update the HK 430’s or Marantz 2270 would be really cool also!
Click to expand...

Thanks for the kind words. I'm just paying back the AK'ers here and paying a bit forward. Glad you found it helpful.

Putting together a kit is a good idea and it would be far too much work for me for zero profit. Much better to provide a BOM and let people start with that. ;)

The hk430 is effectively identical, parts-wise, to the hk330c... except for the dual power supplies. If anyone ever has me rebuild a 430 for them, I'll make an accurate BOM from the work. Until then, look at my 330c BOM, compare to your actual insides, and make any minor changes. good luck!
 
Hi Doug,

Any chance you might have a board by board list of the parts you typically replace on these HK 730’s?
I purchased the parts you listed in your BOM and there certainly are enough components there.
I’ve been matching them by value on a spreadsheet but it certainly takes some time to figure out where they all need to go - especially when some of the values are updated! Thanks again for all your contributions.
 
johkei said:
Hi Doug,

Any chance you might have a board by board list of the parts you typically replace on these HK 730’s?
I purchased the parts you listed in your BOM and there certainly are enough components there.
I’ve been matching them by value on a spreadsheet but it certainly takes some time to figure out where they all need to go - especially when some of the values are updated! Thanks again for all your contributions.
Click to expand...

Hmmm... I'm not sure I follow your question. In the post with the list of parts or BOM for HK 730, the board is the very first column of info. Is that what you're asking for? If not, can you explain it a different way? I have a spreadsheet for all the recaps/rebuilds/restores and my posts here have most of those columns in them. I'm happy to help if I understand what is missing.
 
dlucy said:
Hmmm... I'm not sure I follow your question. In the post with the list of parts or BOM for HK 730, the board is the very first column of info. Is that what you're asking for? If not, can you explain it a different way? I have a spreadsheet for all the recaps/rebuilds/restores and my posts here have most of those columns in them. I'm happy to help if I understand what is missing.
Click to expand...
Hi Doug,

Sorry I did not see it the first time, exactly what I needed, thank you for clarifying that point.
I shall attribute this to a little apprehension from it being my Receiver project.
The old saying applies here “Better to remain silent and appear unintelligent than to speak and remove all doubt”
Thank you once again - great stuff!
 
johkei said:
The old saying applies here “Better to remain silent and appear unintelligent than to speak and remove all doubt”
Click to expand...

Nah, you did exactly the right thing: you asked a perfectly-reasonable question. That’s the best path to wiser. That’s the only way I’m even a little ways down that path....
 
dlucy said:
Nah, you did exactly the right thing: you asked a perfectly-reasonable question. That’s the best path to wiser. That’s the only way I’m even a little ways down that path....
Click to expand...
Thanks,

I did have one less goofy question, (I hope) I also ordered the full DLucey treatment parts that you recommended, and as you mentioned before, they were not on the BOM list.
In reading your other notes it sounds like the resistor's from that treatment should be going on the Tone control PCB?
Did you happen to have a location list for those extra components you normally install?
For example, I've been replacing some of the known noisy transistors you recommended but would feel better if there was a full list to check my own work against. Little things like the FCE on the transistors being different than the ones I pulled off the power amp PCB are giving me some mild apprehension, not because I doubt your work however, just my own.
Once again, you have done a lot to help and I do appreciate all that work.
 
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