You can spot an early 1970’s Harman Kardon from a mile away. This top-of-the-line Harman Kardon 930 is no exception. The blackout dial face, classic green dial lighting, brushed aluminum bottom panel and red illuminated power button make it a very distinctive receiver. It was introduced in 1972, with an MSRP of $399.95, and produces a very conservative 45 watts per channel. The other receiver in the x30 series from Harman Kardon was the 30 wpc model 630. The 630 and the 930 were followed by the 430 and the 730 in 1976.
The 930 has some chrome plating in places and the knobs are machined metal. It’s later replacement, the 730, had a thick foil covering the face plate and plastic knobs with metal caps.
The signal and tuning meters leave a little to be desired as they are fairly small and hard to see.
The Contour switch, similar to a loudness switch, is used to compensate for the Fletcher-Munson effect. What? You’ve never heard of the Fletcher-Munson effect? Well, human hearing loses sensitivity to the lower frequencies as volume is reduced. This makes listening to music at low volume sometimes feel thin. Activate the Contour switch and the lower frequencies will get a boost relative to the high frequencies. This gives the music a more full sound at lower volumes.
The tone controls are two piece (dual concentric) knobs. You can adjust the tone for the left and right speakers independently. The outer knob adjusts the left channel and the inner knob adjusts the right channel. The three push button switches to the right of the tuning knob are the FM muting switch, MPX Filter switch and the Stereo Auto switch. The Stereo Auto switch allows you to listen to a poor FM signal in mono rather than stereo. The button should normally be depressed to listen to FM in stereo.
The Mode control is interesting too. It switches between stereophonic and monophonic operation depending upon the source. REV will reverse the left and right channels. STEREO is normal stereo. L+R combines the left and right channels. L sends the left channel signal to the left and right channels and R does the same for the right channel.
The HK 930 really looks nice in the optional wood case. You don’t see too many with the wood case. Another cool aspect of the Harman Kardon 930 is that the dial scale is lit when AM or FM is selected but goes dark when any other source is selected so it is less of a distraction.
Specifications:
- Tuning range: FM, MW
- Power output: 45 watts per channel into 8Ω (stereo)
- Frequency response: below 4Hz to above 70kHz +/- .5 dB
- Total harmonic distortion less than 0.5%
- Damping Factor: 30 or better to below 20Hz
- Input sensitivity: 1.5V
- 2 Phono inputs
- 2 Tape inputs
- 2 Aux inputs
- Dimensions: 432 x 121 x 350mm / 17 x 13 3/4 x 4 3/4 inches
- Weight: 13.2kg / 29 lbs
- Year: 1972
Under the 930 logo on the front panel you’ll see the words Twin Powered. This means that the 930 has dual power supplies. One for each channel. Notice the two large transformers in the above picture. It’s essentially like having a mono amp for each channel. The two transformers also make the HK twin powered receivers heavier than they look. I believe the HK 930 was the first solid state receiver to utilize dual mono amps in its design. Notice the four large 6800 mfd filter caps as well.
The dual power supply amp design is claimed to add more imaging and dynamics to the sound. Some original reviews stated that at low power output the difference is not that noticeable but that at higher power levels the dual amp design really begins to shine, especially with more dynamic source material.
In the 930, Harman Kardon utilized their famous ultra wide band frequency response circuitry and a 4-gang tuner. It uses a FET for the first of its two r.f. amplifiers. Overall, the FM tuner is pretty good but is not the 930’s strong point.
The power amp and pre-amp sections are separate so you can use an EQ if you want. Jumpers on the back of the unit connect the power and pre amps. In total, the HK 930 has 53 NPN transistors, 3 IC’s, 1 FET, 22 diodes and 8 power rectifier elements. There is a hole on the bottom panel for adjusting FM muting as well.
The Harman Kardon 930 receiver is a great receiver. Its unique dual power supply design gives it a place in audio engineering history as well as a great sound. While you can find the later model 730 fairly easily, the 930 is harder to find. The performance ratings are all very conservative and, if you like the HK x30 series look, then you should try the model 930 out if you get the chance.
I own a 930 that I purchased in Toronto in the early 1970’s which still works fine and now will go to my oldest son shortly, mine has the wood covering
I have a 930 from new in the 70s I think I paid £ 270.00 what a very good deal. and can vouch for the comments in this article, Sure it’s old now and still giving superb service sounding very good. But what can I replace it with when it finally goes to the the great reper in the sky?
Don’t replace it, fix it. You owe it, it does not owe you. I hear this over and over and I can truthfully say over 90% of the people that get rid of them are very, very, sorry and can never find a piece to replace it, unless they are into theatre. I will buy it if it dies from you. Keep my #. If you go the tech route and fix it, wait for an excellent tech that does it in his sleep and put out the money, tech reviews, and be patient so it will be properly re-capped and last another 50 years. It will. Kevin.
Kevin, I have a hk 930 that I bought new in 1974 and have not used since I bought a hk theatre receiver and a hk discx5 player. I am relocating and looking to sell everything including two milk crates of 1970s LPs also have 6 Bose speakers.
Hi William. I would be interested in your HK930 if you’re based in the UK?
How much are you asking.
Hi. Did Kevin buy this amp from you? I am looking for one … preferably not working but in nice condition esthetically. If you still have the amp I would be interested in buying it and fixing it properly. I am an electronics tech that collects HK stuff. Thanks, Dave
I am interested in purchasing the HC receiver. How much ? Any professional service in its hx Have you shipped before? Concerned about receiver damage Thanks Dave
I’m interested in the receiver
I keep my HK 930 for those nostalgic nights. An integrated amp (preamp plus amp, no tuner) that is getting hard to source, and that has similar slew rates and 100KHz frequency range is the Onkyo A-9110. It is significantly better sounding than the 930. You won’t be disappointed.
I, too, have an HK-930 that I purchased in the 70’s. It still wows me. If you like the sound of your 930, you’ll love the sound of an Onkyo A-9110. Same full wide band 100KHz and high slew rate attack with a solid low end and a captivating and often surprising sound stage. It’s actually better than the 930 and has become my go to amp.
I purchased a 930 with wood case a couple years ago on a whim for 200$. It sat for a year or so as I’m using several other vintage rigs and just didn’t get it into the rotation. Well I finally got it out and ready. I polished the wood case and hooked it up. I’m sure glad I did. It has replaced my beloved Marantz 2335B. I have it hooked to Klipsch Fortes and the sound, to me, is sublime. Powerful and clean. Tight yet robust. I will never part with it.
Take note of my comment Craig. I’m not sure I directed it to you. Kevin.
Will do! I absolutely love this stereo!
My first purchase in 1977 was a 2235B. I loved that thing. I lost it in the Divorce somehow.. In Sept of 2023, I purchased for $325 Canadian a Marantz SR 4000 and I am very happy with it. I recently purchased a Harmon Kardon HK 670 for $325 Canadian and I am still using the Marantz SR 4000. I also in Oct 2023 bought a Harmon Kardon HK 930 and I paid $200 but I knew it needed some love so its in the shop. I was really thinking about buying another 2235B probably because I know there is one for $ 600 Canadian in a garage. less than a mile from my house as the fella sells records and buys estate sales. But reading your comment may have just saved me some $$$$. I thought the HK670 and the HK 930 were better value. I can’t wait to get the HK930 back from the shop. It was working when I brought it home but was making noises it should not make !!!! Now you really have me thinking do I really need a Marantz 2235B ???? Thank You for your comment maybe you just saved me !!!!
I keep my HK 930 for those nostalgic nights. An integrated amp (preamp plus amp, no tuner) that is getting hard to source, and that has similar slew rates and 100KHz frequency range is the Onkyo A-9110. It is significantly better sounding than the 930. You won’t be disappointed.
Are you an Onkyo salesman?
I bought an hk 930 in 1972 in santa clara california where I lived for several years. I moved to chile in 1981 and I brought with me my excellent, faithful and old hk930. In its construction, practically only discrete elements were used, which makes it very robust and if repair is necessary, it is easy to obtain parts. I have always used it connected to four large speakers and its 45 watts per channel really is more than enough to power all the speakers. The lack of a digital tuner is not a problem since it is extremely stable in frequency. Apart from having it connected to a teac 1230 open reel, a turnable empire and a technics sh8020 equalizer, all from the 70’s, I use it as a casio sk3500 keyboard amplifier, the only modern element of this rig. The hk930 is something that, due to its quality, robustness, efficiency and fidelity, is difficult to replace.
I’ve had my wood cased HK930 for about 20 years. Bought off ebay for not very much I used it in our shared office at the local FE college. it was an absolute godsend during summer marking, loved by everyone in the office. It came home when I retired and is now in the study driving a pair of classic Spendor LS3/5A. It’s a world export model, I’m guessing originally sold through a US PX store, I recently had a conversation with an HK930 owner wanting to use his in the UK so I went in to take photo’s of the power supply. It’s switchable for 100v (Japan) 110v, 240 V It also has a prominent switch to easily switch between 75/ 50 deemphasis for FM. Superbly built as beautiful inside as out.
Bought my 930 2nd hand at a hifi shop in 1980. It had a very soft hiss in one of the channels, that could not be diagnosed by the local tech guys. I was not bothered too much, because the sound was clean and powerful. I used it for 25 years or so, then it moved to my sons student house, where it was treated badly. Parts were missing when it came back, and the balance pot was broken. Still, I could not let it go, ordered vintage spare parts from eBay, replaced the 4 large Elna caps and the Hitachi transistors. Again it shines, and drives several pairs of vintage speakers in my 2nd setup. The hiss is still there, but at my current age only audible when I listen very closely to the tweeter (and only with my best ear ;-).
Replace the transistors (8)in the receiver pre amp w ksc1845s. You probably have a leaky transistor.
https://youtu.be/Gx8Uw2QxUkc?si=uAjbc9ShjNJhym_I
I owned an H-K 430 Rec. – bought new in Jan 1977. Kept it a few years . Amp part had nice, full sound (but only 26 W/channel?) I was not – however – totally impressed with its FM section. (We had a particular hip station near Wash, DC at the time I wanted to get)
So – – I went Tandberg -bought (new in 1982) a Tandberg 2045 Rec. (one of the last ones with the nice Rosewood veneer cases) I still have it (in fact it’s next to me now – on and playing classical on FM!) Even nicer sound than the H-K (though the H-K not bad at all) FM is better with the Tandberg though. (But it was more money – and does not have the neat “twin-powered” design.)
This HK-930 owner was a die hard Marantz fan with a 2230 since 1975. In about 2019 I got the 930. Bye bye Marantz👋. Kept the Polk model 10s. Oh good heavens what a major improvent. I know there’s finer stuff on up the mountain but any signal input to this 930 just comes to life in a warm and robust way. Wonderful depth of sound, not a flat wall of sound but more like a deep forest if that makes any sense? I make my living tuning pianos and I’ve got these dang ears to try and satisfy! Twin power dude👍👍
You all got me wanting to try the ONKYO A-9110 now. Classic Receivers.com is a great place🤗