HK-730.........Common ground?

stubby

Hey all, just picked up a vintage Harmon Kardon HK-730 receiver and although it is a dual mono design, I was curious if it was possibly a common ground amp. Much like the first series of Aragon 4004, 2004 amps. I picked it up to see how it would match with my RTA 12Cs. Thought about hooking it up to the CRS' (pin/blade) to have a listen as well but don't want to blow anything up:eek:. Have read nothing but good about the quality of sound and bass extension from "just" 40 WPC.

And WOW, this thing is a heavy mother.

stubby

Conradicles

I can't answer your question, but that baby gets rave reviews. Share your thoughts in the future. I want one for the man cave rig.

thesurfer

stubby wrote: »

Hey all, just picked up a vintage Harmon Kardon HK-730 receiver and although it is a dual mono design, I was curious if it was possibly a common ground amp. Much like the first series of Aragon 4004, 2004 amps. I picked it up to see how it would match with my RTA 12Cs. Thought about hooking it up to the CRS' (pin/blade) to have a listen as well but don't want to blow anything up:eek:. Have read nothing but good about the quality of sound and bass extension from "just" 40 WPC.

And WOW, this thing is a heavy mother.

stubby

40 watts, from that H/K, is alot of clean, pure power, My brother had one,, blew away his friends 100 WPC Kenwood,

Gavin.Wright

Can't you check it with a multimeter? Just set it to low range resistance and read between the two ground posts, if it is common ground you should read very low resistance, close to zero ohms...

stubby

Gavin.Wright wrote: »

Can't you check it with a multimeter? Just set it to low range resistance and read between the two ground posts, if it is common ground you should read very low resistance, close to zero ohms...

Good idea! Broke out the trusty Craftsmen multi-meter and got a reading of .4 ohms. Is that low enough?

cnh

stubby wrote: »

Hey all, just picked up a vintage Harmon Kardon HK-730 receiver and although it is a dual mono design, I was curious if it was possibly a common ground amp. Much like the first series of Aragon 4004, 2004 amps. I picked it up to see how it would match with my RTA 12Cs. Thought about hooking it up to the CRS' (pin/blade) to have a listen as well but don't want to blow anything up:eek:. Have read nothing but good about the quality of sound and bass extension from "just" 40 WPC.

And WOW, this thing is a heavy mother.

stubby

I just picked up one of these, myself, and can't agree with your appraisal more! Not sure if it's common ground. I kind of doubt it, because those power transformers are truly separate. It's almost like a Dual Mono design. But I'm no amp design expert. Some of the guys probably know.

But you're right about the weight of the bass on this. Mine may need some tuner alignment because it's not pulling in as many FM station as it could, but otherwise it's in great shape.

Just picked up a set of Monitor 10As this evening and will fire those up tomorrow on this.

Enjoy...it's one nice vintage piece!

cnh

F1nut

Broke out the trusty Craftsmen multi-meter and got a reading of .4 ohms. Is that low enough?

0.4 ohms? Yeah, it's common ground.

stubby

F1nut wrote: »

0.4 ohms? Yeah, it's common ground.

Great! Thats what I wanted to hear. Thanks to everyone for their input. Will put it through its paces this weekend.

stubby

mhardy6647

Very, very nice receiver is the hk730. Not nearly as common as the less powerful (and less expensive) but also very nice hk430.
The none-too-common hk A402 integrated amp is - as far as I can tell - the preamp and amp of the 730, sans tuner.

Free tip: Vintage Polk Audio loudspeakers mate very well with the hk 330C/430/730 generation of receivers.

mhardy6647

Free tip: Vintage Polk Audio loudspeakers mate very well with the hk 330C/430/730 generation of receivers.

Yeah, it's a 430, not a 730... but they look almost identical (the 730 has a little pushbutton - which IIRC is a dimmer for the blackout dial lighting? - just below and to the right of the tuning knob)... and they both love the Polks! :-)

BTW, in case you didn't know, hk has many, many of its legacy models' manuals on-line at www.harmankardon.com
or, more specifically, http://www.harmankardon.com/EN-US/Support/Pages/SupportOverView.aspx

The hk730 manual may be downloaded from http://www.harmankardon.com/resources/Brands/harmankardon/Products/ProductRelatedDocuments/en-US/OwnersManual/HK730%20om.pdf

cnh

Nice ad. I'm glad we have a lot of good Tech-heads on this site, .4 ohms! Yet 'another' meter I need to pick up. Does it EVER end?

When I need quick Tech input, I usually consult a friend who has advanced Degrees from MIT (the University in Cambridge, not the cables; lol) and is a brilliant software engineer--among other things. He runs a set of Boston A200s. A very nice speaker, BTW!

I just picked up my Monitor 10s (Peerless) last night. What a nice speaker that is! So far I've hooked them up to the Marantz 2265 (and they actually sound pretty good with the Marantz--I've found the Marantz varies a lot according to the speakers).

Up next the HK 730 and Polk M-10s! That should be something. But I might not get to that till later. Daughter is home today and a trip to the Mall is obligatory! I have no classes in the afternoon on Fridays! Friday afternoons are 'good'!

cnh

stubby

mhardy - thanks for posting the cool vintage ad! Going to find out how nice a match vintage Polk/HK products are this evening. Will post my "findings" later.

stubby