4-ohm speakers with 8-ohm HK receiver

[musiclifeline]

Hey all,
I've got a pair of B&W DM610i speakers (4 ohms) and a Harman Kardon HK3480 receiver (8 ohms)... Each speaker has separate pairs of inputs for high and low frequencies, and I'm wondering whether it would fry anything if I connected my receiver's A channels to the low frequency speaker inputs and the B channels to the high frequency inputs.

Would this be presenting too much impedance? I've got plenty of ventilation around the receiver...
Thanks,
m

 

[mulester7]

Hey all,
I've got a pair of B&W DM610i speakers (4 ohms) and a Harman Kardon HK3480 receiver (8 ohms)... Each speaker has separate pairs of inputs for high and low frequencies, and I'm wondering whether it would fry anything if I connected my receiver's front channels to the low frequency speaker inputs and the surrounds to the high frequency inputs.

Would this be presenting too much impedance? I've got plenty of ventilation around the receiver...
Thanks,
m

.....MusicLifeLine, I don't see a problem with impedences, but there could be a balance problem....some here say most-times, they don't get the same amount of volume from mids/surrounds as they get from the fronts in various modes....but dispair not, someone will be along soon that knows surround receivers far better than me....which would be EVERYONE, haha.....

.....and welcome.....

edit:....I just noticed after reading again you are talking A and B outputs from the receiver....I assume you mean main/front outputs from both A and B, so that should have balance....we still need to wait though, for someone with experience to show up.....

 

[musiclifeline]

(I read in my original post that I wrote "front" and "surround"... hadn't had coffee yet. The HK3480 is a stereo receiver... duh. I meant the "A" and "B" mains.)
-m

 

[mulester7]

(I read in my original post that I wrote "front" and "surround"... hadn't had coffee yet. The HK3480 is a stereo receiver... duh. I meant the "A" and "B" mains.)
-m

.....and yes, I can vouch for coffee is an eye-opener....and much needed at my house early....ok, you have a stereo receiver with two amp sections....I'd say try whatever with the 4 ohm speakers, and monitor the amp sections for heat....if your receiver is any quality at all, it should arrive at "thermal cutout" before any damage is done....somewhere along the path, notions of a seperate slave amp might come into play if you have the ablility to take the two sides of the pre-amped signal/source to the slave amp through pre-outs on the back....but if you're looking at laying out money for a slave amp to add to a 2 channel receiver, you might consider going to a quality surround receiver and achieving surround with more speakers....this is probably not much help, but I would need to be there.....

 

[agarwalro]

HK says its ok

As per speck for your receiver on the HK website http://www.harmankardon.com/specifications.aspx?Region=USA&Country=US&Language=ENG&cat=REC&ser=&prod=HK 3480&sType=C

you should not have a problem connecting 4 ohm speakers to the receiver.

Welcome, you have just joined the most informed and unbiased community of audio/video enthusiasts. With time you will realise that people here are really helpful and wont mind dissing your mistakes

 

[musiclifeline]

My setup is pretty much just for music, so I'm not really into the surround idea (thus I went for the HK3480). The receiver doesn't get too hot, but I don't exactly crank it, either. I've heard people say that -27 is a "normal" listening level for this receiver (with matched speakers), and I'm getting "normal" at around -23 to -27, depending on the recording. DVDs seem to require a bit more (-20 to -23)... With straight audio, it sounds like some of the mids and maybe upper bass are missing, but it could be because of the speakers, not the receiver.

 

[MDS]

The A+B speaker terminals on most receivers are wired in parallel which would cut the impedance in half.

The 4 ohm rating of the speakers was calculated using both drivers but now you will be driving each separately. If the average impedance of one of them is substantially higher than the nominal 4 ohms stated for the whole speaker, then you MAY NOT have a problem. But what will you gain by using a+b to hook up the speaker? Doesn't sound like a good idea to me.

 

[mulester7]

The A+B speaker terminals on most receivers are wired in parallel which would cut the impedance in half. But what will you gain by using a+b to hook up the speaker?

.....MDS, last half question answered by first half statement....it sure could bring more authority from a lesser amount of ohmage SEEN by the amp sections as they stood up on back legs to fire 2-3 ohm watts as per bi-amping....another quirk in the mix could be the damping factor is halfed against cleanness....could go to thermal cutout also, but he said he didn't listen at thunderous levels....I'd still say try whatever, but monitor the amp sections for possible heat increases.....

 

[mulester7]

With straight audio, it sounds like some of the mids and maybe upper bass are missing, but it could be because of the speakers, not the receiver.

....you guys are going to cringe on this one, and do what ya' gotta', but here is a prime opportunity to do an AB with cross-wiring the speakers at the "normal-full-range" posts of the speakers....I for sure would if I heard what MusicLifeLine has described....may need to cut the highs at about 10-12K for possible raspy, maybe not.....

 

[mulester7]

.....Guys, listen, I'm keepin' up with it, and current reports indicate mule ain't nuts....my four speakers wired in one-circuit-deep series gave point/imaging to harmony vocals that simply is not there since back to normal....

.....but with time, I wanted to AB and came back....I ended up wanting a little more warmness to it, I guess....my cross-wiring ended up being heard as thin when compared, and that's the ONLY reason I went back to normal one-deep parallel, whose wiring configuration resembles a box, and completes a circuit....put another box on top of that one, and suddenly the word parallel comes into play??....I say it was there to start with on the first box....parallel one-deep....and let's keep it simple, and say a cross-wired configuration to one speaker, IS, series, one-deep, on the OTHER SIDE of ohmage-movement....

.....I can't emphasize this enough, some of you with mud need to try cross-wiring....I'll buy any stuff that melts....if you don't try your mains, ahem, everyone, however pushed, you have no authority to say your mains are wired correctly, dost thou?....then again, maybe my speakers are different from EVERYBODY ELSE'S as to mechanicals.....don't think so....they are but an exercise in crossover rolloff and tunnels of styrofoam damping....made by a friggin' Genius, imo....I've caught him winging it a few times on stuff, but he made these speakers, buddy, I'm done.....

.....hey, if you think you might have mud up to the mids, and/or, weak sounding mids, and especially, if you have a 2-ch stereo receiver/slave amp pushing them, you know.....I quit on the subject....but....well....you gotta' watch me....I lie a lot, haha....

.....good site....lotsa' guys on tight budgets....and Dad's, I'll find you, and whup you myself, if I find out you didn't satisfy bicycle needs first....

.....listening to Charlotte Church....when she was about 16....her performance live by DVD from the concert in Cardiff, Wales, was the best over the CD, which had many of the same songs, but was performed in a studio situation, with the orchestra, concert and studio within a few days of each other probably, whew, and although I feel the DVD overall is best, about 4 on the CD are better than the SAME four on the DVD, ya' know?, soooo, ya' just gotta' have BOTH, haha....

.....Charlotte Church--"ENHANCEMENT", that's the name of both the cd and the dvd with both having the same close-up faceshot of a young queen....ATTENTION...WAF Factor!!....I quit....down with mud......

 

[musiclifeline]

I've tried just connecting to the HF drivers and just to the LF drivers -- surprisingly little difference, though I assume if you're just wired into the HF driver, the LF driver will act as a passive resonater...

In any case, I've also come to the conclusion that the loss of some mids is mostly due to a lack of a separate driver for them, as in the larger speaker modes. My solution for right now is to roll off the highs and lows a bit to make the mids a bit more prominent, but I can't seem to get a balance that works for all recordings -- everything seems to require at least some tweaking. And since the tone controls are only on the unit itself and not the remote, it's getting kind of annoying... (laziness flames on!)

Anyway, thanks for reassuring me I won't melt anything and that I'm not simply putting more power than I need to into these speakers.
-m

 

[mulester7]

everything seems to require at least some tweaking.

.....MusicLifeLine, with decent equipment, I have found it necessary to re-tweak with any change of source for a long time now....you know what you're doing....happy listening......

 

[musiclifeline]

Thanks mulester. I tell ya though... for the amount of money these setups cost (and mine's super cheap in comparison to many), not only should you not have do any tweaking, but the things should brew coffee and take messages too.

 

[mulester7]

Thanks mulester. I tell ya though... for the amount of money these setups cost (and mine's super cheap in comparison to many), not only should you not have do any tweaking, but the things should brew coffee and take messages too.

.....MusicLifeLine, I am just thankful I have decent enough equipment I CAN do a good deal of tweeking....I'm sure you'd agree....if you're going to stay 2 channel stereo, consider seperates for sure....with your present situation, wire the HF speaker terminals of both speakers, with correctly wired configuration to the receiver output posts mains A, both left and right sides....then wire the LF speaker terminals correctly configured to the output posts at the receiver mains B....when you choose A and B for speakers, you should hear something very good....powerful voltage into wattage kick from paralleling speakers through raising the resistance.......

 

[Buckeyefan 1]

Hey all,
I've got a pair of B&W DM610i speakers (4 ohms) and a Harman Kardon HK3480 receiver (8 ohms)... Each speaker has separate pairs of inputs for high and low frequencies, and I'm wondering whether it would fry anything if I connected my receiver's A channels to the low frequency speaker inputs and the B channels to the high frequency inputs.

Would this be presenting too much impedance? I've got plenty of ventilation around the receiver...
Thanks,
m

I think this thread got a little off track. IMHO, don't do it. Never run A+B, especially if you're running the system at high levels. The amp will shut down. Heat kills electronics, and overdriving an amp will create loads of heat. HK's are known to run hot, just like Denon.

 

[PENG]

As per speck for your receiver on the HK website http://www.harmankardon.com/specifications.aspx?Region=USA&Country=US&Language=ENG&cat=REC&ser=&prod=HK 3480&sType=C

you should not have a problem connecting 4 ohm speakers to the receiver.

All of the 7 channel HK receivers have very high idling and maximum power consumptions. Example, 890W for the AVR235. The 3480 has only 2 channels, and its maximum consumption is only 280W.

Interestingly, it's output is rated for 120WX2 into 8 ohms and 140WX2 into 4 ohms. Input=Output? No way!

I agree with Buck, it is not a good idea to "bi-amp" your B&W's with the A+B thing. Aside from impedance issue, you are not really bi-amping, as someone pointed out, the A,B terminals are likely connected in parallel internally. The 3480 has two amplifiers, not 4. You may be bi-wiring but definitely not bi-amping. There is no gain, only risk.

 

[mulester7]

All of the 7 channel HK receivers have very high idling and maximum power consumptions. Example, 890W for the AVR235. The 3480 has only 2 channels, and its maximum consumption is only 280W.

Interestingly, it's output is rated for 120WX2 into 8 ohms and 140WX2 into 4 ohms. Input=Output? No way!

I agree with Buck, it is not a good idea to "bi-amp" your B&W's with the A+B thing. Aside from impedance issue, you are not really bi-amping, as someone pointed out, the A,B terminals are likely connected in parallel internally. The 3480 has two amplifiers, not 4. You may be bi-wiring but definitely not bi-amping. There is no gain, only risk.

....Peng, educate me here....how is he not bi-amping which is accomplished at the speaker with seperate terminals?....nobody said anything about strapping amp sections....

 

[mulester7]

I think this thread got a little off track. IMHO, don't do it. Never run A+B, especially if you're running the system at high levels. The amp will shut down. Heat kills electronics, and overdriving an amp will create loads of heat. HK's are known to run hot, just like Denon.

.....you'd try it and so would I, grin.....never use A+B?....why the option?....sure, the amp sections would get red at high levels....but if your speakers only sound good LOUD, you need to go shop for speakers.....

 

[PENG]

....Peng, educate me here....how is he not bi-amping which is accomplished at the speaker with seperate terminals?....nobody said anything about strapping amp sections....

mulester7,

Sorry if I was not clear, the 3480 is a two channel stereo receiver, it has only one amplifier for each channel. Bi-amp usually means for each channel, the low and high frequency sections of a speaker are separately powered by an amplifier. So for 2 channel Stereo, you need 4 amplifiers to bi-amp. The 3480 provides two sets of L/R speaker terminals but the two sets of terminals for each channel are still powered by only one amplifier.

The extra set of speaker terminals are useful if you want to have the ability to switch quickly between two different pairs of speakers for whatever reasons (e.g. A,B compared two different pairs of speakers, different speakers for different type of music, or simply to have more speakers to "fill" the room, etc.). When you connect two pairs of speakers and select the A+B, you do have to be careful because the amp will effectively see half of the impedance of each speaker because the two sets of terminals are, in most cases, internally connected in parallel. Hope this helps.

 

[mulester7]

mulester7,

Sorry if I was not clear, the 3480 is a two channel stereo receiver, it has only one amplifier for each channel. Bi-amp usually means for each channel, the low and high frequency sections of a speaker are separately powered by an amplifier. So for 2 channel Stereo, you need 4 amplifiers to bi-amp. The 3480 provides two sets of L/R speaker terminals but the two sets of terminals for each channel are still powered by only one amplifier.

The extra set of speaker terminals are useful if you want to have the ability to switch qickly between two different pairs of speakers for whatever reasons (e.g. A,B compared two different pairs of speakers, different speakers for different type of music, or simply to have more speakers to "fill" the room, etc.). When you connect two pairs of speakers and select the A+B, you do have to be careful because the amp will effectively see half of the impedance of each speaker because the two sets of terminals are, in most cases, internally connected in parallel. Hope this helps.

.....Peng, I worked with some HUGE bi-amped Peavey speakers for years while in Gospel quartets....some large bi-amped Altec's also....there used to be tri-amped enclosures, although I never worked with any....we worked with mono and mixing....bi-amping gave the freedoms of seperate tone controls and balance between the top and bottom....thanks for the reply.....