HK AVR 1550 with AR3s?

[Guest Dodger]

Hi everybody.

Since now i have driven some old AR3s with a Harman/Kardon HK670 stereo amp. Since i do live in an appartment i cannot listen at very high levels so i never had problems with the power delivered (2*75 Watts into 8 ohm) by the HK.

I am just now upgrading to a home theatre and since im low on budget i have the

HK 1550 or HK 2550 amp in mind. those provide around 50 watts per channel into 8 ohm.

my question is if the above stated recievers are capable of delivering enough power to the AR3s (just two for left and right channel, the rest are 8ohm speakers and the sub is an active one)?

do you suggest to buy another amp with more power (denon has some with reasonable power for the price...) or should i even look for an amp with pre-outs so i can amplify the left/right channel separatley with my HK670?

greetings.

dodger

[tysontom]

>

>my question is if the above stated recievers are capable of

>delivering enough power to the AR3s (just two for left and

>right channel, the rest are 8ohm speakers and the sub is an

>active one)?

>

A bigger question might be to ask if those receivers are capable of working into a low-impedance load, such as the AR-3. The impedance drops significantly below 4 ohms on the AR-3 at certain frequencies, and this might cause some receivers/amps to overheat or even shut down in some cases. The AR-3 is also low in efficiency, and therefore does require a healthy amount of power into low impedances, but if an amplifier is capable of a clean 25-50 watts-per-channel, and can deliver this into 4 ohms or below, you should not have any trouble with the AR-3 at moderate levels. 1 watt will produce 86 dB, on axis, at one meter for the AR-3.

--Tom Tyson

[Guest Dodger]

thx for you reply, tom.

i will only need moderate levels on the AR3s and i could also cut down on the low frequencies (i guess this will be the frequencies where the impedance drops very low...) since i will use a subwoofer for the very low frequencies.

the specs of the AVR 1550 say that it delivers 50 watts/8ohm (so it will be something around 80w/4ohm) and uses massive heatsinks. the (too) much-advertised high-current-capability should be helpful in the case of very low impedance.

i guess the only thing i can do is try the whole thing out.

greetings

dodger

[ninohernes]

You should not need a sub woofer with the AR-3's. They have enough bass response to provide everyone in your apartment building with bass! I think a sub woofer would be overkill with the AR-3's!! Especially since the AR-3 woofer has better bass response than most sub woofers today!

[Guest LOVEAR]

My home theatre set-up has a recent HK 70 watt x7 surround receiver used to drive the center channel, A single AR92, and the surround speakers. I use the preamp outputs on the receiver connected to a 100 watt HK integrated amp with a preamp/main in switch, so I can use it like a power amp and bypass the preamp. It is from around 1989, very heavy and seemingly well built. It drives AR9's which are the mains. For music only, the HK amp drives the 9's well in my opinion.

I like my set-up, your Amp probably will drive the 3's better than a surround receiver so try and fit it in.

[Guest rickcee]

Hi as mentioned by T>T> low imped. capacity is the key, 50 watt chan should be fine in smallish room /moderate vol. - the original AR amps/ recievers had about 55 w/ch . . . enjoy Rick

[Guest Dodger]

hey, if the original amps had only 55w/ch (into 4ohm i guess) the 50w/ch of the HK into 8ohm will surely provide enough power (and maybe run hot, but thats what i have to find out. )

thanks for the help!

[Guest Dodger]

@lovear:

right, this was my idea first. use the pre-outs and the old stereo-amp as separate amp for the front channel. sadly the HK receivers in my budget have no pre-outs. must be a cost factor.

this is apparently not without irony, since all expensive receivers have the pre-outs, but they have normally higher output-power, too. and with high power, i would not need the pre-out.

[Guest dogmeninreno]

>You should not need a sub woofer with the AR-3's. They have

>enough bass response to provide everyone in your apartment

>building with bass! I think a sub woofer would be overkill

>with the AR-3's!! Especially since the AR-3 woofer has better

>bass response than most sub woofers today!

I agree...The subwoofers are not needed with the AR3's as long as good clean watts are provided. They actually can mess up the whole system in my experience, Dale

[Steve F]

A few things to remember about subwoofers, impedances, and old AR speakers:

1. If you use a powered subwoofer, the receiver will low-pass the bass below 80Hz to the sub, and the 3's will only see 80Hz and above. Many modern HT receivers have a selectable LP crossover, but 80Hz would still be about right for the 3's. In any event, the point is that the current demands on the receiver's amp are lessened considerably when it's only driving the frequencies from 80Hz on up. HK's are generally pretty good, so I think you'll be ok.

2. Use a sub. When you select "No sub--Large" from your receiver's set-up menu, the LFE portion of the signal is folded back into the rest of the signal at 10dB LOWER level than if it's a discrete LFE out signal. This is according to Dolby's own requirements for Dolby Digital bass management. The result is that you'll get less special effects bass level using your L and R speakers full range (selecting "Sub--No, Speakers--Large") than if you used a separate sub. Maybe that's ok with you because you won't be overdriving your 40-year-old 3's, but you'll have a less satisfying Home Theater sound system.

Also, this is important: When you use a sub, it can be placed for optimum bass response, whereas the bass of full-range bookshelf speakers like the 3's is always somewhat compromised by their placement, especially if they're on stands and not in a true 2 Pi environment. AR knew this, and that's why they did the 9.

No, the bass from a corner-mounted sub won't be "boomy." It'll only be boomy if it's a lousy sub to begin with--and there are a lot of those. The "boom" occurs at frequencies much higher than a low-passed sub will handle, usually around 120-200Hz. The sub will handle from 80Hz on down. Noted reviewer Tom Nosaine has done extensive room measurements of sub responses in various locations, and corner placement in an acoustically-good room (three non-related HWD dimensions) is ALWAYS the smoothest. Look in Sound & Vision around 1999 or so for his articles. I have professionally set up, tested and demo'ed countless HT systems, and I can attest to his findings.

3. Don't use your priceless 40 year-old 3's for Home Theater bass. Don't torture them. What's the point? They were not designed for 20Hz Exploding Death Stars at levels greater than the midrange dialogue. Their adhesives have aged and dried, they're not as compliant as they used to be, the tinsel leads are more brittle--why risk it? I wouldn't.

I'd use your 3's like I use my 3a's: In a two channel music system where I can control their playback level and enjoy them for the valuable gems they are.

Buy yourself some decent modern speakers (and there ARE decent modern speakers) for the heavy lifting of home theater.

Steve F.

[Guest Dodger]

steve,

thanks for the valuable information. i surely will be testing my HT with and without subwoofer (with the crossover of the sub around 80 hz) and with the AR3s in large as well as in small position.

it seems to me that your argument about not torturing my ar3s with expolding death stars (and they will explode - starwars is coming on dvd soon...) is a valuable one.

i am still a student (but not for too long anymore...) and quite on a tight budget so i cannot afford "decent" speakers especially for my HT right now. but when the time comes i will surely stop (miss-)using my old AR3s for HT.

greetings

D

[Rlowe]

I found a set of articles (via a link in the Forum)by Floyd E. Toole, Ph.D. Harman Kardon. He prepared several articles on speaker placecment. It may be of interest. I tried the placements using my 2 AR90s and I thought it worked well ( 2 subwoofers ).

You can get the following "White Papers" at;

http://www.harman.com/wp/index.jsp?articleId=default

Loudspeakers&RoomsPt3.pdf

Loudspeakers and Rooms - Working Together

Loudspeakers&RoomsPt2

Room Mode Calculator.xls

Subwoofers (Presentation)

[Guest Dodger]

thanks for the links. unfortunatley the server always seems to be down ( i remember that a few months ago i coult't get access to the server either).

could you email me those papers or mirror them somehow?

that would be great!

email would be

dodger*at*nei.ch

greetings

raffi

[Rlowe]

I found the same problem.

Try this,

http://www.harman.com/

Go to the middle of the page.

Then look for "white Paper" icon under the moving advertisement.

[Guest Dodger]

jup, thanks for the tip. got them.