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4 Ohm Load

I've got a Pioneer SX-636 receiver at my office that I listen to every day. I've been curious how it would sound if I brought it home for a night to hook up to my Vienna Acoustic Beethoven Concert Grands. The VA's are 4 ohm and my only concern is that the receiver may not enjoy trying to push that load. Anyone have an idea if this is no big deal or smoke waiting to happen? There's a good reason why I'm curious to try this but I won't bore you with that.
Thanks,
Mike
ndfan
magfan
1,583 posts
 
It is NOT the sensitivity that matters most.

The 'goodness' of a load is about phase angle.....How much does current lead or lag voltage? The moderate phase angle of this speaker is not a 'bad' load, though the impedance dip at 90hz to 2.83 ohms IS a redflag.

http://stereophile.com/images/archivesart/506VABFIG1.jpg

I had the SX-727 a LONG time ago and it was a warm one. Be careful and you should be OK.
almarg's avatar
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almarg
9,670 posts
 
Hi Magfan,

Your point about the importance of phase angle is certainly a good one. However, the specific issue I was addressing, the possibility that amplifier clipping caused by the relatively low sensitivity of the speaker coupled with the low power rating of the amp might in turn cause tweeter damage, I think would still be a concern even if the speaker were purely resistive, with 0 phase angle at all frequencies.

Best regards,
-- Al
ndfan OP
8 posts
 
Guys,
Some great response here. I keep learning. I'll keep it backed off. I've got an integrated amp that's adequte power for the VA's but I really like the tone of the old SX series receivers and my integrated has no tone controls. You get what you get.
I used to have the SX-1250 with JBL L300's and liked the ability to adjust the tone, especially at low litening levels. I suppose I could buy up into the SX-850 or higher and use just the pre amp section? Maybe there's a pre that's more modern that will do what I'm looking for and not cost thousands? I had said that I wouln't bore you with why I wanted to hear this old receiver at home in the first place, but that's why.
Thank you again for your feedback and the ohmformation.

Mike
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almarg
9,670 posts
 
Mike,

You're welcome. Keep in mind that boosting the bass, via tone controls or an equalizer, will dramatically increase the power demands on the amplifier, also increasing the likelihood that an underpowered amplifier will clip. Although if the boost is modest, and the volume levels are low, you'll probably be ok.

Best regards,
-- Al
rrog
1,958 posts
 
I used to own a pair of JBL L300s and I'm still kicking myself for selling them. Now that speaker would work fine with your SX-636.
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