2 ch amp curiousity

snake1

Well, Geoff4rcf and I have been having a conversation and figure someone on here would know. What is the possibility of hooking up 4 speakers to a 2 channel amp? Basically bi-wiring in reverse. Split the wires coming out of the amp to power 4 speakers instead of 2. Thoughts???

billbillw

That's old school. It was sorta popular in the 60s/70s. But back then, most affordable speakers really couldn't handle much power. So people set up matching pairs in a stacked array. They could get 3db louder with the stack than with a single pair. Some of the folks over at AK still do this with arrays of Large Advents or other similar speakers. It can work OK if both sets of speakers are 8 ohms nominal, but I would not try it with 4-ohm speakers.

Overall, it ruins the imaging. Stick with one pair, you'll be happier.

snake1

What about a multichannel amp running normal wiring but the AVR setup with Audyssey DSX configured for wides and using towers?? Would it work with 2 towers for L and 2 for right running stereo?? Would the Audyssey config 'fix' imaging for 4 speaker front stereo sound??

ps hope this explanation makes sense haha!

polkfarmboy

4 speaker and front stereo sound wrong to me but ADSY should tune the two pair as one and provide some kind of 'fix'

snake1

polkfarmboy wrote: »

4 speaker and front stereo sound wrong to me but ADSY should tune the two pair as one and provide some kind of 'fix'

that is kinda what I'm thinking

polkfarmboy

Hope your not planning on running two set or mixing with those rti12's

mhardy6647

Mark Levinson rather famously stacked Quad ESL-57s; there are numerous folks who'll assert that these Mark Levinson "HQD" loudspeaker systems were the finest reproducers. Ever.

http://soundartiwakura.jp/bbs/data/cheditor/0707/soundartiwakurahqd72.jpg

4xoddic

Those are some big looms. Now I understand use of the terms weft, woof, & filler by audiophiles.

snake1

Thinking about running another set of 12s as wides for surround but also wondering about 4 of them in stereo using audyssey dsx.

4xoddic

Comb Filtering, Acoustical Interference, & Power Response in Loudspeakers

http://www.audioholics.com/loudspeaker-design/comb-filtering

My inadequate understanding of audyssey dsx & Pioneer MCACC would lead me to believe each speaker is adjusted individually; and the programs have little, or NO, capability to adjust for the effects of comb filtering when all speakers are emanating waves. It's the interaction of these waves as they pass your ears that leads to some frequencies canceling & others adding up to greater dBs.

I used to enjoy teaching waves in Gen. Science. Take a really long rope & put a knot in every meter. Force the students outside & line up on the sidewalk to get an understanding of the wavelengths of their fav FM stations. Unfortunately, USDs frown on buying all the science toys useful to study wavelengths, refraction, diffraction, comb filtering. Anybody else have a pair of diffraction grating sunglasses?

http://www.rainbowsymphonystore.com/diffraction-grating.html

Face

I like Audyssey for setting distances and levels, but it's best to fine tune yourself...especially in the bass region. A tool such as the Omnimic with the multi-channel DVD are perfect for this.

aboroth00

Running speakers in parallel from a 2ch amp will half the resistance and require double the current. As bill mentioned on top you can get away with using 8ohm speakers, but if you use 4ohm nominal speakers, the amp will effectively see a 2 ohm nominal load. But as others mentioned, comb filtering will be a major concern.

aboroth00

nbrowser wrote: »

I said it in the other thread, I'll say it here, I see bad things happening...just sayin.

curiosity killed the cat?

snake1

nbrowser wrote: »

I said it in the other thread, I'll say it here, I see bad things happening...just sayin.

It may for stereo music but I still like the idea of having wide towers for 7.1 surround. Geoff and I have talked at length about it plus he's had experience with that kind of setup. This was more of a side curiosity for music.

snake1

aboroth00 wrote: »

Running speakers in parallel from a 2ch amp will half the resistance and require double the current. As bill mentioned on top you can get away with using 8ohm speakers, but if you use 4ohm nominal speakers, the amp will effectively see a 2 ohm nominal load. But as others mentioned, comb filtering will be a major concern.

So with the 12s everything would work as long as I switch the Amp to 4 ohm mode?

Geoff4rfc

snake1 wrote: »

So with the 12s everything would work as long as I switch the Amp to 4 ohm mode?

On my amps, there is no switch, it just recognizes the impedance.

snake1

Geoff4rfc wrote: »

On my amps, there is no switch, it just recognizes the impedance.

Mine has a 4-8 ohm switch and a 2-3 side so it could handle it in theory.

Face

Just because a speaker is rated at 8ohms, doesn't mean it's impedance curve doesn't dip down to 4 or 3 ohms for a brief period. To run two of these in parallel could be detrimental to your amp, not to mention being a cacophony of sound. On the other hand, to wire them in series, the first speaker's voice coil inductances and crossover parts will effect the second speaker's frequency response, I would pass on that too. If you want a "front wide" setup, pick up a processor with that capability and a second two channel amp.