Jump to content

3 Channel Stereo


Mr._Music_Fan

Recommended Posts

Hey guys,

 

I am thinking of buying a Klipsch Academy speaker to complement my Forte II's.  I am using a Marantz 2252 receiver to drive my Forte's and I listen to vinyl and a couple of tv shows. 

 

Goal: Create a center channel to enhance the stereo sound.

h

Questions:

 

A. Is it possible to use my "B" set of speaker terminals, specifically using both positive outputs from the Right and Left terminals to power the Academy speaker?

 

B. is this really even worth it? Am I wasting my time/money on chasing a golden goose?

 

C. Is the Academy speaker really that good of a center channel?

 

Thanks in advance!

 

 

Link to comment
Share on other sites

With the Forte's, stick to just two speakers.  All of the sound will come from the front stage with 3 speakers and imaging and depth will centralize.  This is not necessarily bad but, most 2 ch people will favor the better imaging of 2 ch.  No, to using the speaker terminals of the Forte's to drive the Academy.

Link to comment
Share on other sites

Its no golden goose, that is for sure. What it is is just different. Not better, not worse... just different.

Most of us prefer better imaging of the individual layers by using two speakers, and what three or more speakers do is to create a wall of sound.

Link to comment
Share on other sites

Properly implemented 3-channel sound can work well (especially if the R and L mains are wide apart creating a hole in the sound stage), but it requires a derived center channel signal amplified about 6 dB down from the mains.  Some older receivers and preamps have a derived center out channel terminal, but that will require a separate loudness controlled amp to power the center speaker.  

 

The derived channel can be created from R and L preamp out terminals (easy box to build - see the Dope from Hope article on the subject), but again that requires a separate amp.  A similar circuit can be built but using the R and L speaker out terminals to power the center speaker without a separate amp, and an L-Pad attenuator can be incorporated to adjust the loudness of the center speaker.  A properly done 3-channel set up can fill out the sound stage and improve imaging in my experience.  However, simply using the B-channel speaker terminals on the receiver or amp is not the correct way to create 3-channel stereo.

Link to comment
Share on other sites

My general experience in running speakers off the A and B channels is I don't like it.

 

Running the B channel cuts the dynamic headroom substantially to the point that it becomes punchless and flat.  I much prefer the livelier sound running just off the A channel alone in 2.0 mode.  This was with an older 60 wpc Technics receiver.

 

If you want to run 3.0 (which I like a lot especially for TV) I would suggest a modern AVR which can use room correction technology like Audyssey to properly balance the L/C/R.

 

That's not exactly what you are trying to do with your B channel/center speaker setup, so your experience might work better than mine, different speakers, different receiver, etc.

Link to comment
Share on other sites

OP - is this just for a 2 channel set up(as opposed to Home Theater)? Do you have a "hole in the middle"of your stereo image?

PWK was a great proponent of the third channel if there is a hole in the middle because of Left and Right speaker placement and room size. There are articles about it in the 'Dope from Hope' archives. If I can find I will return with a link.

Oops sorry I missed Seadog's post.

Edited by babadono
Link to comment
Share on other sites

As others have mentioned you can do the phantom center channel, 3 speaker stereo setup... The PDF link from "Babadono" is the place to start. Or you can Google it and find lots of reading material.

In regards to your questions...

A: I don't think your Marantz would appreciate having the Left/Right positive terminals connected to the same speaker.

B: Only you can decide if you like the way it sounds in your room with your equipment. Try it, experiment with it and find out.

C: The Academy is a very good center channel speaker. However, it's not the closest match to Forte II's. The Academy has an exponential horn and is a match to the original Forte, which has exponential horns.

The Forte II's have the Tractrix midrange and the KLF-C7 is the closer match since it has the updated Tractrix horn.

Edited by GPBusa
Link to comment
Share on other sites

If you do it at all, use the second version of PWK's circuit for a derived 3rd channel, with a third power amp channel.  The link babadono sent you is the correct one.     Klipsch had issued an earlier circuit that did not use a separate mono power amp (or one channel of a stereo amp); IT TURNED OUT THAT SOME LATER AMPS WOULD NOT TOLERATE THIS CIRCUIT. 

 

I use a derived third channel -- three channels across the front -- to play 2 channel music, but I use the "multi-channel stereo" function on my preamp-processor; it creates a mixed channel in the center that is attenuated a bit.  Sometimes 2 channel music sounds better that way, sometimes not.  I read somewhere that it depends on the mic placement in the original 2 channel recording.  I don't know if that's true. 

Link to comment
Share on other sites

I have an Academy between my Forte IIs for HT. Would never use it for 2ch though. Mostly because it's not needed, my Fortes are not that far apart. They image so well too that it sounds as if the center is on anyway.

Plus as said, the Academy is not a perfect match to the Forte IIs. If you had to do a center because of space, I'd use another Forte II.

So is the KLF-C7 really a better match to the Forte II for a center in HT? Should I be looking to switch out?

Link to comment
Share on other sites

So is the KLF-C7 really a better match to the Forte II for a center in HT? Should I be looking to switch out?

I think it is... The Tractrix midrange really made a difference. I used one between a pair of Forte II's, then between Chorus II's. The only thing better is when I was able to put together a 6.1 setup with two pair of Chorus II's (front left/right and left/right surround) with a pair of Forte II's as center front and center back.

Link to comment
Share on other sites

I believe a number of the older tube amps and receivers made by Fisher and Scott were made to run a center channel.

 

I've never seen/heard of anyone who ran three speakers from one of these amps but always wondered what it would sound like.

I have and they sound just fine, depending upon the size of the room. If a big room then they are an addition to the sound, but in  a smaller room they will mess with the soundstage, depth of presentation etc.

Link to comment
Share on other sites

The question is can you take a R and L channel of the amp and run 1 speaker from it?

 

I've never tried it but if it can be done why not try it.   It will drop the ohms from 8 to 4 and put a little more strain on the amp. 

 

It might sound fine for TV shows, never know unless you try it.  For just TV not stereo records it might sound fine.  

Link to comment
Share on other sites

Thank you all for your feedback.  I currently use my setup for records, but I am considering expanding my setup to a 5.1 setup. The setup include a pair of KG4's for rears and an Academy or KLF-C7 or RC-3.

 

Eventually this would also require a different receiver too, as my Marantz 2252 doesn't have 5.1,

Link to comment
Share on other sites

  • 2 years later...

Anyone ever try this? (See attached photo)

 

It’s from the Klipsch biography. 

 

Im still working on getting my two channel mx110/MC30/Cornwall system up and running. But I always wondered about the Klipsch three channel stereo.  I know the mx110 preamp has a R, L, and a R+L output. That would require a third MC30. 

If you look at the photo though, Klipsch is running all three off of just two power amps. 

AAF688C4-8B78-46BD-9B2E-589304C1D160.jpeg

Link to comment
Share on other sites

7 minutes ago, davestef said:

Anyone ever try this? (See attached photo)

 

The trouble with that is the center channel is "A-B", so the "A" channel content in the center is in-phase with channel A, while the "B" channel content in the center is out-of-phase with Channel B.

See the article referenced in my sig for some line-level solutions to this problem.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...