Hafler's passive pseudo-quadraphonic speaker hookup using a stereo amp
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zenith2134
Lunatic Member
I remember when Paul posted that diagram. I tried it on 2 seperate amps, and was really impressed by the whole theory of it. Didn't sound bad, either. In fact this was a very interesting effect, at least on my system. After a few days I grew tired of it and removed the surround speakers. Now I wanna hook it back up, with some gear I didn't have at that time and see how it sounds.
Outshined, can you give me some more detail as to how you have set up the Carver? I have read up a bit on it and it seems it is put between the preamp and power amp.Is this correct? Are you using any rear speakers. Some more detail on your setup would be appreciated.
Thanks.
Nash Bap
Thanks.
Nash Bap
outshined
Super Member
Nash,
I use a Carver C-4000, and it has a built-in Sonic Holography circuit.
If you will use an outboard SH Generator (C-9 or C-9AV) I wouldn't put it between the preamp and power amp. It should go in a tape monitor or "external processor loop"
I don't use any rear ambience speakers at the moment, but have tried it and it really enhances the Holographic effect. It is phenominal with DVD's, btw.
Some things to consider with a properly set up system is speaker placement. Speakers that are too close to side or back walls will not yield optimal results. Just about 2 or 3 feet from any boundary will make it work right.
Also, the speakers must be the same exact distance from your listening chair. I measure using a tape ruler from the top back of the chair. Basically, you can measure from the chair back, or top. The measurement should be within a 1/4 inch for each speaker. (Not that difficult!) An equalateral triangle is best, but not absolutely necessary. Mine isn't. And the speakers should be a little closer together than you might normally place them.
Dipole or speakers that radiate in other than a front firing manner will not work as well, and may need some extra tweaking to get it optimal. Also, I would remove the grilles to stop interference of the speakers wave launch, which is the most common problem for optimal Holography.
With just a little tweaking, you will have sound that is extremely open, clear, and that has real depth. It is, I should mention, somewhat dependent on the recording. Closely mic'd recordings, for example, will benefit, but not as much as a recording made with just a few mics. Every recording will benefit from Sonic Holography.
If you try it, I would first play "The Dark Side Of The Moon" You will be astounded
Hope this helps, and please let us know if you try it and what you think. I know you will never listen to "flat" recordings ever again
:thmbsp:Thanks for the detailed response. If you did include rear speakers how would they be wired to the amplifier; parallel or Hafler circuit and how would you adjust the volume? I am supposing that the distance requirements you mentioned were for the front speakers.
There is a C-9 on sale presently on ebay #300160205035 . Is this what you are referring to?
Would appreciate your impressions. I know very little about these units and googling does not yield much. Is there any other model worth considering?I think I want to try this out.
Nash
There is a C-9 on sale presently on ebay #300160205035 . Is this what you are referring to?
Would appreciate your impressions. I know very little about these units and googling does not yield much. Is there any other model worth considering?I think I want to try this out.
Nash
outshined
Super Member
Unfortunately, the C-9 outboard processor does not come with provisions for rear ambience speakers. My C-4000 has 2, 20W amps built in for this purpose, along with the requisite speaker connections.
Yes, I was referring to only the front channels in my post.
What I can suggest when using the C-9 (yes, I did see that on eBay) is to connect a small pair of speakers to one of your preamps outputs (main outs) with another amp with gain controls to control the volume. The Holography circuit will be in effect. I don't believe the same measuring rules apply for the rear channels. You will want to have them further back than the front channels, and spread further apart, as well.
If this is not feasable for you, you can connect smaller, less efficient speakers to the "B" speaker terminals on your amp, if it has them. This will give you pretty much the same effect. Watch your impedences!
Or you can buy a C-4000, with the silver face. This has the most "radical" holographic effect. This is the only Carver that has the rear speaker outputs (well, the later ones do too)
But, really, I think you will be more than happy without the rear channels if you had to do without them. People who listen to my system (for the first time) are always looking for the extra speakers either in the ceiling, to the sides, or, even behind them! They don't believe there are only two speakers in the room. When they are convinced of this, they are surprised and want to hear all about Holography (well, maybe not the women!)
Sorry if the C-9 will disappoint as far as the rear channels go. But, as I said, I know you will love the effect with just two speaks, as long as you follow the set-up instructions to the letter. It's really not that hard at all, and worth the effort in spades.
Thanks for the quick reply. I am not that enamoured by rear speakers as much as trying to expand the sound stage. From what I have read a C-9 should help considerably with most jazz and classical which is what I listen too. And yes, I do have that Pink Floyd classic-Dark side of the Moon. I have never seen a C-9 before, so am I correct in understanding that the effect is controlled by just one pushbutton and then tuned by adjusting speaker position as outlined by you earlier? Does much go wrong with these units or are they fairly bulletproof? I am a bit reticent about bidding on the one on ebay presently since it is from an auction house and not from an individual owner. Any thoughts? Do quite a few pop up on ebay? Thanks again for your help.
Nash
Nash
outshined
Super Member
The total effect depends on mainly 2 things: speaker position (away from walls, etc... and toe-in, which is a given) You want to have the output of both speaks output "cross" just in front of your head.
The "Injection ratio" on the unit widens the soundstage a little with a recording that will benefit from it. You will most likely leave it on most of the time. There is a holography in/out button, and "normal/theoretical" These are used to tweak the effect.
Jazz recordings sound great with holography. Live classical recordings will give you a huge soundstage with the "sonic signature" of the particular venue. A sense of space that one feels when stepping into a huge space.
I cannot tell you if a particular unit on eBay or anywhere else will be a "good" one. It either works, or it doesn't. I would ask a lot of questions before I buy. I would recommend buying from someone who has used the unit and can confirm that it does, indeed work.
The one on eBay is the more desireable rack mount unit. You might ask for return priveledges if the unit does not work.
Brian
An Old Geezer
Most receivers do. It actually is better with 4 of the same speaker or at least drivers. If you want to kick it up a notch. Look for an amp with a center channel output and give it a try. I found the system when properly set up to be better than the quadraphonic systems and can easily enhance the stereo experience without detracting.
outshined
Super Member
There are the rackmounts and also the 17" wide units. They are, of course, electrically identical. I have such a unit and it does have feet. I'm surprised there have been more rackmounts.:scratch2:
I never bid. I snipe...
http://www.esnipe.com
You will be high bidder more often and can place your snipe bid at anytime, for the amount you're willing to pay. Try it!
RawDeal
Active Member
Why Not a surround sound decoder
I have an Onkyo ES-600 PRO surround sound processor. I have it running a center speaker and a pair of rear. It has a built in 50watt amp for a single center channel speaker and a 20 watt per channel rear L & R. It has a setting for HALL or STADIUM, Dolby Pro Logic and Dolby Stereo. The HALL setting sound pretty good with jazz records you can adjust delay from 0 to 40 milliseconds. I have not played with it much yet though. $5 at a yard sale. They go on Ebay CHEAP. Very quick and easy. Movies sound very good through it. The PRO LOGIC setting only sounds good on movies. I don't have a manual so I have figured the thing out yet.
Is this not basically what a Carver C-9 does? Or am I way off base.:scratch2:
I have an Onkyo ES-600 PRO surround sound processor. I have it running a center speaker and a pair of rear. It has a built in 50watt amp for a single center channel speaker and a 20 watt per channel rear L & R. It has a setting for HALL or STADIUM, Dolby Pro Logic and Dolby Stereo. The HALL setting sound pretty good with jazz records you can adjust delay from 0 to 40 milliseconds. I have not played with it much yet though. $5 at a yard sale. They go on Ebay CHEAP. Very quick and easy. Movies sound very good through it. The PRO LOGIC setting only sounds good on movies. I don't have a manual so I have figured the thing out yet.
Is this not basically what a Carver C-9 does? Or am I way off base.:scratch2:
outshined
Super Member
The Carver circuit is entirely different than a pro-logic or DD decoding system. The hologram circuit uses only 2 speakers to broaden, widen, and deepen the soundstage.
A brief description: Both channels of a stereo signal will be heard by both ears, with about a .2ms delay for the right ear to hear the left channel and vice versa. This is due to the distance between the ears.
With sonic holography, the signal from the right channel is fed to the left channel with a .2ms delay with a rolled off high frequency. The same is done to the left speaker.
The signal from the right speaker will reach the right ear simultaneously with the unwanted acoustic crosstalk signal from the left speaker. The signal is phase inverted and delayed by .2ms and will cancel the signal from the left channel signal, which has been fed the phase inverted, delayed signal from the left channel.
So, in simple terms, the right ear hears only the right speaker, and the left ear hears only the right speaker. This is not like listening to headphones, as might be thought. This creates the perception of extreme depth and ambience, and preserves the spatial clues and position of the space in which the recording was made.
You may hear a sax, for example, 10 feet to the right of the right speaker. You may hear a flute another seemingly 10 feet to the left speaker. Sometimes, you will hear instruments in various positions around your room. Drums are always located dead center, where they should be.
One listen to Dark Side Of The Moon will have you wanting for more. This is how I feel about it, and I've been listening to holography for close to 30 years.
Even multi-mic'd recordings will have a very large acoustic space. Recordings that use just a few mics will sound their best, because, since each mic hears the other mics, the delayed, cross fed signals will be eliminated through the circuit, allowing the R or L ear to hear only that particular mic.
The effect will vary with each recording, but once it is heard, you will not want to listen to a flat, 2 dimensional soundstage anymore. I feel the effect is much better and more natural sounding than pro logic or other multi-channel circuits. It is extremely beneficial, however, when using surround sound like DTS or Dolby Digital.
The front channels huge soundstage, combined with the center channel for dialog and rear and side speakers will make for a truly "you are in the middle of the action" experience.
I refuse to listen any other way!
Hope this helps.
I finally got my C-9 today and am learning to set it up correctly.Part of me wonders whether this is working or not. When plugged in the little LED light illuminates. There are three buttons each of which can be pressed. I am assuming that the button that says "sonic holography" should be in the depressed position for the effect to work. Is this correct and should the other two buttons be depressed too?
Outshined you mention about the critical need for speaker placement. I like to sit about 16 ft from the speakers and I can place the speakers at their closest about 5 ft center to center since there is a TV in the middle. Presently they are about 6 1/2 ft apart and toed in towards my chair to form an isoceles triangle. What do you suggest I do?
Can I get a scan of the C-9 manual from anybody? Is there a CD available to help in the correct placement of the speakers?
All help is appreciated. Thanks.
Nash
Outshined you mention about the critical need for speaker placement. I like to sit about 16 ft from the speakers and I can place the speakers at their closest about 5 ft center to center since there is a TV in the middle. Presently they are about 6 1/2 ft apart and toed in towards my chair to form an isoceles triangle. What do you suggest I do?
Can I get a scan of the C-9 manual from anybody? Is there a CD available to help in the correct placement of the speakers?
All help is appreciated. Thanks.
Nash
outshined
Super Member
Nash,
There are a few things that must be done exactly as the manual states in order to achieve the full effect. All, or some, may not be practicle or even attainable for some, I hope this isn't your case.
First, the speaks should be placed on the arc of an equalateral triangle. I think you are too far from the speaks and the output is crossing too far ahead of your listening position.
I think you will need the manual to help you more than I can here. I can copy it for you, but since I don't have a working scanner, will have to snail mail it, unless someone here can help?
Some pointers: The speaks should be on the arc of an equalateral triangle.
The exact distance between the center of each speak should be the same, to within 1/4" to your listening chair. You can take a measurement from the top of the speakers front baffle or the baffle itself. Anywhere as long as they are equidistant to your chair (the back, top, or middle of the seat. I use the chair back, at the very top.)
Speakers should be a little closer together than "usual" Mine are about 4 ft. apart, and about 7 ft. from the back of my chair. (Not equalateral, but my room was purpose built for Holography) Move your speakers as close together as possible without blocking your view to the TV. Try moving your chair closer to them.
There should be at least 3 ft. of distance from any room boundary. This is very important. If you have floorstanders, this will be OK, unless the floor is very reflective. If you have carpeting, it's not much of a concern.
Once you have satisfied these criteria, play a recording that lends itself quite well to holography. (You can leave all 3 buttons in.) Some recordings I can recommend are DSOTM, (probably one of the very best), Blood Sugar Sex Magic and One Hot Minute by Red Hot Chili Peppers, Diamond life, by Sade (or any Sade), Phil Collins, "Face Value", Gary Moore, "A different Beat" Alan Parsons "I, Robot", "The Nightfly" and "Morph the Cat" by Donald Fagen. Just to name a few. Small Jazz ensembles, Classical recordings live will generally work well.
The effect is unmistakable the minute you hear it. If you can satisfy the set-up needs, you will be greatly rewarded.
Now, won't someone scan the manual for Nash? :thmbsp::thmbsp:
outshined
Super Member
Yes, don't know how I missed Whole Lotta Love, it IS a killer song for SH
I find that almost any song or cd benefits from Holography. Some albums may not be recorded in a way that makes a wide and deep soundstage, but they still benefit.
There are just too many to list. Thanks for adding the 'Zep song :thmbsp:
Thanks for the tips. You mention that your speakers are 4 ft apart. Are they radiating straight ahead or angled towards your chair? I will have to work around the room to get the desired effect or maybe just shift to another room. The reason why I have had the sytem in the family room for so long is that it is on a concrete slab as opposed to the other rooms as it sounds boomy in the other rooms on high volume. I listened to Dave Brubeck's Castillion Drums with and without SH and when up close could immediately hear the sound shifting outwards as you have described. So at least I now know that the unit is working. I have also hooked it up to the Tape in and out on my preamp as you suggested. If one were to leave it on all the time shouldn't one plumb it directly between the preamp and power amp?
It would be really nice if I could get a scan of the manual otherwise I would like to take you up on your offer of getting it by snail mail. I am in no rush.
Thanks.
Nash
It would be really nice if I could get a scan of the manual otherwise I would like to take you up on your offer of getting it by snail mail. I am in no rush.
Thanks.
Nash
outshined
Super Member
Nash,
My speakers are toed in. I don't know the exact angle, but I'd say about 35-40 degrees. Just a guess.
I'm glad that you have heard the effect. I think, with a little tweaking, you will be able to get it dialed in as best as possible. Sometimes certain things need a little change. I know people, in general, don't like change. I don't! But, some things are well worth it in the end.
I would still recommend you leave the processor in the tape loop. It will not see any gain this way; a desireable thing. I turn off my gear when I'm done. Some people leave it on all the time. James Bongiorno, legendary audio designer and co-founder of SAE, founder of GAS and SUMO, says "Turn it off!!" OK, he oughta know...
If I can't find it on the internet, I will scan my owners manual with the SH set-up at Kinkos or some other place and mail it. You can PM me with your address.
I will try and post a pic of my room today. It's in flux, but you'll get an idea of how my speakers are set up.
