Patchwork quilt home theater system

[Lance Advance]

I'd like to see if there is anyone here who has a stranger home theater system than I do. I worked for a number of years as a musician and live sound mixer, so some of the components are left over from that phase of my life.

The sources include a Toshiba hi-fi VCR, a Dish 301 IRD, and a cheap DVD player that the kids bought us last Valentine's Day.

I have an equipment rack sitting on top of the entertainment center. The rack contains a TEAC / Tascam Model One audio mixer, used mainly as a master volume control, a Furman PB-40 patch bay (think telephone switchboard from decades ago), and a QSC model 5.1 power amplifier.

The entertainment center contains two video screens, a 27" Toshiba TV and an old Commodore 1702 computer monitor. The Toshiba has an RF input, of course, and it also has Video 1 and Video 2 inputs - no S-Video unfortunately.

The main loudspeakers are Tannoy PBM-8 recording studio monitors. They amazed me the first time I heard them, and now, over a decade later, the affair continues. I replaced the low frequency drivers last year, and my babies are as good as new. The QSC amp can deliver a solid hundred watts to each of the Tannoys, and they can handle the power without breaking a sweat.

Decades ago, David Hafler, who founded Dynaco, discovered (or popularized) a method of deriving rear (surround) channel information from stereo program material. Hafler connected one side of a speaker cable to the left channel positive terminal on the power amp, and connected the other side of the cable to the right channel positive terminal on the amp. On the other end of the speaker cable, each of the two ends was connected to the positive (red) terminal of a rear speaker, and the two negative (black) terminals on the rear speakers were connected together.

I found an amazing deal at a second-hand store this week - a Yamaha CRX-M5 micro system with two beautiful little two-way bass reflex loudspeakers for under $100.00. I decided to incorporate the new Yamaha gear into the home theater system, and I also resurrected a Yamaha FX500 multi-effects device to add a very short (25 millisecond) delay to the rear channel signal.

The QSC amp has two 1/4" phone jacks per channel for output, so I made a cable with two 1/4" plugs on the amplifier end and one 1/4" plug on the other end, which plugs into the input jack on the FX500. I'll try some ASCII art:

Tip L -------------------------------- Tip

Tip R -------------------------------- Sleeve

I actually used professional balanced microphone cable to make the cable. Tip L on the amplifier end to the tip on the FX500 end uses the white conductor in the mic cable. The black conductor in the cable is connected to tip R, and on the other end of the cable, both the black conductor and the braided ground wire are soldered to the sleeve terminal on the plug. Note that on the amplifier end of the cable, there are no "sleeve" connections.

(I hope the preceding paragraph made sense - a picture surely would have been worth a thousand words!)

Our el cheapo quadraphonic home theater system has been up and running for about twenty-four hours now, and so far my emotions are somewhat mixed. The rear channel material is simply left channel minus right channel (with a short delay if I choose to select it), so sometimes things are very busy back there, and sometimes there is silence. It's too early for a detailed report, but I must say I was impressed with the sound of the latest Harry Potter movie!

Cheers,

LA

[Tomsoundman]

Cool Lance. I played with the phase rear channel stuff in the early nineties.

What about the WAF (wife acceptance factor)? Sounds pretty ugly and hard to control <but that doesn't bother me>. Just an issue at my house.

The Tannoy's sound cool in a home. I've heard those it two studios recently and even though I wasn't in the "mixing seat" for a long period of time, they sounded great.

Keep us informed.

[Lance Advance]

Components are small, so the WAF has not been an issue.

I stumbled on this in the early 90s as well. When I researched how it worked on the Internet (Unix shell account at SDSU), I discovered the secret of how the Thomson Vocal Eliminator works ;-)

Thanks for your reply.

LA

[Chris Blount]

I was using the Hafler surround circuit in my home stereo back in the 70's. It worked quite well for creating quadraphonic sound from stereo sources. Today it will work just fine with Dolby Surround encoded movies and you even will get full range surrounds.

But, it's a very outdated way of getting surround from 2 channels. Dolby Pro-Logic and Pro-Logic II are much better since they have steering circuitry and are very cheap.

[Richard King]

Ah, the Teac Model Two mixer. :D You would be amazed at the number of very well know studio guys, writers and producers who started out with that mixer as part of their their first "studio" package. I did several location recording jobs in the mid-late '70's using two of these ganged together. Attached is a picture of my rig from back then all set up and ready to record. I recorded to a Teac 3340 four track machine. The second recorder in the picture (Teac A-7300 half track) is being used as a sub mixer since it had a four input mic/line mixer built in. I used to pack all this gear in the back of my orange 1972 Datsun 510 station wagon (with orange shag carpet in the back) :lol: and head out to capture the music.

The Dynaco product was available in both prebuilt and kit form. David Hafler continued this with this marketing tradition with the formation of Hafler amplifiers. I purchased and assembled one of his first amplifier kits under the Hafler name (it didn't even blow up the house when I first plugged it in). Good stuff. While I never did the surround thing as you describe, I had several friends who did and it actually worked fairly well.

Back when I was in the business, Tanoy made some very nice (and very large and expensive) 15 inch coaxial studio monitors. They were probably the biggest selling monitors for studios in England at the time, rivaling JBL. I sold a few of them into some very large home stereo systems for corporate executive types in the pre home theater days.

I have some close to 20 year old JBL 4430 studio monitors as my front speakers. As with any speaker with foam surrounds, I also had to have some work done on my woofers a couple of years ago. The foam had rotted away to the extent that there was none left, so I had both woofers reconed. All is still working well since having that done.

Take some pictures of your set up and post them so we can all see.

[Lance Advance]

As a photographer, I'm golden eared ;-)

On the rack, top to bottom, Tascam / TEAC Model One mixer, Furman PB-40 patch bay, and QSC Model 5.1 power amp.

On each side of the rack, my Tannoy PBM-8 studio monitors.

On the left side of the entertainment center, top to bottom, DVD player, Toshiba Hi-Fi VCR, Commodore 1702 monitor, Dish 4000 IRD, Dish 301 IRD.

On the right side, Toshiba 27" TV.

I tried a couple of times to get a shot of the FX500 and the CRX-M5, but the glare was too scary - I'll try again tomorrow.

LA

[Richard King]

I misread your first posting and thought you had said the Model 2 mixer, which is why my post makes no sense. :lol: I have used the Model One in many projects in the past also. It is sort of the Swiss Army Knife of line level mixers. Here are a bunch of Model 1 mixers installed in a submix performing arts theater application....

[Tomsoundman]

I sold a few of them into some very large home stereo systems for corporate executive types in the pre home theater days.


My uncle had a home theater in the 70s that was cool even though I was about 10 or younger when it was setup. He had a Technics turntable, 20 some inch TV (that seemed big then) with antenna only, Altec Lansing 1604 or 1602's (Huge with horns) with a custom cabinet in a converted garage with 12 foot ceiling....


Oh to go back in time...
:cool:

[Richard King]

Altec Voice of the Theater with cellular horns mounted on top of a 15" horn loaded woofer cabinet. :D Altec 604's were a 15" coaxial speaker that was probably the most popular studio monitor driver at the time, often mounted in custom cabinets.