Magnavox Concert Grand Score

[Horn Head]

Thanks Raul!!

Get this.....this console is SUPPOSED to have those two different woofers. Thanks to Raul for sending Service manual info.

In the Specifications section it notes that:

- Bass Speaker CH1 15" PM 50oz 8 ohm P/N 584140-1
- Bass Speaker CH2 15" PM 35oz 8 ohm P/N 584130-1

That's just what this unit has....although the two speakers were actually installed flip-flopped (the 140 on CH 2 and the 130 on CH 1).

Strange this is.....never saw mixing speakers like this for a stereo unit.

Two more notes of interest:

1) The manual/schematics do indicate there were supposed to be dual 5U4 rectifier tubes, mine only has one (and that's despite the tube placement diagram from inside the console noting a "5V3" mod - indicating should have single 5Y3 rectifier tube).

2) I was mistaken about this having no MPX unit. It sure does. It's underneath the tuner and tuner power supply. It just doesn't have the remote control unit.

Again, thanks Raul for the assist. I feel better now knowing this really hasn't been tinkered-with too much. Still think the CH 2 amp had some work done to it though.

 

[djnagle]

I am envious!!! I have been looking for ANY tube consol just for the amp. I have no qualms about taking a chain saw to a consol for the bit and pieces I could get out of it, but in this case...... I'd totally disassemble it and make it concourse. Great find: it's not just cool, it's history.

 

[Sam Cogley]

Get this.....this console is SUPPOSED to have those two different woofers. Thanks to Raul for sending Service manual info.

In the Specifications section it notes that:

- Bass Speaker CH1 15" PM 50oz 8 ohm P/N 584140-1
- Bass Speaker CH2 15" PM 35oz 8 ohm P.N 584130-1

That's just what this unit has....although the two speakers were actually installed flip-flopped (the 140 on CH 2 and the 130 on CH 1).

Strange this is.....never saw mixing speakers like this for a stereo unit.

Two more notes of interest:

1) The manual/schematics do indicate there were supposed to be dual 5U4 rectifier tubes, mine only has one (and that's despite the tube placement diagram from inside the console noting a "5V3" mod - indicating should have single 5Y3 rectifier tube).

2) I was mistaken about this having no MPX unit. It sure does. It's underneath the tuner and tuner power supply. It just doesn't have the remote control unit.

Again, thanks Raul for the assist. I feel better now knowing this really hasn't been tinkered-with too much. Still think the CH 2 amp had some work done to it though.

Different woofers in each channel? That's weird. Hopefully someone here knows why it was done, I'm curious.

 

[TheRed1]

Magnavox's 1-ST800 model is listed on Billboard's 1960 Phonograph directory and also in their 1961 mid-season (read Christmas) directory. The price is initially $1,250 but was dropped to $995 by the mid-season listing. To view Billboard's Phonograph directories do a Google book search for the model number "ST800".

I suspect that the 1-ST800 model number was for the French Provincial cabinet since the dimensions listed for it are slightly larger than the 1-ST801 which probably encompassed the Traditional and Danish Modern cabinets. The greater variety of finishes available for the 1-ST801 also points to that conclusion.

Too bad you don't have the remote but I remember reading somewhere on AK that somebody supposedly had a case of NOS remotes for the Concert Grands.

That is odd that Magnavox used two different woofers. Are the bass amp circuits identical?

 

[mashaffer]

Do the two woofer chambers have different volume. Different magnet implies (all else being mostly equal) different Q.

mike

 

[tubeboob]

What a sweet piece.

Man, tube monoblocks . . . wow!!

I should be that lucky.

When you have them all up to dated, hows about a review?

Would love to get your impressions on them.

Cheers

 

[Glassweights]

Magnavox's 1-ST800 model is listed on Billboard's 1960 Phonograph directory and also in their 1961 mid-season (read Christmas) directory. The price is initially $1,250 but was dropped to $995 by the mid-season listing. To view Billboard's Phonograph directories do a Google book search for the model number "ST800".

Closest I can get to putting this is perspective: My first car was a 1964 Plymouth Belvedere and I saw an add in that years Nat'l Geographic showing it at $2000.

(I had spent about that much rebuilding it in 1975, so I was kinda surprised!)

Dan

 

[coffee123]

Closest I can get to putting this is perspective: My first car was a 1964 Plymouth Belvedere and I saw an add in that years Nat'l Geographic showing it at $2000.

(I had spent about that much rebuilding it in 1975, so I was kinda surprised!)

Dan

Ive got a cube of 486-33mhz processors I glued together. Looks awesome, but if ya think about it, its prolly $12,000 worth of processors back in the day.

I love this thread, learning all kinds of crazy things about that big maggie...and that tube organ??!! wow

Mark

 

[Horn Head]

Too bad you don't have the remote but I remember reading somewhere on AK that somebody supposedly had a case of NOS remotes for the Concert Grands.

That is odd that Magnavox used two different woofers. Are the bass amp circuits identical?

Red1, not only would this need need the remote control but I'd suspect it would also need the Wireless Remote Receiver inside the cabinet....I believe it would be located in the lower position in the middle of the cabinet - like shown by Randy Bassham's picture of a Concert Grand in the thread "1957 Magnavox console Stereo". His has a big piece of tube gear where mine has only a little MPX unit (and he mentions he doesn't have the multiplexor unit).

As far as I can tell from looking underneath the amps, the bass circuit is the same. The schematics don't indicate two different circuits used for the 82-01-11. I'll check closer though.

Also appreciate the info about the cabinets - will google for that info also.

 

[Horn Head]

Do the two woofer chambers have different volume. Different magnet implies (all else being mostly equal) different Q.

mike

Mike, There's actually only one big chamber for the speakers - you just can't see it well in the pics. Underneath the tuner is a tunnel (about 1'x1') that connects the the left and right chambers - kinda makes a big "U" shaped, sealed speakerbox.

Got to speculating about the two-different-woofer-design and maybe the two work in some kind of funky tandem like you'd use a passive radiator (but perhaps that's a real stretch).

I'd love to talk to the guy who came up with this design to know what Magnavox was doing....it is deliberate...but not intuitively obvious why. Very strange.

 

[Sam Cogley]

Red1, not only would this need need the remote control but I'd suspect also it would also need the Wireless Remote Reveiver inside the cabinet....I believe it would be located in the lower position in the middle of the cabinet - like shown by Randy Bassham's picture of a Concert Grand in the thread "1957 Magnavox console Stereo". His has a big piece of tube gear where mine has only a little MPX unit (and he mentions he doesn't have the multiplexor unit).

As far as I can tell from looking underneath the amps, the bass circuit is the same. The schematics don't indicate two different circuits used for the 82-01-11. I'll check closer though.

Also appreciate the info about the cabinets - will google for that info also.

Since the FM stereo standard was only approved in April of '61, any MPX unit in a 57 console would have been added later - and could have been one from any brand.

 

[tensleep]

Wild guess here, but I would expect that one woofer is able to reach lower in the audible frequency range and the other is able to reach higher into the midbass range. This will probably yield a smoother, more extended frequency response for the whole speaker system.

 

[Horn Head]

Wild guess here, but I would expect that one woofer is able to reach lower in the audible frequency range and the other is able to reach higher into the midbass range. This will probably yield a smoother, more extended frequency response for the whole speaker system.

Suspect this is indeed the case. A short tap on the cones yields a significantly lower resonant tone on the one with the bigger magnet.

 

[coffee123]

Since the FM stereo standard was only approved in April of '61, any MPX unit in a 57 console would have been added later - and could have been one from any brand.

Nope, my 59 Magnavox Imperial french provincial has the MPX unit, from the factory. Some of the models had the MPX device even before FM was transmitted in stereo...if ya search this site, i think you can find some back to 57 with MPX's.

Mine was also setup for a remote. But it was a wired device from what I can tell. A volume control as the remote panel has RCA's that would go inline with the ones from the preamp, and there was an extra solonoid on the turntable that would activate the reject mechanism. So a reject function was also part of a wires remote. But i have no idea what a remote would look like as no one has any info on it.

I just with it had 2 monoblocks, hehe

Mark

 

[Horn Head]

Nope, my 59 Magnavox Imperial french provincial has the MPX unit, from the factory. Some of the models had the MPX device even before FM was transmitted in stereo...if ya search this site, i think you can find some back to 57 with MPX's.

Mine was also setup for a remote. But it was a wired device from what I can tell. A volume control as the remote panel has RCA's that would go inline with the ones from the preamp, and there was an extra solonoid on the turntable that would activate the reject mechanism. So a reject function was also part of a wires remote. But i have no idea what a remote would look like as no one has any info on it.

I just with it had 2 monoblocks, hehe

Mark

Mark, In 1960 CGs, the wireless remote receiver provided Search, Tune, or Reject, Loudness Increase, Loudness Decrease, and ON-OFF Function (from the Service Manual Spec Sheet). Would also like to see a pictue of the remote Transmitter box - porbably as big as a shoe box! (But smaller than the remotes my dad had when I was little, i.e seven youngsters running around the house waiting for the verbally activated signal to turn the station....although we didn't need replacement tubes, we did require bread an water occassionally and maybe a bath before church.)

Before I scored the Concert Grand I was searching for the model on the net and came across some of those Imperials - the ones with only one biamp. Even though the pics I saw had the metal grill only on the middle slider panel and regular fabric over the speakers, I started wondering if the one I saw in the shop was truly a CG. The Imperials look so much like the CGs. But as the story played-out...went back the next week and the brass plaque on the front boldly stated "Concert Grand". Double checked the backside for the dual biamps and was in heaven.

And, looks like mine is a 1960 model and has the MPX - seems original. So Maggie was looking forward with installing soon-to-be-used upgrades OEM....great work by those folks.

 

[jaymanaa]

In the early days of "stereo", manufacturers did all sorts of things that seem crazy now that stereo means to identical channels. Motorola had the three channel amps and Magnavox seemed to like EQing the signal into multiple amps. I'm not really surprised to see the different woofers. What a beauty you have there.:thmbsp:

 

[ke4mcl]

i have a 1958 concert grand in mahogany. it uses two different amp chassis numbers with the same topology, (4) 6v6 for the woofer and (1) 6v6 for the horn. the woofers on my unit are different also. one seems to be for deeper bass the the other as its built more like a sub than a full range.

i rebuilt both of my amps and they sound great. the factory magnavox preamp/tuner sucks though. i did find that most mac preceivers like the mx114 fit nicely in the stock hole and look ok.

heres a link to scans of the owners manual and other docs that came with my concert grand.
http://s31.photobucket.com/albums/c386/secretagentxxx/magnavox concert grande docs/

 

[Randy Bassham]

Destroying one of these is like finding a Shelby Cobra, pulling the motor and transmission to finish your 85 Mustang street rod. IMHO the Concert Grand is one of the very few console stereos that has a real potential to take off in value. Right now they can usually be found pretty reasonable I consider them to be a good investment along with the fact that I just love the beasts. Destroying one of them for the components in my opinion is short sighted at best.

I like to listen to classical music on mine "LOUD". Before you try to match wits with the engineers that designed and built the thing take a good long listen to one that's restored just back to factory specs. I have put jacks on mine to play CD's, put on Josh Groban's "Jesu joy of man" or better yet a good recording of Bach's Tocatto and Fugue in D minor, crank it up...high as you can stand it. Listen to the brass coming from those horns, then the lowest organ notes, the power supplies on each power amp with it's pair of 5U4's can supply all the power the 16 6V6's need to sustain a bass note till the nails pop out of the walls. Now, turn it down and listen. The bass is just as deep and and highs are still clear and crisp, just not as loud. I really like all kinds of music and sometimes I pull the Iron Butterfly LP Inagaddavida that I bought 40 years ago and spin it up. GAWD I love that set. I have to do that when my Bride of 39 years isn't home.

I was a Magnavox Technician from the late 60's through the end of the 70's and had wanted one of them since I saw my first around 1971, I finally was able to find an extremely nice one. I bought it from the original owner, he gave me the owners manual and bill of sale but he'd lost the remote control hand unit, I now have one. He'd paid $1500 for it in 1961. The trip was a little over 1000 miles over a weekend but it's mine, mine I say....all mine.

 

[DanO55]

Drooling here. Thats the one we all should have to show off to our friends. You should be a proud papa.

 

[Horn Head]

i have a 1958 concert grand in mahogany. it uses two different amp chassis numbers with the same topology, (4) 6v6 for the woofer and (1) 6v6 for the horn. the woofers on my unit are different also. one seems to be for deeper bass the the other as its built more like a sub than a full range.

i rebuilt both of my amps and they sound great. the factory magnavox preamp/tuner sucks though. i did find that most mac preceivers like the mx114 fit nicely in the stock hole and look ok.

heres a link to scans of the owners manual and other docs that came with my concert grand.
http://s31.photobucket.com/albums/c386/secretagentxxx/magnavox concert grande docs/

Ke4, Thanks for adding the documents. Interesting to hear that your '58 unit came with two different chassis numbers too. Wonder if that's deliberate like the deal with the different woofers.