1960 Magnavox Concert Grand model 1ST800F rehabilitation

[electra225]

I have both good news and bad news. The good news is that I got the motor apart, cleaned, probably over-oiled, and back in the changer. The changer is back in the cabinet. Let me say right up front that working around the MPX on this console is a royal pain. I have it mounted slam in the way of anything I need to do. It is supposed to be mounted onto the cabinet back, which would make it nearly impossible to work around. The changer works well, drops records, shuts off after the last record, so I think I am okay there. The bad news is that there is apparently a bad connection on one of the input wires where it connects to the tuner. I repaired those wires in 2014. One of them fails to ground well, which causes a massive hum. There isn't enough wire to cut off and redo the RCA jacks. The record player sounds pretty good, but will definitely benefit from a new needle. The motor starts right up. The problem was not the upper bearing. It was actually the lower bearing. There is a steel ball in the lower bearing that was stuck, not allowing oil into the bearing. The felt appeared plenty oily, so I think that ball stuck and starved the bearing for oil over time. This changer has a really convenient method for getting the motor apart so you can clean it without having to remove or disassemble the motor. I don't want to have to pull the changer to repair those two wires, but I may not have a lot of choice.

[electra225]

I fixed the hum issue. Don't ask what the issue was.....

When the record player runs about two hours, I started getting a considerable amount of "wow". I thought at first I had a warped record that was slipping on the one under it. Not so. The only thing I can think of is that the spring that holds the turret in place on the motor shaft is mispositioned. The turret is slipping on the motor shaft. I'll pull the platter and check that.

[William]

It sounds like you have made progress, and I think I will send you all of my Collaros.

Bill

[danrclem]

I'm looking forward to the end result of the rehabilitation of the Concert Grand. I hope you find as much difference afterwards as you did with your Imperial.

[electra225]

The way the motor is oriented in this changer is both obscene and brilliant. There are no motor mounts. The motor is bolted directly to the motor board. The speed change mechanism is part of the casting on the motor. You would need to be LOTS braver than I am to completely remove the motor. They put a little plate on the lower bearing that you can remove, then the rotor will fall out after you remove the fan and turret from the upper shaft. I don't have another Conquest changer to see if this arrangement is unique to the Concert Grand or if all Conquest changers have this setup on the motor. The arrangement for holding the turret in place is the obscene part. You need three hands to make it work. One to hold the fan from turning, one to release the spring tension, one to position the turret. I have a manual for the changer. Maybe I should read it again. IT might offer an idea on the speed variation.

[electra225]

I don't have another Conquest changer to compare, but the Conquest changer in the CG and the Custom changer in the Imperial are very different. I don't know if the differences are in the changers found in Concert Grand stereos, or if all Conquest changers are like this one. There is a "manual" lever by the speed control where you turn the changer on. When you move the knob you turn the Custom changer on with, that knob cycles the changer. I mentioned earlier the differences in the motor.

I found that part of the "wow" situation may have been a mispositioned turret. The more pressing issue is the oil I left on the motor shaft when I re-assembled the motor. I mentioned earlier that I had probably over-oiled the motor.........

[electra225]

Yessir, letting an auto mechanic work on a changer may be called a fool's errand........

More oil is not necessarily a good thing. Lesson learned here is to make sure you get the motor shaft absolutely clean with no oil above the bearing. Also don't believe the scare stories you read about what a pain the turret is to deal with. Horsefeathers. Like taking candy from a baby, as the old saying goes. If you read the Collaro manual for the Conquest changer, it said to hold the fan with one finger, then grasp the turret "between the index finger and thumb", (possibly on the other hand?) turn it in an "anti-clockwise" direction, while pulling "gently upward" so as to "prise" the turret from the motor shaft. When you go back, you stick a finger from your left hand into the fan blades to hold the fan, then push the turret gently down while turning counter-clockwise. When you feel a little click, that will seat the spring on the boss of the fan hub. This little operation has cured the "wow" situation. Next challenge is to figure out how much tone arm weight I need. I know I need a new needle, but adding more weight makes this stereo sound better. I thought I had the tone arm pressure set at about 5 grams.

[electra225]

3.8 grams is where the tone are pressure is set right now, It plays 78's just fine at that weight. The needle for 78's is better than the LP needle. I can't get a diamond 78 needle for this cartridge from Gary, at least none is listed. This old stereo REALLY sounds good playing 78's. I have a 12" 78 rpm record by Benny Goodman. The audio is clean and crisp playing 78's. I think a couple of new needles will put us in the pink with this record player.

[Conelrad]

Yes, a pristine 78 is a wonder to play on a proper system. The wide audio range and lack of surface noise is amazing.

I have a limited selection of special broadcast (no compression used) discs, and it is like the artists are right in front of me.

D

[William]

The Collaro in my Columbia/Magnavox is similar to your Collaro in your photo. I have the manual flip lever to but my knobs are shorter and my tone arm is different. The sticker in the upper rear left corner of the changer is missing so I do not know what it said. I sounds like you made good progress and a new needle should wrap it up.

Bill

[electra225]

Dennis, to your comment about the audio quality of 78's. I personally feel 78's have better fidelity and are less noisy than 45's. I have a Russ Morgan album of 78's on Decca, IIRC, that sounds as good as stereo LP's. The Benny Goodman album I mentioned has his typical bells and xylophone that sounds clean with no ringing on the old CG. I've never had a 12" 78 rpm record before.

I didn't know, nor had I paid any attention, to the differences between the Conquest and the Custom changers, even though they are both technically F-200 model changers. My guess is that the changer mechanism is likely pretty much the same in both changers.

[Conelrad]

Thousands of classical 78's were made to accommodate the longer running time of movements, and so were lots of early WW2 AFRS records.

D

[TC Chris]

Theoretically, a higher speed analog disc is capable of higher fidelity. That's why inner grooves on LPs sound worse than outer grooves--more info crammed into less space on inner grooves. Think about the difference in circumference between inner & outer. Some of the high-end analog reissues are at 45 rpm (12" discs) and usually two discs where one at 33-1/3 had sufficed for the original. The limitations of traditional 78s are largely in the disc material--shellac with a filler of noisy crud--and the playback equipment, which was often a crystal cartridge.

7" 45 rpm discs were mostly intended for low-quality playback equipment and engineered accordingly--limited frequency range. My first 45 player was one of those little add-on RCA changers that played thru an AA5 with a 78 changer on top. Often the discs would skip--likely, in retrospect, from a low-compliance crystal cartridge and resonance issues with the stubby arm. They played better when I git the little RCA suitcase portable that's in my YouTube video.

Chris Campbell

[danrclem]

To me the 45 seems to have a better sound than a 33 1/3 record and that seems to be the thinking of most. Trying to buy used 45s is hard because almost all of them are in poor shape, but I do have some that are in excellent shape. I don't think I've heard a 78 since I was a kid so I can't comment on how I think they sound.

https://turntablewave.com/33-vs-45-vs-7 ... omparison/

[William]

Interesting link, Danny, thanks for sharing. I looked over their site but could not find where they are located. Did I miss something?

Bill

[Conelrad]

That guy is full of little brown turdlets about 78's and audio quality.

When they were pressed, it ranged from fine to excellent. Methinks his opinion is based on playing abused discs on a system not optimized for 78's.

Many examples of great fidelity exist, with hundreds here at the Radio Ranch.

D

[TC Chris]

Good response to that link. I thought it was filled with inaccuracies as well. He got the inner-groove distortion wrong, among other things.

Chris Campbell

[Conelrad]

This is truly the era of "idiots with keyboards".

[electra225]

I haven't owned many really good 45's in my time. A lot of mine came out of the jukebox at the American Legion in our little town. A buddy of mine's dad was the Commander of our local Legion and he knew I collected country music records. About 90% of the records in that old Rowe jukebox were country records. When the company who serviced the juke box changed records, I got the old ones. Lots of them were too far gone to use, so I tossed those. Jukebox records in that jukebox had a hard life. Many of them got played until they were so worn they were white instead of black in the grooves. As long as they played without skipping, they stayed. When they started skipping, they got replaced. Jukebox amplifiers must have had some kind of noise cancelling circuit in them, because the used jukebox records sure sounded better played by the jukebox than they did played on a home phonograph.....

[danrclem]

Interesting link, Danny, thanks for sharing. I looked over their site but could not find where they are located. Did I miss something?

Bill

I looked over it too Bill and couldn't find a location. With all the scams going on lately it might not even be a real place.