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Voice of Music Model 1450

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  • Voice of Music Model 1450

    Almost picked up one of these cosmetically-great little amps for $40 at a flea market. Connected a stereo speaker they had lying around, just to see if it powered up, and if it made noise. Took a cable to plug phone in to play music, to see if it made sound.

    I warned the shopkeeps that ANYTHING could happen with this thing, since nobody knows if it works, if tubes are bad, or if anyone tried to "see if it worked without a speaker connected". I told them that ANYTHING with tubes needs a speaker connected before powering up, or the thing could self-destruct. "Oh...we didn't know that. I think somebody DID look at it a few weeks ago." They were to have me plug into a power strip that had a couple things plugged into it. I asked if there was anything important plugged in, because there's a possibility of tripping the breaker. "Just a couple signs", they said.

    The thing had no power light (on the original unit), so one could only just look in back to see if the tubes started to come up (which is what I would do anyway) to see if it had anything.

    With nothing plugged into input, yet, and with speaker connected, turned it on. "Oh, good. Didn't trip the power strip, and the tubes are starting to glow!"

    Then, "OH SHIT!" The rectifier tube had sudden pulsed flashes, before I could get the switch turned off.

    "Hmmm...THAT ain't good!", I told the shopkeeps. I thought, "Well...maybe it just had some bad pin connections?" (but was pretty sure that wasn't it).

    So, I reseated all the tubes, checking the pins. They didn't look too bad.

    Turned it back on, and zilch. Nada. Nothing. Still, didn't trip the power strip.

    "It doesn't work", I told the shopkeeps. "I suspect it may have been plugged in before, without a load, and did just what I told you it would probably do if a load isn't attached".

    If I had just chanced it at a garage sale for less than $40, and brought it home untested, I sure would have checked things out first, and brought it up in a more careful manner. But, I had no tools, and wasn't gonna carry stuff in there with me, and I doubt they'd have let me disassemble the thing on the counter, anyway. So, only thing I COULD do is make sure it had a speaker connected, and roll the dice.

    They gave me a slip of paper to write a note on it, explaining to the booth renter what happened. Told him I properly connected a speaker, turned it on, and it fried. Left my phone number, asked what he wanted for it, now, since we know it is faulty. Not gonna give him full price!

    Anyway, if he calls, wonder if it's even worth $20-$25, not knowing for sure if the transformer is blown, or if it's something less troubling?

    Linked is the exact same unit (except this guy modified his). There's also a couple more videos on YouTube with this model. Seems like a snarling little critter, from those videos.

    https://reverb.com/item/917613-bouti...ss-a-blues-amp

    Thanks,

    Brad1

  • #2
    Originally posted by Brad1 View Post
    The rectifier tube had sudden pulsed flashes, before I could get the switch turned off.
    When you try to charge up old filter caps that have gone bad with age, that's exactly what happens. Not only is it a major insult to the rectifier tube, it can kill the power transformer. It's always always always a BAD idea to fire up an old piece of gear by plugging it straight into the AC line and "let's see what happens." This is why we first make sure the proper fuse is in the fuse holder, then use a variac to bring up the AC voltage slowly while monitoring the current draw on the AC line.

    Whether that VoM is still worth $20 or $40 is beside the point. It obviously needs fresh filter caps, and to be safe I'd replace the rectifier tube as one that has arced will probably arc again. It's a shame to let that happen especially if the rectifier is a classic like a Mullard, Amperex, GE, Sylvania or Telefunken. If you think it's a good chassis for your project amp, give the man his double sawbuck, or two, and get on with it.
    This isn't the future I signed up for.

    Comment


    • #3
      Originally posted by Leo_Gnardo View Post
      When you try to charge up old filter caps that have gone bad with age, that's exactly what happens. Not only is it a major insult to the rectifier tube, it can kill the power transformer. It's always always always a BAD idea to fire up an old piece of gear by plugging it straight into the AC line and "let's see what happens." This is why we first make sure the proper fuse is in the fuse holder, then use a variac to bring up the AC voltage slowly while monitoring the current draw on the AC line.

      Whether that VoM is still worth $20 or $40 is beside the point. It obviously needs fresh filter caps, and to be safe I'd replace the rectifier tube as one that has arced will probably arc again. It's a shame to let that happen especially if the rectifier is a classic like a Mullard, Amperex, GE, Sylvania or Telefunken. If you think it's a good chassis for your project amp, give the man his double sawbuck, or two, and get on with it.
      Well, I knew it was a gamble, explained that to them, and like I said...if I had picked it up for $5-$10 at a yard sale (which I would have paid, no problem, without even wondering), I would have brought it home, tested the tubes for good/bad, taken it out of the chassis and looked it over, and then brought it up on the variac. I just didn't want to drop $40 on a possibly totally-blown already unit, and they weren't going to let me take it home "to try". "All sales final!"

      I have a feeling it had been turned on before, with nothing connected, anyway. It just happened to finish its meltdown when I turned it on, I think. Those folks had no idea about these things, until I told them, and they said someone had checked it out before. "Did they connect a speaker?", I asked. Not that they remembered. That's when I explained that they should NEVER let anyone plug in a tube amp without a speaker connected, and found a pair of stereo speakers in the store, one of which I connected.

      I may go get it if the guy will let it go for $20. I do have some good old tubes of each type that it takes. Looks like a pretty cool little unit. May get lucky, and maybe it just needs new caps and tube(s) to work without blowing.

      Thanks,

      Brad1

      Comment


      • #4
        My 2 pence: With no signal into the unit, and the output section NOT oscillating wildly, there is no real harm to the output transformer/ with or without a load.

        Comment


        • #5
          Agree^^^

          While you SHOULD never power up a tube amp without a speaker, it isn't instant death. Ther is potential for ttrouble if a loud noise happens in the amp with no speaker, but for the most part, it just sits ther, and nothing is going on to make the huge transients that destroy transformers.

          I think of it like car seat belts. You should always wear the seat belt driving the car around, But if you are just sitting in the driveway saturday afternoon, listening to the football game, the seat belt is not necessary.
          Education is what you're left with after you have forgotten what you have learned.

          Comment


          • #6
            Originally posted by Enzo View Post
            I think of it like car seat belts. You should always wear the seat belt driving the car around, But if you are just sitting in the driveway saturday afternoon, listening to the football game, the seat belt is not necessary.
            Hijack: this reminds me of a true story.

            There was a drunk who came out of a bar, got into his car, and turned on the radio. He knew he was too drunk to drive, so he reclined the seat to take a nap as he listened to the radio. He ended up getting arrested for drunk driving even though the car wasn't even turned on... because he was drunk, sitting in the driver's seat and the keys were in the ignition.

            I don't know how the case played out in court. Seemed like a raw deal to me.
            "Stand back, I'm holding a calculator." - chinrest

            "I happen to have an original 1955 Stratocaster! The neck and body have been replaced with top quality Warmoth parts, I upgraded the hardware and put in custom, hand wound pickups. It's fabulous. There's nothing like that vintage tone or owning an original." - Chuck H

            Comment


            • #7
              That is not a single incident, this happens time after time in various versions around the country. Keys in ignition, and sitting in the drivers seat is considered intent. Just like a half-consumed quart of beer with the cap on it is still considered open alcohol if it is in your car.

              I had a kid working for me in Akron/Canton some decades back. We went out drinking one night at my hotel bar. I went to my room, he unfortunately decided to drive home. he realized he was too smashed to drive, so pulled off the road to sleep it off. The cops came up to the car and talked to him. They bought his story about being aware he should not be driving. They were in fact going to let him stay there. They told him to just go back to sleep and drive home later. In his confused state, they walked back to their cruiser, and he started the car and went to drive home. They then immediately busted him.
              Education is what you're left with after you have forgotten what you have learned.

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