Zenith Console muffled speakers

[Madeline12]

This is more out of curiosity than an actual repair I’m doing.

As you probably remember, I was working on a zenith console. Still haven’t figured out what’s causing the 78 rpm detector to detect 78s when I have a 45 on. But regardless, I have ANOTHER Zenith console, MM2670, however I inherited this one from my great grandmother. I never plug it in anymore, as I am almost positive the can capacitors in the power supply are bad. However, I’m curious if the muffled sound from the speakers could be due to the bad can capacitors in the power supply. I know it’s a fairly broad question, as many things could probably be causing this issue. But is it possible these specific capacitors could be causing this? Eventually, I will bring it in to a shop to have it repaired, though that’ll be years. I feel comfortable fixing the turntable, as everything works with it, but I have to carefully clean it. It just runs slow. Hopefully this sentimental console of mine will be restored to its former glory.

 

[Madeline12]

Here she is by the way, quite a beast.

 

[vwestlife]

Maybe the tweeters are dead. Does it sound OK through the headphone or external speaker outputs?

 

[Madeline12]

Maybe the tweeters are dead. Does it sound OK through the headphone or external speaker outputs?

Unfortunately I can’t test external speakers due to the console having some issues with shocking me when I touch it, regardless if I flip the cord. Best not to turn it on I guess. And I don’t believe there’s a headphone jack. I’ll double check though and edit later.

 

[mashaffer]

Unfortunately I can’t test external speakers due to the console having some issues with shocking me when I touch it, regardless if I flip the cord. Best not to turn it on I guess. And I don’t believe there’s a headphone jack. I’ll double check though and edit later.

Looks like some basic service is in order. Time to scare up a schematic IMO.

 

[Gazdatronik]

Unfortunately I can’t test external speakers due to the console having some issues with shocking me when I touch it, regardless if I flip the cord. Best not to turn it on I guess. And I don’t believe there’s a headphone jack. I’ll double check though and edit later.

Looks like the death capacitor is doing its job

 

[bigaltx24]

Power supply problems are the first thing to fix. The muffled sound is probably from the tweeters not working because the crossover caps are bad too.

 

[Madeline12]

Power supply problems are the first thing to fix. The muffled sound is probably from the tweeters not working because the crossover caps are bad too.

Alright, so first step I imagine is replacing ALL capacitors. Makes sense, as what I’ve been told on here is that after a while they should be. I’m hoping that’s the only issue here. If I am to get this fixed in the next few years, the person I’ll bring it to charges by the hour. So hopefully it won’t take TOO long. But thanks for the response!

 

[Mikehook]

I know this is an old thread but i have a 1960 zenith console and im getting great sound from the cobra-matic TT and tape deck ports but the radio is muffled both am and fm . cold it be a bad ground with the radio? ive only fixed the tuner knob cord inside so far but moving into fixing the atomatic tone arm next .thanks for any suggestions in advance.

 

[bigaltx24]

Some consoles have a RCA or some other type of connecter going from the radio to the amp input. If so check for looseness and clean if possible.

 

[vwestlife]

Also check for out-of-tolerance resistors and open or shorted capacitors in the tuner circuit. Tube equipment is very forgiving of bad components -- it takes something very wrong for it to stop working entirely -- but they will affect its sound quality.

 

[raycarr00]

if it's tube based, might need new ones. 6 tubes used in my tuner section. 4 for the amp section. tuner section might share similar tubes that can be switched around. could need a good cleaning of the selector and other pots. a wire might need resoldering. if it's tube based, it's fairly reliable. I run a variety of preamps on it. sounds great with external-contemporary spkrs. have any pics of internals or a schematic?

 

[JR DePlateau]

Unfortunately I can’t test external speakers due to the console having some issues with shocking me when I touch it, regardless if I flip the cord. Best not to turn it on I guess. And I don’t believe there’s a headphone jack. I’ll double check though and edit later.

There's a headphone jack

 

[JR DePlateau]

Also check for out-of-tolerance resistors and open or shorted capacitors in the tuner circuit. Tube equipment is very forgiving of bad components -- it takes something very wrong for it to stop working entirely -- but they will affect its sound quality.

This is a solid state unit, I have an identical one

 

[cademan]

I had the same console design but I also know that the same designed cabinet had a few different units in them including tube, hot chassis, and solid state. Mine had a hybrid half tube and half transistor.

4 year old thread but who knows who may be watching.