Sylvania Exponent 4/40 Sound Issues

[cooljer]

I have been working on this unit for a few weeks. The problem I am having is with the sound ouptut from the Garrard turntable. The sound is fuzzy and distorted--especially on vocals. Some album tracks sound better than others but even then the clarity is not there.
The unit has a brand new ceramic cartridge & needle. I have played a CD player and a tape deck through the AUX inputs and the sound is great, crystal clear. I plugged in my headphones and got the same great sound.
The turntable through the headphones sounds the same as the speakers-bad.
Any advice on where to start looking would be appreciated. Thanks.

[Electronic M]

Check tracking weight of the tonearm against published specs for whatever cartridge you're using.

Also if you're replacing the original ceramic or crystal cartridge with the same model in NOS it's possible that most of that make and model are uniformly failing from age.
Rubber parts break down with age as can the piezoelectric elements...If a certain cart was only made for 2-3 years and they've all past the expected life of the perishable parts of the internals, then finding a good one NOS or used becomes similar to playing the lottery.
I often replace bad original ceramic/crystal carts with the ones the crosley reproduction players use because I'd rather spend $2 once and have it work than $40 2-10 times till I find a correct NOS part that isn't DOA from old age.

[cooljer]

Thanks for the info. I will check it out.

[zeno]

Shango has this up.

https://www.youtube.com/watch?v=e0DkojD6NBk&t=576s

I would check both cartridges specs. They vary wildly on output.
Odds are this one wants a low output cart. There is an Astatic
catologue on the net & surprisingly readable !
And yes NOS carts are going bad on the shelf. And other things
you wouldnt expect.

73 Zeno
LFOD !

[cooljer]

Is there a chance that this unit may take a magnetic cartridge instead of the ceramic I installed?

Thanks,

[Electronic M]

Originally Posted by cooljer

Is there a chance that this unit may take a magnetic cartridge instead of the ceramic I installed?

Thanks,

Unlikely for direct connection. Most ceramics are more than 10x the output voltage of a magnetic cart...So if you convert to magnetic you'll probably need to add a preamp.

[cooljer]

Ok, thanks.

[John Adams]

Originally Posted by cooljer

Is there a chance that this unit may take a magnetic cartridge instead of the ceramic I installed?

Thanks,

Good possibility the original was magnetic based on the results you are getting. Did it not have a cartridge when you acquired it? Do you have a resistor substitute box? If so hook it between the output of one channel of the cartridge and ground. Start high and start lowering the value and see what happens. It may attenuate the output, low enough that you will be able to determine that you need a magnetic cartridge instead of the ceramic you have installed.

[cooljer]

Yes, the cartridge/needle was a ceramic setup when I got it. Thinking that this was the problem for the distorted sound I purchased a new ceramic combo and got the same results.
This is a early model for the Exponent (1965?). The model number is 4/40-0. The Photofacts show a Astatic ceramic replacement part#. I seen other post that magnetic came along in 1966/67 with model 4/40-2.

[Electronic M]

Originally Posted by cooljer

Yes, the cartridge/needle was a ceramic setup when I got it. Thinking that this was the problem for the distorted sound I purchased a new ceramic combo and got the same results.
This is a early model for the Exponent (1965?). The model number is 4/40-0. The Photofacts show a Astatic ceramic replacement part#. I seen other post that magnetic came along in 1966/67 with model 4/40-2.

If the astatic Sam's for the 4/40-0 mentions is a ceramic look up it's data sheet and compare it's output voltage spec to the spec for the new cart you put in....If the new cart has a higher output voltage it could be overdriving the amp into distortion.

[cooljer]

Will do, thanks.

[cooljer]

Tom,
You might have a possible answer there. The original Astatic 181D cart listed in the Sam's has an output of .11v. The Pfanstiehl P-132D that was recommended has a replacement and was installed lists a .40v output. Would that difference be large enough to overdrive the amp?

[Electronic M]

Yeah nearly 4X input could definitely cause an overload. I'd be tempted to put a 50k pot or voltage divider circuit on the cartridge input to the amp for one channel and see if reducing cartridge output by %75 makes a difference in sound quality...If it does you've proved over drive and get to choose between finding a different cart that is a closer match or modifying it to scale down the voltage.

[cooljer]

Thanks for the quick reply. Not sure which way to go for now. I did find a direct replacement cart. EV-5562D which has the .11v output. I'll post the results once I'm done.

[cooljer]

Tried the 50K pot (left channel) and got the same result no matter where I set the pot. Should I look at getting the low output cart or is there something else to look at.
Thanks.