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View Full Version : Avid Pellar and MC cart - distorted and muffled sound, but why?



terataz
07-02-2018, 17:36
Hi i've got myself an Avid Pellar phono pre-amp which i normally use with a mm cart.

Recently I've bought an mc cart, Audio Technica AT-33ptg/ii .

I've aligned the cart using the Technics Arc protractor present here https://www.vinylengine.com/cartridge-alignment-protractors.shtml (my tt is a Technics 1210)

and set the switches on the phono to MC (as suggested here http://avidhifi.com/images/pellar_manualv1.1e.pdf), then I've pressed play.

All I could hear was a very muffled, distorted sound. I've tried various switch combination, mounting and remounting the cart, but no luck.

Then i've read again the manual and noticed that while the input resistance in the phono input is at 47K Ohms, the cart has a DC resistance of 10 Ohms (https://eu.audio-technica.com/cartridges/AT33PTGII).

Now, i know that by using loading plugs I could match the resistance for a better sound, but after checking on different forum, i've assumed that was suggested, but not strictly necessary and i should at least be able to hear a clean, decent sound.


What do you guys think? Could that sort of distorted sound be an issue with alignment or really be something to do with different resistance?


I've had the cart checked by a friend and it's fine.

Stryder5
07-02-2018, 18:42
Are you using the lower pair of RCA's the upper pair are for impedance matching, why this should make a difference I don't know.

If this was new you should have some 500 ohm impedance plugs?

Have you set up the dip switches correctly left hand should be on and right hand to MC.

DiveDeepDog
07-02-2018, 19:01
I use 100 ohms with AT PTG ii, don't know if you can adjust settings or need to use loading plugs?:scratch:

Beobloke
07-02-2018, 19:08
To clarify, have you set the gain to 'MC high' (i.e. only switch 1 on each channel set to on) and fitted the 500 Ohm loading plugs?

47k on most MCs will make them sound a a bit flat and lifeless, but it shouldn't be muffled and distorted.

Barry
07-02-2018, 20:58
I take it you haven't got the input and output mixed up? It can happen to the best of us.

jandl100
07-02-2018, 21:12
If the alignment is anywhere near correct it should not be distorting like that. Sounds like it might be an overload issue.

Are you perhaps going from the phonostage output into your preamp phono input rather than a standard line input?

Stryder5
08-02-2018, 18:13
No feedback? Did you solve the issue?

terataz
08-02-2018, 20:23
Sorry for the late reply folks and thanks for the many great replies.


I'll address all questions:

1. I'm using the lower pair of inputes, although i've tried the upper ones (loading inputes)
2. I do have the 500 ohm impedance plugs, but i've not used it. My understanding was that impedance "refine" the sounds, but can't cause such "distortions" (as Beobloke confirm on his reply)
3. I've set the switches for MC low (manual state that's for cart from 500uV to 3mV, the AT is 3mV)
4. I've not mixed in with out BUT I was using the TUNER channel in my amp

I've since swapped the phono to the AUX input (in the LINE channel i have my digital source), and even with my humble mm Ortofon 2 Blue the sound has improved.
No more distortion on some of the high piano note.

I've also returned the AT cart a couple of days ago for fear it might have been defective or not compatible (silly i know)!
I'm getting a new one this week and i'm going to give it another go then. I've also ordered a scale to help with the setup.
I'll report once tested.

Thanks again for all of your comments and suggestions!

terataz
09-02-2018, 10:18
*UPDATE*

The original cart was checked under the microscope from the guy i've bought it from and he confirmed that during the shipping the stylus came off ! :stalks:

I guess that explain a few things now ....

Thanks again for all your help

jandl100
09-02-2018, 10:26
:doh:
:lol:

Muffled distorted sound.
Yup!!

Bigman80
09-02-2018, 11:25
Should have bought Angus' audio Technica