Phono Stage Amp

I crank the volume up just past half way and there tends to be distortion. Below half way the sound is incredible. The records sound better than the corresponding CD or, of course, DAC streaming.

We're missing some important info. What is the cartridge, Cary Audio mono block main tube amp and speaker in your system?

Volume knob position means nothing! Could be the phono stage and preamp gain is too high overloaded the power amp input. You need to know the total gain of the whole system and the sensitivity of your speaker to see what cause the problem.

with volume halfway up on the SLP-05 using an Audia Flight CD player the volume is very high and no distortion. So, when I say volume halfway it is to my knowledge of the system which doesn't help you much. But at halfway with the TT the volume is 3/4 of the volume of the CD but with distortion. The mono blocks are the CAD805 Anniversary.

Since CD played louder with no distortion, we can rule out possibility of preamp overloaded the power amplifier, and speaker sensitivity isn't the issue.

Only thing left could be cartridge or phono stage.

300mV output from the phono stage seem fine.

I checked alignment and the weight, and they seem fine.  

Do you have a spare cartridge?

If your phono stage comes with balanced XLR and unbalanced RCA output, use the RCA connect to your Cary slp-05 might provide a better result.

the Cary SLP 05 offers respectable measured performance from its unbalanced jacks. I was a little disappointed with its behavior in balanced mode, however.—John Atkinson

https://www.stereophile.com/content/cary-audio-design-slp-05-preamplifier-measurements

@jasonbourne52 

How do you explain this:

imhifiman: with volume halfway up on the SLP-05 using an Audia Flight CD player the volume is very high and no distortion... But at halfway with the TT the volume is 3/4 of the volume of the CD but with distortion. The mono blocks are the CAD805 Anniversary. 

However your current phono stage / cartridge match is DEFINITELY a problem; it’s just that you may be dealing with multiple issues here.

@mulveling

The root problem is WHY crank the volume up just past half way and there tends to be distortion.

If the M1 can’t provide enough voltage to feed the downstream components, then the preamp volume control should be able to turn all the way to max to add gain. It may increase noise level but not distortion.

Move the turntable and see how the system react will not cost anything.