Too Much Gain the Issue ? (preamp and amp)


I have a Cary SLP-05 preamp- 24db gain with balanced and 17db single ended.  

Using a Pass Labs XA30.8 (26db gain) and even with the 17db of the single ended output of the Cary preamp the sound can frequently be sibilant in the upper midrange.   

Have not had the sibilant sound with other amps (Parasound JC5) but did lower the gain on that amp to 50% of dial.  

Thanks.  

 

avanti1960

Preamp tubes are optimized- all spots have early 50’s Sylvania 6SN7 GTA. Smooth as glass.

Tried putting the EH, Ken-Rad and Raytheon in and no help.

OK, that's fair and sorry I doubted you! I have 1950s Sylvania 6SN7GTA in my collection, and can confirm they're smooth. I was hoping you were using EH because that would have given you an easy move in the right direction.

I roll several components in my main rig, and some combinations just don't work great for whatever reasons. Sometimes you can mitigate a bit with tube-rolling, but it's most important to find components that mesh well together. And it's not always JUST the amp & preamp pairing either - upstream (phono / SUT / cartridge) and of course downstream (speakers) are also big players in whether the whole system gels together. 

Buy a very low output MC cartridge to soak up some of your excess gain.

Buy some really inefficient speakers.

Most people would kill for the gain you have.

But the Cary preamp gain is mad high.

Hay @avanti1960,  I also own the Cary SLP-05 and my power amp is the Parasound JC5, which has an input gain dial for both channels.

There is no question that the output gain from the Cary is very high.   When I got my Cary earlier this year,  I was playing around by adjusting the output gain dials of the Cary and the input gain dials of the JC5.   

Parasound suggests the gain dials to be set a the maximum position whenever possible.  I do seem to agree with them.   I feel like I'm getting more bass, when the input gain dials are set at their max.

I finally settled on setting the output gain dials of the Cary at around the 3 o'clock position, and leave the JC5 input dials at max position.  I found that anything less than 3 o'clock on the Cary makes the sound a little lifeless.   Whereas setting them higher can sound a little bright on my system.

I'm pretty happy now with this settings.  My usual listening level is between 8 and 10 o'clock on Cary's volume dial.   It doesn't bother me that I can't use a wider range on the volume.  Anyway, the days of listening to loud music is over for me.  I need to preserve my aging hearing for as long as possible. 😀

BTW.  Cary support did tell me once that they have a gain reduction modification, which will bring the gain of the Cary down by 6db.  It costs $140 bench fee, plus labor and parts.   I didn't go for it.

Anyway, good luck, and hope this helps.

 

sibilant in the upper midrange - several issues can cause this

1-gain

2-bias adjustment

3-source

 

Happy Listening.