Too Much Gain the Issue ? (preamp and amp)

i am willing to try attenuators but are they any more effective than the front panel level controls?

Evidently, those level controls on the front your pre are not helping. You have nothing to loose by buying a pair of Rothwell Attenuators and putting them in the inputs to your amp. As far as the sibiliance is concerned, try swapping tubes.

Maybe, if you give Cary a call, they may give some advice on how to remedy the problem. This may be the best course of action.

+1@pmm.  When the (10dB) attenuator is used between the preamp and the power amp, quote (in Rothwell) "... not only is system gain reduced by 10dB but also the signal to noise ratio is improved by 10dB.  This pushes the noise floor down enough to create an inky black silent background from which the music can emerge with better resolved fine detail and transparency. This applies to even very high-end and very expensive pre/power amps." end quote.

Harrison Lab carries -12dB rca inline attenuator too and has good feedback but no xlr.  Also, I have used the variable attenuator a bit more expensive though.

After some interconnect cable swaps, using the single ended 17db output and adjusting the level controls on my preamp to 3/8 of a turn the sound is now very good and at times excellent.  

I have ordered a pair of Rothwell 10db balanced attenuators so I can use the balanced connections again and that should improve the sound even more. 

Thanks again for all suggestions. 

 @avanti1960 good! Nice effort to make it work!!! It’s an excellent amplifier. 

@audphile1 

thanks!  

as an update to this thread the sound was decent with my cary slp 05 preamp feeding the pass labs xa30.8 by compensating for the gain missmatch using the single ended outputs and lowering the level controls to aprox 30 percent.  the preamp single ended gain is 17db while the balanced gain is 24db.  

the sound from the balanced connection was unrefined and unacceptable no matter what i tried. 

however the single ended output seemed to lose much of the magic.  it was still not as refined sounding as i like, the soundstage was smaller and lower in height, possibly because the balanced out goes through another tube stage and dynamics were not as good, possibly by throttling the preamp level controlls too much. 

i bought some rothwell xlr attenuators which reduces the balanced output by 10db, down to 14 db net gain.  

this did the trick with no apparent negative impacts to the sound.  the huge sound stage and dynamics are back along with a more refined sound.  

moral of the story is that too much net gain between preamp and amp has a bad influence on sound quality.  

i am not sure how to make a rule of thumb but 44db total gain is about perfect and i have had success with 39 db net gain with other systems and now 40 db with my current attenuated system.  50 db net gain is definitely too much and 35 db is too little and anemic.