Q Bias for Cary SLI-80


Cary co. says that proper bias for Cary SLI-80 is about 75mA.

But the allowed range of bias is from 75mA to 100mA.
Which one is the best from your experience?
I would share our information.

And, I heard that I can use EL34 or 6L6 outpu tubes instead of KT88/6550 and when using other output tubes, it should be same bias.

Is it right? If anybody knows it, please share it.

skyserve
The optimal bias setting will be different for each tube type.  KT88 and EL34 have different bias settings.  Check the tube’s specification for optimal bias setting. 
I have the SLi80 and recently found that increasing the bias to 90mA resulted in a significant change for the better (for my taste at least) in triode mode.  The upper mid and higher frequencies are more crisp and precise with improved firmness across all frequencies. In ultra linear mode, though, the sound became “glassy” and uncomfortable. 
That's the case. I used to bias vintage Mullard EL-34 tubes at 60-65 mA but soon replaced them with GEC KT-88s. First I biased the GEC tubes at 75mA as recommended but did not like their sound. Now they are biased at 65 mA and sound much more open and transparent without being bloated.
If you bias the EL34s at 75mA you will blow the AC fuse.  The Cary manual is unclear on bias settings for the different tube types.  75mA is good for KT88's.  EL34's should be biased at 50-55mA each channel.  I confirmed this with Cary.
I figured I would bump this thread to see if anyone has played around with biasing on the Cary SLI-80 preferably in triode mode and KT88's. Preferences/Opinions?

I'll echo Artmaltman's question above.
I tired EL34 on my SLI-80. EL34s are Antique Selections EL34 JJ Tesla Blue Tubes.

I adjusted bias as 90mA.

Sound is firmed up and more clear.
Very high sound is too musical, Bass is more tight!

It's big change! If you have SLI-80, try it.
Thank you, Rrsclyde!

Good information!
If anyone uses 6LL on the SLI-80, please share it.
emailing cary yields hit or miss responses. actually pick up the telephone and call them. you'll get a lot more information this way.
Thank you very much.
Good information!

Then, is it same bias for EL34, 6L6 like KT88?
(range is from 75 to 100 mA, right?)

I have already sent email withsame questions to Cary Co.
But they have few information for that. (I think they are lazy to answer it.)

Thanks !
After much experimentation with my old SLI-80, I found biasing at around 90 to be preferred. YMMV depending on speakers, etc.
hi,

I've used KT88's ( EH and JJ Telsa) and 6550's ( Tung Sol nos solid gray plates, and Phillips nos ) biased at 75 with good sound. The favorites of mine are the JJ's and Tung Sols.

I tried EL-34's and , well they are in a box and the Kt-88s are in the amp.

good listening,

Larry
i think you can use pretty much any octal based pentode in the sli-80. i'm using kt90 in my cary monos. i would suggest you adjust the bias within the range and see which you prefer the most. honestly, the best way to answer your questions is to call cary directly. the customer service there is great when it comes to answering questions.