Tubes Recommendation for McIntosh Preamp

Hi,  I recently purchased an used McIntosh 2-chassis C1100 tube preamp.   So far I'm pretty happy with it.    

I'm thinking about replacing the line level stock tubes.  They are 2 12AT7 and 1 12AX7A per channel.   

I'm looking for recommendation from fellow members here.   I would like something on the warm side (definitely not bright sounding), and good solid and tight bass.   

Also I wonder if I need matching.  e.g. do I need 2 matched pairs of 12AT7, with each matched pairs for each channel.  Or do I need matched quad of 12AT7 for both channels.   Same question for the 12X7A.  Do I need them to be matched.   I don't seem to see any information available in the user manual on tube replacement.

Thanks very much in advance!


Yes, most comments I read here in this forum mentioned that McIntosh uses JJ tubes in their tube components.  I actually have never heard of New Sensor mentioned by @wescoman.  

Nevertheless,  I guess McIntosh does a good job picking the right tubes for their product.  At least I hope so anyway.  😀.  Unlike Cary Audio SLP-05, I think most comments I read are negative with their stock tube made by EH.

I'm using some RCA 12ax and 7AT's not the most expensive tubes in the NOS market (I payed $25 each)but they have similar detail to the JJ stock tubes and have much better sound staging and bass control, not overly rich like some of the other NOS tube like the apprex and mullards. I have a really handy chart with sound characteristics of the 12 series tubes I'll see if I can figure out how to post it here its saved as a picture. 

I sent you a message with my email address i’ll email it to you i can’t figure out how to post it here. Ive also put it in my system pictures for anyone else. good for all 12 series small signal tubes like the 12ax7, 12at7, 12au7, etc. chart says 12au7 but they are all similar enough the charts good for all 12 series. 

Yeah. I did see your message, but when I went to click on it. It removed all the emails information. I don’t think they allow exchanging emails because they don’t want people doing business behind their back,

Actually I just clicked on your system, and I see the positing of the 12AU7 tubes.  Very nice thanks!

I also like your system, especially that cool Sansui tuner.  👍