Tubes Recommendation for McIntosh Preamp

Thanks very much @wescoman for sharing your experience, Very helpful.

I actually think the current sound is not bad with the stock tubes. I was told the unit was about 1 year old, but I don’t know how many hours did the previous owner put in on the unit,

I have no experience of what a bad tube sounds like. So I thought for my own peace of mind, I would try some new tubes. But it is so good to know that you are running the stock tubes for 5 yeas without any problem. That’s wonderful!

I might just leave it for a while and see how it goes!

Thanks!

I sort of remember a thread up not all that long ago by someone bitching about the quality of the stock JJ (I think they were 12 ax7s) tubes in his Mac (I cannot remember if it was an amp or a pre).  That was making me think that Mac was putting JJ small signal tubes in from the factory.  Anyway, fwiw, not too long ago I put some JJ 6SN7s in my pre, and I don't think they sound all that bad.

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. 

Great.  Thanks @glennewdick.