12AT7 comparison - Mullard, Stock Raytheon and Psvane

[Tom-Huffman]

Paul,
You asked me a couple of months ago to compare the stock Raytheon 12AT7 with the Psvane.  Because I also had a Mullard, I included it as well.
My system consists of Stereomour upgraded with Triad chokes and all AuriCaps + JJ 2A3s and Psvane 12AT7.
Speakers are Lowther PM5As in plexiglass open baffles and Great Plains 416s in the enclosure below the window tuned to 25Hz.  Electronics: First Watt B1 preamp, First Watt B5 xover at 120Hz, rebuilt Adcom 5500 for woofers.

Observations:
1. All three tubes are very musical.  If you did not do A/B/C comparisons you would be happy with any of them
2. The Raytheon and Psvane were most alike and more dynamic
3. Mullard was more veiled and less dynamic but very musical
4. This is when it got complicated comparing the Raytheon and Psvane
5. Raytheon had more clarity in the upper registers.  I noticed it on one track of Foreverly in the percussive section. 2 sticks were hit together, smaller than drumsticks and more like big hardwood chopsticks.  This is minor but easy to hear.
6. The Psvane had a larger soundstage and more articulation.  Articulation is the only word I could think of.  It sounded louder and had the greatest dynamics therefore giving more emotional impact. Plucked strings or drum strikes were very defined.
Remember my Stereomour is only used from 120Hz up.
Conclusions: the Psvane grabbed me the most. I found myself listening to one track after another even though I wanted to go to bed. This took me 3 weeks with some listening most every night and taking notes.
Take care,
Tom

[Moot]

Thanks for that, Tom! I think it was an earlier post of yours that made me try the Psvane 12at7 and I've been pretty impressed with it, too. Haven't gone back to anything else.

[jamesp]

I've been running my Stereomour for quite some time with a Mullard old stock and while it sounded quite good (Klipschorns) it never sounded great, there just seemed to be a holding back across the entire spectrum.  I recently purchased a couple of Sylvania 12AT7WA's (their Gold Series specifically made and labeled for the Air Force) with three extra heavy Mica spacers......my goodness, what a change.  The whole sound stage was like a veil had been lifted.  A very slight persistent background noise was eliminated as well, one that I really did not realize was there until it was gone, the Mullard had obviously been fairly noisy, perhaps just that tube (as opposed to the whole species).  Looking forward to more exploration but I would suggest getting your hands on one of these, they are going for only ~$18-$20 on E-bay but well worth it!

James P
No affiliation with anybody but my Wife (the boss)

[Guy 13]

I've been running my Stereomour for quite some time with a Mullard old stock and while it sounded quite good (Klipschorns) it never sounded great, there just seemed to be a holding back across the entire spectrum.  I recently purchased a couple of Sylvania 12AT7WA's (their Gold Series specifically made and labeled for the Air Force) with three extra heavy Mica spacers......my goodness, what a change.  The whole sound stage was like a veil had been lifted.  A very slight persistent background noise was eliminated as well, one that I really did not realize was there until it was gone, the Mullard had obviously been fairly noisy, perhaps just that tube (as opposed to the whole species).  Looking forward to more exploration but I would suggest getting your hands on one of these, they are going for only ~$18-$20 on E-bay but well worth it!

Hi James.
Welcome to the Club. I also have a boss, my wife.
Fortunately for me, she can't fire me, she needs me...

Guy 13
James P
No affiliation with anybody but my Wife (the boss)

[MWalt]

I compared the Psvane 12AT7 to a NOS Raytheon 6414 triple mica blackplate. IMHO the 6414 was better from top to bottom.

[Daikini]

Tom, I have a Stereomour with the same modifications and JJ 2A3's as you, but I'm running very different speakers (Klipsch Heresy II with Crites titanium diaphragms in the mid/squawker). 

I have tried the following 12AT7s or equivalent: Sylvania (shipped with kit), Westinghouse, Amperex 7062, and Mullard. Because of the tendency of the Heresy speakers to be harsh in the upper midrange and lacking in bass, I really latched on to the Mullard-- its warm sound seemed to help even out the speakers. However, after several months of listening, I started to feel that something was missing, and after reading this thread, I put the Amperex back in (it was my favorite before I got attached to the Mullard).  More clarity and better separation of the instruments seems to be the result, but that's just a first impression after a few days. 

I changed some other things in my system over the months that the Mullard was in (Grado cartridge in the turntable, different tubes in my Seduction, adding a second subwoofer and hooking the subs up to the Heresies along the lines of the SEXy speaker setup), and these changes seem to have lessened the need to mellow out the speakers. 

It's hard for me to be objective about tube rolling.  I think sometimes I just want to hear something different after a while.

Anyway, the point being that I agree that the Mullards tend to be lacking in clarity compared to other tubes.  But I would also add that they can have a beneficial effect in some systems that are harsh sounding or overemphasize the high frequencies.

 

[Tom-Huffman]

James P - I just ordered your recommended Sylvania and will see what my preference is with the Psvane. 
The Stereomour produces good music regardless!