Mystere tube integrated amp

I have the Mystere PA-21 power amp. I'm currently using it with a McIntosh C22 preamp and Altec 846A Valencia speakers. I'm very pleased with the Mystere amp performance. I suspect you will like the integrated amp also
 
Thanks '69 Mustang. BTW, nice car. Interestingly, I see your in Chapel Hill, I'm 2.5 hrs away in Huntersville north of Charlotte. I'll need to take a run there sometime to hear your system.
 
Thanks '69 Mustang. BTW, nice car. Interestingly, I see your in Chapel Hill, I'm 2.5 hrs away in Huntersville north of Charlotte. I'll need to take a run there sometime to hear your system.
You're more than welcome to stop by - just let me know when you'll be in area.
 
No response from Lighty, but I just bought a Mystere PA-21 from Upscale. These are discounted about 30% and I believe these are no longer being made (could be wrong about that), so may not last long at this discount. From what I've read, great amp at a great price! I'll start a new thread when it arrives and burns in.
 
Sorry I never got back. The Mystere is a great tube integrated amp. I was surprised how tight the bass is, and how dynamic and detailed the amp sounds. Has a lot of qualities of a solid state amp.
amp.jpeg
rack wide.jpeg
 
Nice setup Lighty! Got my PA-21 and I have to say the PrimaLuna/Mystere Group's (Durob Audio to be exact) customer service is world class, right down to the white glove, triple boxed treatment!

I am using this amp to drive my Dunlavy HRCC-I center channel and a single KEF R107 rear speaker (I know, not really a purest use case). Why? Well I have a Rogue Stereo-90 KT88 amp driving my Dunlavy SC-IV mains and I wanted a tube amp that would meld with it and do the vocals justice. I figured a Pentode PP with EL34's would fit the bill nicely!

Right off the bat, even with re-stamped Shuguang KT88's, the PA-21 is one heck of an amp! It pushed a really nice McCormack DNA1 Deluxe right to the side and said, hey Rogue, lets party!

Can't wait to see how this evolves! I'm going to let the Shuguang 6sn7's and KT88's bed in and then I'll get some EL34's to roll in to see how they sing. So far I am one happy camper for just over $2K. If you can afford one of these (either the PA or IA), jump!
 
I agree, lot of quality and sound for the investment. I'm using lowly ElectroHarmonix EL34/6sn7 tubes throughout. I'm sure I can do better. It's good to know Mystere's factory tubes are Shuguang.
 
I agree, lot of quality and sound for the investment. I'm using lowly ElectroHarmonix EL34/6sn7 tubes throughout. I'm sure I can do better. It's good to know Mystere's factory tubes are Shuguang.

Nothing wrong with EH! I believe everyone who has reviewed the Mystere amps has noted that running them with EL34's is the ticket!

But yeah, from what I've read, they use top 10% matched tubes out of Shuguang. Mine are clear glass metal base KT88/6SN7's. I have a quad of NOS RFT (Siemens) EL34's and a pair of 70's Sylvania Chrome Top TB's coming. Be interesting to see what vintage tubes do for the sound.
 
Last edited:
SimplySound,
From my experience EH tubes have very good extension at highs and lows, but the highs can have a bit of extra energy though. While not necessary with Mystere's auto-bias (from PrimaLuna), my EL34s are matched from Upscale Audio. BTW the integrated amp only accepts EL34 unlike your power amp which also accepts KT88s. I little food for thought, there is an individual on Audiogon that runs the Mystere preamp. In our back and forth he commented on my system (which I deleted for some silly reason) saying it was the best tube preamp he's used and has had some really good ones.
 
Nothing wrong with EH! I believe everyone who has reviewed the Mystere amps has noted that running them with EL34's is the ticket!

But yeah, from what I've read, they use top 10% matched tubes out of Shuguang. Mine are clear glass metal base KT88/6SN7's. I have a quad of NOS RFT (Siemens) EL34's and a pair of 70's Sylvania Chrome Top TB's coming. Be interesting to see what vintage tubes do for the sound.

I've just put my Mystere PA-21 into System with a Yamaha C80 preamp and pair of Legacy Victoria LE bookshelf speakers. I had swapped in EL34 tubes previously. I find the combination sounds very nice. I think the Mystere is a very nice performing piece, which flies under the radar of most people.
 
I think the Mystere is a very nice performing piece, which flies under the radar of most people.
I agree with you Mustang, and at 30% off at Upscale an awesome deal!

I have gotten the Siemens RFT EL34's put in and man, I love the sound. It was just as I envisioned this would work. The EL34's driving the center channel has opened up the mid-range, smoothed out the top end vocal delivery and I think improved the bass depth. People have commented that EL34's make the bass bloated, but I disagree, I think it makes it sound like real bass! You can actually hear the "huff" of a Standup Bass!

I haven't swapped out the signal tubes yet, but it will be interesting to see what the Sylvania NOS tubes do for the sound. All I can say is there is a noticible change between the KT88's and EL34 output tubes.
 
Well I have the NOS signal tubes in now; Sylvania "green label" tall-boys in V1/V2 and "yellow-label" shortys in V3/V4. It has opened up even more with added detail. Not quite as noticible as the EL34 swap, but definitely a step up.

I guess that's why 50's & 60's NOS tubes command the $$$ they do! I'm happy with the vintage sound though, no reason going back to the stock Shuguang's! :music: :naughty:
 
Well, you know I had to try it; I put the Mystere in as the main for the SC-IV's and played it in Stereo mode!

It confirmed some of my original thoughts. With the Siemens RFT EL34's the Mystere doesn't drive as hard as my Rogue 90 with the Psvane KT-88's. But I think it has more to do with the higher input impedance of the Mystere compared to the Rogue (100kOhms vs ~70kOhms), rather then the nature of the EL34's.

What is interesting is the Mystere has more voltage gain in the output (~32db vs ~28db), but as John Atkinson determined in his measurements of the IA21, the output impedance of the Mystere is "interestingly" high, so that may have something to do with the drive from the amp.

Also, I now get Disk Olsher's TAS Review of the bass presentation. It wasn't as solid and locked in as the Rogue. I could also detect the roll off of the bass and of course the highs seemed a bit smother because of the EL34's. But the Rogue definitely is more dynamic (faster response) and that's another element Olsher pointed out with the Pentode output coupling design.

Bottom-line, the Mystere in my system is more suited to what I envisioned having it drive the HRCC center channel. It does voices so incredibly well with the EL34's. I definitely will keep the Rogue running the Fronts (mains), but I may experiment with rolling the KT-88's out for some KT-77's, that might be interesting!
 
I’ve been playing around with my systems this week and have ended up with the Mystere amp driving the EMITs and EMIMs on my Infinity speakers. I thought it drove my Legacy speakers very well, but concluded the McIntosh MC275 drove them better. I felt the bass was tighter, as well as fuller with the McIntosh amp. I do have the EL34 tubes in the Mystere, so may have driven the Legacies better with KT88 tubes - but I like the way it performs as is with the Infinities.


B403CC0E-9C40-4056-A25C-4D304F0F7E77.jpeg
 
Nice setup Stang! Would love to hear those Infinity's!

So it sounds like you determined pretty much the same thing as I did with the bass presentation of the Mystere. Not bad, just a little rolled off with some bloom.

So are you driving the bass with SS in those Infinity's? What amp? As they say, well played!
 
Last edited:
Back
Top Bottom