Has anyone run STR-415s and Shuguang 12ax7s in their reissie yet?

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Not yet. To start with, I do not have Shuguang 12AX7 (those look similar to the Beijing tubes but with a halo and not the square foil getter). I did not feel like pulling out the STR415 from the JP2C. What I did try (with my hearing impairment) was a full quad of STR448 (grey) power tubes. No bad. As for preamp stuffings. I did run a full set of the Beijing 12AX7 tubes. Then tried an RFT in V3 and the rest were Mullards. CV4004 V1, V2, V4 and a Mullard long plate balanced triodes in V5. Not bad but could not tell if things were better or worse. It would be best to wait for my hearing to restore itself. Just today I put back the original tubes and thought it sounded harsh (note that my hearing is more muffled so all of the midrange content is not audible.)

Just for S&G I wanted to see if the Faceplate I had removed from the Mark VII would fit in the Reissue. Nope. It probably would fit if I took off the metal corners. The piping around the faceplate made it nearly impossible to insert. However, I did sort of like the change, if it would have fit, I would have taken a picture.

As for the power tubes, Just try the STR415. What would be more accurate is to just use a pair of the STR415 in the center and leave the STR445 in the outer pair as they do have a similar sound to the 6CA7 tubes. The STR415 pins will be a bit small so they may feel like a lose fit. STR445 pins are on the large side. Perhaps when my hearing comes back I will get into tube rolling the reissue. May be interesting. Looking forward to hearing the STR415 tubes in the amp as well. At the moment, it would be wasted effort to do so until I can get the fluids to drain out of my ears.
 
I did just that. I ended up changing back to the stock 12ax7s but left the 415’s. The change was negligible to be honest, but the 415’s provide a more organized sound if that makes sense (to me anyway). The old 12ax7s I have (mesa square getters) were a little too raw. I didn’t try rolling them though, so maybe one or two would have been good somewhere.
 
In the Facebook Mesa owners group, there was a suggestion by a member Tony Batal to run
V1 = Tung Sol, V2+V4 = Mesa Chinese Beijing Square Foil getter (6N4-J), V3= RFT and V5=Sovtek LPS



I have the same preamp tubes in my box of stuff so I tried it. Left the power tubes with the STR445 (green, they were shorter than the yellows that were stock) Since I have hearing issues, I could not tell if there was much of a change. Bummer. That made me try running all Mullard CV4004 and a long plate Mullard 12AX7 in place of the LPS. STR448 (grey) as substitutes for the STR415 (did not want to remove them from the JP, waiting for hearing to improve).
 
In the Facebook Mesa owners group, there was a suggestion by a member Tony Batal to run
V1 = Tung Sol, V2+V4 = Mesa Chinese Beijing Square Foil getter (6N4-J), V3= RFT and V5=Sovtek LPS



I have the same preamp tubes in my box of stuff so I tried it. Left the power tubes with the STR445 (green, they were shorter than the yellows that were stock) Since I have hearing issues, I could not tell if there was much of a change. Bummer. That made me try running all Mullard CV4004 and a long plate Mullard 12AX7 in place of the LPS. STR448 (grey) as substitutes for the STR415 (did not want to remove them from the JP, waiting for hearing to improve).


Hey man, hope all is well.

The preamp tubes I suggested will make the amp sound more “clear” and the lower mids crunch sounds better with the German RFT tube. The most noticeable difference of course is V1. A Tungsol or C8 in there will open up the amp. But that depends on taste of course. I run these in every IIC+ original I own and it worked similarly on the Reissue IIC+.

What is your favourite for V1 so far?
 
I have shared a few things with Mr. Paul Azzi. I did recommend him to join the forums. I was the one who sent him a JAN/Phillips 5157 in hope to fix the issue he had with his reissue. Not to worry, mine does it too. Not that I am going to max out volume 1, treble and the lead drive with a high lead master. Running the amp with reasonable settings still sounds great. I can get the JP2C to push lots of feedback too but not without a guitar plugged in.
 
Hey man, hope all is well.

The preamp tubes I suggested will make the amp sound more “clear” and the lower mids crunch sounds better with the German RFT tube. The most noticeable difference of course is V1. A Tungsol or C8 in there will open up the amp. But that depends on taste of course. I run these in every IIC+ original I own and it worked similarly on the Reissue IIC+.

What is your favourite for V1 so far?
I did not get very far with tube rolling the amp. Shortly after getting it I lost my hearing as a secondary issue from having covid a week prior. Not the first time this happened to me. Just today, I was able to regain my hearing near normal so I can dive into seeing what works now. It has been at least 2 or 3 weeks, lost track of time how long I could not hear much if anything at all.
 
I did not get very far with tube rolling the amp. Shortly after getting it I lost my hearing as a secondary issue from having covid a week prior. Not the first time this happened to me. Just today, I was able to regain my hearing near normal so I can dive into seeing what works now. It has been at least 2 or 3 weeks, lost track of time how long I could not hear much if anything at all.
I am sorry to hear that man… I can’t imagine how this feels and I’m glad you are regaining your hearing now…

Have you had a chance to play an original Simulclass (DRG) IIC+? I did a video comparison on my YouTube channel against the Reissue. Some prefer the original, other the reissue. In the room, I vote day and night for the original as it has more clarity and note definition as well as much better lower mids compared to the reissue.

I was able to get the reissue to sound and feel closer to the originals somehow with the preamp tubes I recommended. The stock Mesa (JJ) 12AX7 make the amp sound more modern and darker. Which works well for rectos but not Mark amps, in my opinion.
 
Here is what I wound up with this evening. I knew I would be going at it once my hearing returned. Not sure what will tomorrow bring. But for now, this is the last tube roll. Power tubes: left as stock STR445 yellows.

V1= 1990 Mesa 6N4-J Military grade Beijing Square foil getter tube.
V2= Mullard CV4004
V3=RFT ECC83/12AX7
V4= Mullard CV4004
V5 = Mullard 12AX7 reissue long plate. Similar to the Sovtek LPS.

Made by Shuguang in Beijing. Production on those tubes ended in 1990 but there was a large surplus. After 1990, Shuguang closed the Beijing plant and moved to different location in southern China, Guangdong. The change in the 12AX7 moved from the square foil getter to a round folded halo. There were other changes to the design but it still looked the same.

Since the V1A and V1B (If Mesa followed through with the original design) that would mean the cathode bypass caps are 22uF or 15uF which adds depth to the sound on both triodes. Mesa branded ECC83s a bit on the blunt side and too warm with those values of capacitors. I am sure the Tung Sol 12AX7 would do fine in this position as well but I found the old Mesa tube to have a specific quality to it for the first gain stage. the next gain stage that gets signal is V3. I would agree with Tony Batal on this tube in the overdrive gain stage. Also helps tone down the reverb as that is also used for the reverb recovery stage. Now for a change. V4 with the Mullard CV4004. A different voice than the Tung Sol and more aggressive than the Chinse tube. I wanted to improve the grind from the amp a bit more. The 6N4-J was a little thin or neutral sounding. The CV4004, some may say is darker than the Tung Sol, it probably is, but it does have a slight scoop in tone and plenty of robust gain characteristics. The other triode of V4 is used as a driver for the reverb circuit. Why not keep things a bit on the aggressive side. V2 with the same Mullard CV4004 (matched triodes but not sure that matters here). Hammer that into a Mullard long plate reissue 12AX7 tube for the Phase inverter. Holy Hanna, this reissue can really rip. I still have that low frequency hum, but it is not something that is troubling. I had set up the JP2C on the other cab in the room. I did compare the two before I completed the tube roll and then after. Before I did anything, the JP2C was king in the grinder department. Now it sounds a bit weak after the change in preamp tubes. May have to see if I can revamp that amp too. I ran out of RFTs though. Not sure if the Mullards will work as the last time I tried them in the JP2C I had some issues with motorboating. Some of that forward midrange content got tucked in a bit. I felt it seemed to forward with the stock tubes.
 
After I got up this morning and still had my hearing, headed into the studio and made some noise. Yep, confirmed, the preamp tubes I stuffed in there are a go. Gold or holy grail of sorts, at least for me. Would like to find out what is causing the low frequency hum as the Reissue is noisy compared to the JP2C.
 

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