[jonathan c]

As a preamp I liked some 12AU7s, but for headphones (or as an integrated) they seem a little relaxed. It might just be the gain difference. NOS RCA 6201s have been the best match for me. I’ve tried some new 6SN7 just to check function, but have stuck to NOS RCA 12SN7 and the 12SX7 it came with. For me, changing the big tubes has had less impact on the overall sound. So I just stocked up on a few and called it good. It’s easy to drop crazy money on a bunch of tubes if you’re not careful.

• I like the idea, the parallelism of matching 12SN7 tube pair with 12AT7 tube pair in LTA MZ3. Perhaps “consistency is the hobgoblin of [my] little mind”: 12 volts throughout, no adjustment or conversion.
• There are wonderful specimens of 12SN7: RCA ‘narrow gap plate’, Sylvania ‘yellow print’, and from Japan - Hitachi ‘black plate’ for example.
• AND a 12SN7 tube is substantially lower in price nowadays compared to its direct (same brand / maker) 6SN7 equivalent.
# As for 12AU7 tubes, because of their 20x gain (versus a 60x gain for 12AT7 tubes), they are well suited for preamp and phono preamp use where lower amplification and much lower noise floors are requisite. In LTA MZ3, using 12AU7s might produce a docile sound.

 

[jtnt]

He mentioned the new LTA DAC in production and mentioned it uses the same AD R2R chip as $6K AudioNote DACs.

To add one bit of clarification, our DAC to be released sometime next year uses the same R2R chip AudioNote uses in their 6-figure $ DACs. And our DAC, while pricing is still TBD, will be a low 4-figures $ DAC.

 

[ThanatosVI]

To add one bit of clarification, our DAC to be released sometime next year uses the same R2R chip AudioNote uses in their 6-figure $ DACs. And our DAC, while pricing is still TBD, will be a low 4-figures $ DAC.

Looking forward to the Final product

 

[jonathan c]

To add one bit of clarification, our DAC to be released sometime next year uses the same R2R chip AudioNote uses in their 6-figure $ DACs. And our DAC, while pricing is still TBD, will be a low 4-figures $ DAC.

….two figures on either side of the “.” ?

 

[hifitoaster]

12SN7: RCA ‘narrow gap plate’, Sylvania ‘yellow print’

I'm still looking for a pair of the Sylvania 12SN7 Yellow Print Anyone have lead on some?

 

[Killerb]

Last night I skimmed all 46 pages of this thread looking for tube suggestions. I made notes.. a lot of notes. Then I went off to see what tubes I could find for sale on reverb, ebay, etsy, tube seller sites, etc...

To be honest, I'm a little lost and overwhelmed. I contacted a guy who's sold me tubes in the past, he has some Philips Heerlen pinched waist 7062 E181CC tubes, they are rare so quite pricy ($125 each). I could maybe get a pair of them. I have a single in my Bottlehead Crack. I'm also poking around all over the internet to see what I can find. Tubes are confusing with all the re-brands and different getters and such.

I've been looking at Brent Jessee tubes as well http://www.audiotubes.com/12at7.htm
The Tele and Mullard descriptions seem like something I'd like to try. I guess I could call Brent and LTA and ask for suggestions.

Should I get the pair of E181CC tubes? How about a pair of 12SN7?
I'm not sure I really want to get into being a tube collector. I just want to upgrade to nice tubes that could make the MZ3 even better.

Any advice for me? Thanks in advance

Email LTA, they are very helpful and probably have tried most combinations with their amps. I would assume their OEM tubes are the best they can find that are readily available in production quantities so it would be a good place to start. You do have to describe what you are looking for as far as sound signature. Sylvania JAN 12SN7 chrome dome is my current favorite teamed with Genalex 12AT7 for very clear highs and mids, good tight bass in my MZ3. Some other tubes I have tried are Hytron 12SN7 and RCA 12SX7 which are reasonably priced around $20 per tube and have more punchy bass than the Sylvanias. I just ordered some Mullard and Telefunken 12AT7 to try out which were around $40 a tube + shipping. Try Vacuumtubes.net, they have a wide selection of NOS tubes and are reasonably priced. They test and match tubes at no additional cost and I have never purchased a dud from them.

 

[dpump]

I'm still looking for a pair of the Sylvania 12SN7 Yellow Print Anyone have lead on some?

Let me check my stock. I have many NOS 12SN7 and also RCA 12SX7. I should have the Sylvania yellow print. You can PM me if you are interested.

 

[Killerb]

I am going all in on LTA. My Xmas bonus and a bit of luck got me a used ZOTL40 Reference amp and I paired that up with my MZ3 and Epos M5 speakers temporarily. I can tell you after listening for a few days, this combo makes fantastic noises and the amp should open up the possibilities of driving less efficient speakers as you suggested. My MZ3 came with RCA power tubes which didn't have the sparkle I remember from CANJAM so I dropped in some Sylvania JAN 12SN7 at the suggestion of LTA and they know what they are talking about. The top end is so airy and shimmery that I have been mainlining jazz featuring cymbal work and marimbas (Jack Johnson is also excellent) because the sound is so hypnotic. I am still waiting on the Zu speakers when they come out but I may be perusing my local shop for a home demo with some other speakers to see if one jumps out as a frontrunner.

Regarding the volume...the circuit is supposed to be the same per LTA and I am not an electrical engineer so go figure. My favorite headphones on the MZ3 are the Audeze MM500 as I found the higher impedance HD800S do lack some drive and the Grado GS3000e are not composed enough at both extremes which was especially noticeable after switching the tubes. My old Woo WA2 really brings out the best in the HD800S and Grados which is why I use that combo in my real office.

I am going all in on LTA. My Xmas bonus and a bit of luck got me a used ZOTL40 Reference amp and I paired that up with my MZ3 and Epos M5 speakers temporarily. I can tell you after listening for a few days, this combo makes fantastic noises and the amp should open up the possibilities of driving less efficient speakers as you suggested. My MZ3 came with RCA power tubes which didn't have the sparkle I remember from CANJAM so I dropped in some Sylvania JAN 12SN7 at the suggestion of LTA and they know what they are talking about. The top end is so airy and shimmery that I have been mainlining jazz featuring cymbal work and marimbas (Jack Johnson is also excellent) because the sound is so hypnotic. I am still waiting on the Zu speakers when they come out but I may be perusing my local shop for a home demo with some other speakers to see if one jumps out as a frontrunner.

Regarding the volume...the circuit is supposed to be the same per LTA and I am not an electrical engineer so go figure. My favorite headphones on the MZ3 are the Audeze MM500 as I found the higher impedance HD800S do lack some drive and the Grado GS3000e are not composed enough at both extremes which was especially noticeable after switching the tubes. My old Woo WA2 really brings out the best in the HD800S and Grados which is why I use that combo in my real office.

I was perusing the LTA website last night and they say the MZ3 circuit is not very sensitive to impedance and is affected mostly by sensitivity of headphones which aligns with your experience. Wish it had just a bit more oomph for my HD800s. When I run it as a preamp into my Woo WA6se the staging is excellent and better than the Woo by itself but not as clear and crisp as my MM500 straight from the MZ3.

 

[Killerb]

Email LTA, they are very helpful and probably have tried most combinations with their amps. I would assume their OEM tubes are the best they can find that are readily available in production quantities so it would be a good place to start. You do have to describe what you are looking for as far as sound signature. Sylvania JAN 12SN7 chrome dome is my current favorite teamed with Genalex 12AT7 for very clear highs and mids, good tight bass in my MZ3. Some other tubes I have tried are Hytron 12SN7 and RCA 12SX7 which are reasonably priced around $20 per tube and have more punchy bass than the Sylvanias. I just ordered some Mullard and Telefunken 12AT7 to try out which were around $40 a tube + shipping. Try Vacuumtubes.net, they have a wide selection of NOS tubes and are reasonably priced. They test and match tubes at no additional cost and I have never purchased a dud from them.

I inserted the NOS Mullard military 12AT7 with the Sylvania 12SN7 and the bass is noticeably deeper than the Genelex (can't say it is better just yet) and the top end is still nice and clean. I am going to let it sit this way for a few weeks to see if it sticks.

 

[ThinLizzyDireStraits]

I was perusing the LTA website last night and they say the MZ3 circuit is not very sensitive to impedance and is affected mostly by sensitivity of headphones which aligns with your experience. Wish it had just a bit more oomph for my HD800s. When I run it as a preamp into my Woo WA6se the staging is excellent and better than the Woo by itself but not as clear and crisp as my MM500 straight from the MZ3.

Interesting, just curious, what kind of volume level are you normally at with the MZ3 when driving your HD800s to a comfortable listening level?

 

[ThinLizzyDireStraits]

• That may (will) help out in the soundstage / leanness areas.
• One thought that ‘niggles’ my brain is: what further barriers would be shattered in driving high impedance headphones if LTA MZ3 had a low (2 ohm) / high (100 ohm) output impedance switch (a la Beyerdynamic A2)?
• On another LTA topic, with serial numbers < 200, it’s amazing to think of how few of the MZ3 are out there. Given the time that MZ3 has existed, it really is a testament to the hand-built characteristic of MZ3. Cognescenti!

I just checked mine, my MZ3 #100. I just realized this, but my MZ3 is #100 and so are my Sennheiser hd8xx (#100). Which I use all the time with the MZ3.

It was meant to be.

 

[viggen]

• I like the idea, the parallelism of matching 12SN7 tube pair with 12AT7 tube pair in LTA MZ3. Perhaps “consistency is the hobgoblin of [my] little mind”: 12 volts throughout, no adjustment or conversion.
• There are wonderful specimens of 12SN7: RCA ‘narrow gap plate’, Sylvania ‘yellow print’, and from Japan - Hitachi ‘black plate’ for example.
• AND a 12SN7 tube is substantially lower in price nowadays compared to its direct (same brand / maker) 6SN7 equivalent.
# As for 12AU7 tubes, because of their 20x gain (versus a 60x gain for 12AT7 tubes), they are well suited for preamp and phono preamp use where lower amplification and much lower noise floors are requisite. In LTA MZ3, using 12AU7s might produce a docile sound.

RCA 6189/12AU7WA is very good. Although, in general, 12AU7 is too soft in MZ3.

 

[ThinLizzyDireStraits]

After a month of rolling tubes constantly. I think, i have found MY holy grail set of tube for the MZ3. i have rolled more tubes than the pictures showed. My final 2 pairs are Westinghouse 12sn7 and Emperex 6201 PQ (12at7) gold pin made in Germany. Both sets have halo disk getter.

I have searched and not found many information about these tubes. The Emperex 6201PQ (12at7s ) gold pin beat out well known Mullard 12at7, Tungsram 12at7, RFT12at7 foil disk getter and regular Emperex 6201 PQ(12at7) made in the US.

​

Nice collection. Do you have a go-to site where you purchase tubes from?

 

[VanHai]

Nice collection. Do you have a go-to site where you purchase tubes from?

I purchase tubes mostly from eBay, Etsy (local) and the Forum Classifieds.

 

[ThinLizzyDireStraits]

I have conducted some arbitrary A/B with and without. There is greater focus and detail with Iris in chain. Usual caveats apply (my system, my ears etc.) - YMMV.

I will upgrade Iris to Hermes when I recover from the £700 I was scammed out of for a used Hermes last Friday

What connection are/were you using between the Iris and ARESII? I have the OG ARESII without i2s. So, I wasn't sure if the Iris was worth it, to feed the ARESII since I can't use the Iris i2s output. I assume the ARESII is optimized for the USB input.