12AX7LPS is not a variant of 12AX7; the LPS suffix is a Sovtek code for low noise. So it’s a Sovtek 12AX7 that was presumably tested and selected for low noise. It’s well regarded, at least for having low noise. A randomly chosen NOS 12AX7/ECC83 is unlikely to be as quiet.

Cheers! I've been really happy with mine. What it lacks in load options makes up in fidelity. I just think they nailed it – in my system anyway. Hope it works out for ya.

“A randomly chosen NOS 12AX7/ECC83 is unlikely to be as quiet.”

@lewm

Maybe so but that shouldn’t deter anyone to not experiment, right? It’s a calculated gamble with any NOS tubes…well regarded NOS 12AX7s or ECC83s (like Mullards, Telefunkens, or Amperex) may not be low noise as Sovtek but what they have in spades is harmonic complexity and tonal richness.

The Sovtek 12AX7LPS is indeed not a separate “variant” of the 12AX7 but rather a Sovtek-branded 12AX7 with the “LPS” designation, which stands for long plate spiral. This spiral filament design helps reduce hum in applications like phono stages, where low noise is critical. Its long plates can offer a bit more detail and tonal richness compared to short plate designs.

I had an extensive dialog with the manufacturer prior to my purchase, the Model 4 supports all 12AX7 variants. My particular piece is supplied with JJ ECC803S and it is dead quiet.

Sovtek 12AX7LPS is indeed not a separate “variant” of the 12AX7 but rather a Sovtek-branded 12AX7 with the “LPS” designation,

So for those of us who speak English as a native language, the 12AX7LPS is indeed a variant of 12AX7, whether you subscribe to either Merriam-Webster or Cambridge dictionary. I personally use 12AX7HTF's in my Marantz 7.

Congrats on the Softone. 

@dover ….Correct :-)  

“I just think they nailed it….
@hoytis 

I agree with your assessment. This is a very special phono at a screaming bargain. I have been listening to records two straight days…lol. Have you done any tube rolling? My unit came with JJ ECC803S, they are breaking in nicely and have whet my appetite for more. 

I haven’t heard an amp that hasn’t been improved by rolling in old production Telefunken ECC83/12AX7. Failing that, Grant Fidelity have a Black Treasure 12AX7 that is wonderful.

Dover, who else besides Sovtek make “long plate spiral” 12AX7s and also market those tubes as LPS? But of course you can use any 12AX7/ECC83 in your phono stages.

@noromance

Thank you for your recommendation. And I agree, Telefunken ECC83/12AX7 tubes are legendary for a reason. I am also looking at Mullard’s from 60’s which are known for silky and pleasant top end without being rolled-off. The best of these tubes retain a fine sense of "air" at the top, and the upper midrange is smooth and liquid. These tubes reproduce the human voice, especially female voices, with haunting realism. And then there is Siemens ECC83 NOS 1968, that are favorably touted for phono stages and preamps.

I may end up buying a pair of each and see which one’s are the keepers:-)

TFK ECC83s are so "legendary" for their "tonal richness" that the cost is high, and some duplicitous sellers are selling fakes. Caveat emptor.

I like Telefunkens, but, I never considered them to be tonally rich sounding tubes.  The ones I heard were very lively and dynamic sounding, but, considerably leaner than the likes of Mullard and Amperex.  The Telefunkens that I ended up using in my phono stage are ECC803S tubes that are very expensive.  They came in their original box,  This was quite a while ago when there were some concerns about fakes, but, the Chinese had not yet perfected the fake diamond molded into the bottom of the tube.  The box looked suspiciously clean and new, but the ends crumbled when I opened them, which indicated that t boxes were very old.  

For warmer sound, I like Amerex Bugle Boy 12AX7s.  

Haven't rolled tubes yet. Haven't felt the need yet. But never say never.

Link to my aforementioned Black Treasures.

TFK ECC83s are so "legendary" for their "tonal richness" 

No they are not.

Exact opposite - in the Marantz 7 circuit they are fast, reasonably transparent and very flat. I have a draw full of premium flat plate Telefunkins. They have never sounded rich.

If you want rich - Mullards tend to be much more fullsome the expense of speed and neutrality.

The problem with any discussion on tubes is that the best tube can be circuit related - you can't make blanket statements.

I like Telefunkens, but, I never considered them to be tonally rich sounding tubes.  The ones I heard were very lively and dynamic sounding, but, considerably leaner than the likes of Mullard and Amperex.  

Absolutely correct - I have drawer fulls of flat plate telefunkens - they are as described. I also have a stash of Mullard CV4004 and M8137's both are richer and fuller sounding than the Tele's.

In my Marantz 7 I preferred the Telfunkens.

In my Jadis preamp I preferred the Mullards in some positions ( but not all ).

@dover Funny, I had a drawer full of the box plate Mullards you mention. Nice if one likes creamy, warm, and slow, with no air. I'll concede that Teles can be a little lacking in warmth. However, I maintain that you can adjust tonality elsewhere in the system without slowing it all down in the phono amplifier.

@dover, @larryi 

You both are right—Telefunken ECC83s are not “tonally rich” in the sense that Mullards or Amperex tubes are. They’re prized for their neutrality, speed, and precision rather than warmth or fullness. Their sonic signature tends to be leaner, more transparent, and dynamic, which is why they excel in circuits like the Marantz 7, where their neutrality complements the design’s inherent qualities.

As you mentioned, tube performance is highly circuit-dependent. Telefunkens might shine in a circuit designed for clarity and speed, while Mullards or Amperex tubes with their fuller and richer sound, might be better suited for systems aiming for warmth and body. It’s fascinating how tube rolling allows for such fine-tuning, but also how generalized statements about “the best tube” fall short when we take into account circuit topology, system synergy and personal preference.

Your experience highlights the beauty of experimentation, something I deeply believe in.

Do you find that your preference for Telefunken or Mullard shifts depending on the type of music you’re listening to or is it the system’s overall tonal balance?

Dover, Please lighten up. I was quoting Lalitk. That is why the words were in quotation marks.  Evidently Lalitk experiences the TFK ECC83 as tonally rich. As we all know, one's impressions of the SQ of any single item in a system are dependent upon what else is in the system and what is in the caput of the listener. Although I have to say that I preferred the sound of TFK ECC83s against any other congener in my Quicksilver preamplifier, I also hold with noromance that you can adjust tonality elsewhere, such as by careful choice of output coupling capacitor, and etc. I used the TFKs in the Q because I have owned a quad of them since the 1970s, and I figured I ought to at least give them a try.  The Quicksilver is a superb sounding unit, in my opinion, but these days it just sits on the shelf.  Mullards were underwhelming in the Quicksilver, not even second choice. I am in general not a fan of tube rolling at all.

Do you find that your preference for Telefunken or Mullard shifts depending on the type of music you’re listening to or is it the system’s overall tonal balance?

No. I listen to mostly Jazz & Classical.

My preferences are for maximum speed and transparency. I very seldom have any issues with system balance - having multiple arms/cartridges is enough.

One thing I cannot stand is slowness or aberrations/colourations - I find that ultimately they grate on you over time. Best to build a balanced system to start with.

In terms of tube choice - its the particular application that can determine tube variant in my experiences - specifically with classic circuits eg Marantz you have tubes that perform gain functions and tubes that are used in a cathode follower application ( no gain, used as buffer to generate a low impedance output ).

Occasionally I have found that the 2 best tubes in those positions are not the same.

@lewm

I used to distribute Quicksilver, I have owned them years ago - the QS preamp runs the tubes very very hard. 

@dover

Your focus on speed and transparency aligns perfectly with your preference for a balanced and revealing system. It’s great that your approach to tube selection considers the nuances of classic circuit design. That level of detail ensures optimal synergy and performance without introducing unwanted coloration or sluggishness.

My journey into analog so far has been nothing short of amazing experiences. There is still lot more work ahead as I look forward to receiving the elusive Woodsong plinth + implementation of 2nd tonearm and Mono cart by Spring 2025.

Dover, I own the old QS preamp that has a built in MM phono stage, along with its linestage, not the newer models that I think are separates, a phono stage and a separate linestage.  Since I have measured the voltages across the tubes, and thereby also calculated plate current and plate dissipation, I can assure you that the early 1990s era QS does not run the tubes "very hard". The plate dissipation is well within spec. Upgrading the capacitors in the RIAA filter and the output coupling capacitors does wonders for the sound.

@lewm 

Dover, I own the old QS preamp that has a built in MM phono stage, along with its linestage, 

Yes - that's the one I'm talking about. In hindsight it may have been the power supply feeds to the tubes that had some design foibles that were precarious. I have the circuit diagrams here with updates by Mike ( there were several updates to that pre ), but my tech was not happy. He did explain to me the design issue, but I can't remember the detail - its some years ago.

Its an ok preamp.

@lewm If you find that:

Upgrading the capacitors in the RIAA filter and the output coupling capacitors does wonders for the sound.

I am surprised that:

I am in general not a fan of tube rolling at all.

It seems to me that if a better capacitor does wonders, then a better tube might as well! Perhaps I have fooled myself, but I'm surprised to find that changing a rectifier tube can affect the sound quality, never mind the tubes in the signal path. I am not guilty of changing types of tubes, only the manufacturer.

I bought a used Softone Model 4 last week. It easily bests my GoldNote PH-10 with PS-10 LPS.

I’ve rolled NOS Mullard, Telefunken Diamond Mark, RCA 6201, and GE, as well as some Gold Lion reissues that came with it.

I prefer the tele’s in the phono stage by far, but much prefer the RCA and Mullard’s in my DAC.

Unfortunately the Model 4 has a noisy left channel, so I’ll probably order a new one from Japan, then send the used one back for repair and hope the repair is reasonable - then sell it to recoup a few bucks (hopefully).

@lalitk thanks for letting me know about the Model 4!

@macg19 

You’re welcome! Sorry to hear about the issue with left channel, hopefully you can get it repair easily. I really appreciate your feedback on tube rolling, I am still using stock JJ’s …the phono is now fully “broken-in” and I’m really enjoying its warm, organic tonal characteristics. IMHO, this little giant slayer is a perfect fit for systems that are tuned or end user’s prefer intimacy and warmth. 

Inspired by your feedback, I am going to swap out JJ’s with NOS Telefunken 12AX7 this weekend. What cart you’re using with Model 4? 

Cool, let us know what you think of the Tele’s.

my cart is MSL Signature Platinum, TT is Clearaudio Innovation with Universal arm

Ive order a pair of the Sovtek LPS so I can compare with the stock set up

I made that suggestion months ago! 

noromance
12-04-2024 at 12:16am 
I haven’t heard an amp that hasn’t been improved by rolling in old production Telefunken ECC83/12AX7.

@noromance 

Indeed you did and I ordered the NOS Telefunken based on your initial suggestion but then I completely forgot about them….lol! 

@macg19 post reminded me that I had NOS Telefunken’s sitting in my closet.

@lalitk Great. Give them a few days to settle in before judging. 

@noromance, @macg19 

I have been listening to Telefunken NOS 12AX7 since yesterday after 4 days of break-in. Let me first say JJ 12AX7 are excellent tubes for the money. My biggest concern was noise with Tele NOS. Fortunately, they turned out to be dead quiet. 

Now the differences, JJ pair in contrast were slightly darker and bit forward in mid-range. Tele NOS definitely has more refined mids, slightly sweet and smoother top end. If I may say so, excellent layering and microdynamics too and very  emotionally engaging. 

They are allowing me to fully appreciate Ben Webster’s velvety and breathy tenor saxophone fully bodied sound at another level. I own several recordings of Ben’s music and every one of them giving me goosebumps :-) 

I can’t praise enough my Model 4 phono…what an amazing bargain! I may order another one for my 2nd tonearm. 

Thank again! 

@noromance Lalit - funny, I was literally just wondering how you were getting along with the tele's. Also Ben Webster was one of my go-to's for testing the Softone.

Glad you like the tele's.

I had a chance to warm up and test the Sovtek LPS variant and tried it in the Model 4 and my tube DAC and it is surprisingly good. I think I like it best in the DAC, but at $60 a pair these are the best new issue tubes I've heard so far and easily best the Gold Lion reissue's that were included by the seller with the model 4.

btw, I ordered a new Model 4 from Mr. Yoshimoto - it will ship early next month, then I'll get the used one repaired (if cost is reasonable) and put it up for sale.

Lastly, I did some more a/b testing between the Model 4 and my Gold Note PH-10 with PSU-10 (3 x the price), and it's not even close. My "busted" Model 4 really is remarkable - can't wait to hear what a properly functioning one sounds like!

@macg19 

I had a feeling Tele NOS would be better since I am using quad of Tele NOS in my CD player. Speaking of tube rolling, I always wanted to try Amperex Bugle Boy 12AX7 but they are so rare and expensive. 

The reissues or newer tubes are pretty good but they simply cannot match the vintage NOS tubes distinctive characteristics adding subtle but meaningful improvements in tone, texture, and timing. Gotta go, just received a fresh delivery of Ben’s new albums from Amazon :-) 

Enjoy! 

@macg19 

In case you don’t own this title, very nice and clean record. 

https://a.co/d/daCwZyd

I dont, but randomly, it was the first album I streamed today after you mentioned Ben - I’ve never listened to it before. Very nice indeed.

Listening to Kenny Burrell Midnight Blue atm.

@lalitk  Good to hear and thanks for following up. How is the vinyl and remaster quality of the Ben Webster Plays Ballads album. I've a damaged original and forgot about replacing, and frankly was hesitant to get the new RM for fear of it being damaged by the digital process!

@noromance 

Ben plays Ballads by Storyville is excellent. No surface noise, the pressing is made in EU. I am not easily impressed but this one is a keeper. I am going to look up this record label and see what else they’ve got. 
 

@macg19 

Kenny Burrell Midnight Blue atm.👍

Cheers @lalitk 
I only have a Muggsy Spanier album on that label.

@noromance 

I didn’t find anything else on Storyville Label that I couldn’t live without :-)

As I mentioned above, I run genuine, old, Telefunken ECC803S tubes in my phono stage.  These take the Telefunken clarity and dynamics even further out to the extremes than the ECC83 tubes.  I like them in my system, but I don’t think they have universal appeal.

If I were to pick a tube as being universally good and likable by everyone, it would be a Bugleboy.  These are on the warm side, but, they have good clarity and are lively sounding.  I don’t know of anyone who hates their sound.

@larryi  As you know, you could buy ECC803S for £6.95 each back in the 80s. Now they’re over $1000 each NOS.

Limited, and not growing supply (Chinese fakes don’t count), and high demand did  that to the price.  I’ve had mine for many years and they are still going strong.

@larryi 

@noromance 

There are bargain out there if you’re patient. I got my last pair of Telefunken 12AX7 NOS ( Made in W Germany) for under $100. Setup alerts on HiFi Shark and take your pick. 

I am not in the hunt for any tube.  I already have my preferred tube and I expect it to outlast me.  My only significant concern is with securing enough output tubes in my amp to last to the end.  I run four 349 output tubes.  Those are very rare and expensive.  The other extremely rare tube I run are 348s and I have spares and the really cheap 6F7 can be used as a substitute so I don't have to worry about that tube type.  Slightly more findable are the 310a and 310b that I run.  

@larryi 

Noted. 
 

@noromance 

Side by Side (Acoustic Sounds Reissue)

I am really enjoying this classic duo album where Hodges steps out front with Ellington’s graceful support. Swinging, relaxed, and full of lyrical alto work.

@lalitk  Note that we were talking about the Tele ECC803S which is never under $700 (used). It's a premium ECC83. 

Yeah, Side by Side is solid. 

I guess I have written this many times, but for me the TFK ECC803S must be so rare by now that I would demand quite a bit of documentation before spending so much money.  Even a TFK ECC83 is in the realm of caveat emptor.  I bought my quartet of TFKs in the early 70s, and they have been in my possession ever since, so I feel confident that they are what they say they are. I don’t feel that I am knowledgeable enough to identify by physical characteristics, except for that diamond shape etched into the bottom of each TFK.  Anyway, some modern 12AX7 reissues are good enough, in my opinion, that I would not worry about the brand too much. I have heard the Sovtek LPS and the JJ gold pin sound excellent. OTOH, I don’t think much of the Mullard, even assuming that the Mullards I own or have heard are the real deal.

“Tele ECC803S which is never under $700”
@noromance 

They cost twice as much as my phono stage….yikes!! 

Ben Webster is a personal fave - I have 28 of his lps!  Three go tos not mentioned yet include Ben Meets Oscar Peterson, Ben Meets Gerry Mulligan, and Coleman Hawkins Encounters Ben (track 2, side 1 is beyond brilliant).

“Ben Meets Oscar Peterson, Ben Meets Gerry Mulligan, and Coleman Hawkins Encounters”

@mdalton 

These albums are must own in any collection and they’re my favorites too. I would like to add another one to the list  - 

Art Tatum; Ben Webster

The Tatum Group Masterpieces

28 LP’s…wow! 

I also love Ben’s work on Gentle Ben and Stardust albums.