Preamp shootout: Linear tube audio, Modwright, etc.


Hi Audio friends,

The world of preamps is taking me down a lot of rabbit holes and I'm curious what everyone out there thinks.  My journey here started with using my Dac direct to amp.  As soon as I inserted a dedicated pre the debate over pre vs. no pre ended.  Didn't realize I was missing a third of the music.  My current rig: wilson sabrina's, Coda TS v2 power amp, exasound DAC, silnote & cardas cables .  I was using a Modwright LS100 and I'm currently trialing the Linear tube audio ref pre.  The LS 100 is holographic, images well, but is not nearly as open or detailed as the LTA.  The LTA is gorgeous through the mids, but is a little muddy through the bass and not really suited for hard rock.  Wonder if different tubes would make a substantial difference to the LTA?  If anyone has experience please share. 

What other options might be considered in this price range?

 

cshadow

I’m interested in this ... I have had an interest in the LTA preamps for some time. There are some reviews out there which rave about them (the MZ3 and the full preamp). I have never owned tubes, and am mildly obsessed with the idea!

Primaluna Evo 400, Backert Labs Rhumba 1.3, Rogue RP7 for tubes. Any Ayre preamp for solid state. Those are ones I've tried in that price range.  The Primaluna was the most "open" of them all. Depending on what I'm listening to, what time of day/night and my mood, I could live with any of them. I see you considered the Ayre K-5xeMP in the past. For $2k it's tough to beat.

I went from a LS100 to a Herron VTSP-360. Kept the holographic presentation, gained more clarity into the music.  Contact Keith directly for the best price. 

The LTA is a really beautiful piece of kit.  Easily the quietest tubed pre I have ever heard and the low volume resolution is exceptional.  The LS100 is not as clean sounding or anywhere near as resolving, however EVERYTHING sounds B+, or even A-.  The LTA has a lot more A+, goosebump moments, but when it doesn't sound good it really doesn't sound good.  . Compared to the prima luna, the LTA is simply in a different class.   Curious about the higher end Ayre gear or ARC, but, as always, cost is the issue.  Thanks for the Herron suggestion BigG!  Your recommendation re tubes def made the modwright better btw.

I am currently testing 3 preamps. I have the coda 07x preamp which is the best SS pre I’ve ever owned. The Vinnie Rossi LIO DHT and the Direct Heated Triode stage sound gorgeous. I also have an LTA MicroZOTL Preamp. All three have their strengths and few weaknesses but the LTA MZ pre at this point is my favorite. I get blow back for liking the LTA over the Vinnie Rossi but this is just my opinion. Yes the MZ pre is extremely quiet or completely noise free. It’s almost as holographic as the LIO DHT but it’s much faster and dynamic. The MZ pre is sensitive to tube rolling so have at it. The MZ pre allows me to enjoy rock and jazz with nothing lacking but if you really just want to rock there’s nothing like solid state. I am a fan of Modwright but have never owned their preamp.

Went from the LS 100 to the Herron 3a—not even close. The LS 100 was noisy, soft, and not nearly as dynamic. Now own the 360 Reference which is better still.

@lancelock Interesting to hear your perspective on the coda pre.  Doug at Coda is one of my favorite people in the audio world and I have no doubt that his pre is fantastic!  This coda TS is a powerhouse.  I think you have helped me make my decision.  There is something special about the LTA and your are right in your assessment of the speed and dynamics.  

There is a constellation pre for sale right now that is intriguing, but this is a forever hobby and for better or worse one has to stop and enjoy the music at some point.

@cshadow

I think a lot of us tried the DAC to amp experiment so do not feel alone. I used to discount the importance of the preamp and thought it was a place to save money. My current preamp costs as much if not a little more than my amplifier so yes, I clearly changed directions on this topic. My .02 is to put all you can into your pre and punch a little above your weight if possible. Cheers.

@phcollie  - Yeah - I hear you.  Went from loving integrateds, to thinking I was somehow ahead of the curve going Dac to power amp - LOL

Have a whole new respect for the Pre as a result.  It really is the heart of a good system.

@cshadow 

The MicroZOTL Preamp is superior sounding to the MZ3 and is a wonderful match with my Coda No 16 amp.

Zesto Leto is a great preamp....  zero noise.   Black background,  dynamic , perfectly voiced in my opinion.   Lots of inputs and outputs.  

With LTA, the 12sn7 isn’t the dominant circuit tube so stick with their stock ones which are quite good. However, definitely need to switch the small tubes for optimal performance. Removes glare.

Backert Labs is on my list, along with a few of the ones mentioned. Has anyone compared them?

I compared the Backert to a Rogue RH-5 (which is supposedly better than the RP-5 and rivals the RP-7), and preferred the Backert, though the difference was very far from night and day.  The Backert is also, for ease, a tube-rolling champ.

I am leaning toward the Modwright 36.5 DM. It is on next years wish list. Lots of time to do the research on the options. Thank you, 2LE.

If we had the,money as some of you guys do in here, would get a full McCormack monoblock pair 600@8ohm, the vre-1c preamp, Rotel 1572 CD player, 

and 2 bottles of Bushmills 21year single malt Irish whisky!

There’s a tube rolling thread about the MZ3, which was the same circuitry as the pre until the latest update, but I didn’t see anything specifically about bass issues.

Another contender for you might be the Aric Audio Motherlode II. Review

"I think a lot of us tried the DAC to amp experiment so do not feel alone. I used to discount the importance of the preamp and thought it was a place to save money. My current preamp costs as much if not a little more than my amplifier so yes, I clearly changed directions on this topic. My .02 is to put all you can into your pre and punch a little above your weight if possible. Cheers."

+1 @phcollie. There's no better teacher than experience.

Charles

cshadow OP
19 posts

If you want to wander off the beaten path slightly, I suggest you take a look at the LKV Research Line One pre-amp.  It is a solid state differential balanced preamp, no remote, separate power supply, and to my ears better than the LTA microZOTL preamp (which I use to own) for detail, sound staging, and overall musical presentation.  It will not win any beauty contest, but it is worthwhile considering.

Are you testing the original or upgraded (level 2) LTA preamp?  I just got my LTA preamp returned with the upgrade today and the bass is a bit deeper/tighter. Still evaluating other aspects of the upgrade - definitely a bit better overall.  I would agree with those who posted above about rolling the small tubes - since the LTA doesn't drive the tubes hard, it makes it easier to upgrade without worrying about burning through expensive tubes.  I put in some NOS Siemens 12AU7s and the sound definitely was a little clearer and cleaner over the stock tubes.

@giantsalami I love my. Modwright 36.5.  Upgrading the rectifiier tube, as recommended by Modwright, makes all the difference.  Ask Vintage Tube Services for a god Mullard. The 6h30's don't make that much differennce 

The two I can think of that could be interesting are:

PS Audio BHK Signature

AVM Evolution PA5.2

In both cases the stock tubes are not optimal.  In the case of the BHK, there is a pair of NOS Tunsgrams that really brings the unit to life and it is a VERY good sounding preamp.  I used it for about a year with a variety of amps and was quite happy.  I scrapped it because PS Audio went direct and I did get a better preamp from Art Audio.  

The AVM uses ECC83s.  I recommend rolling in NOS Mazda Cifte's if you want detail, Mullards if you want sweetness.  This unit is feature packed including tone controls, input attenuation, etc....  I have this unit here now as one of my preamp demos.  

 

I really enjoy my BHK, however, I'm not certain if it is a TRUE tube preamp....its a hybrid. 

The PS Audio BHK is really good, but I found it responds well to tube rolling - you really need to roll the tubes to get the most out of it. Since it does respond to tube rolling, I would call it a good tube preamp.  I do like that it is a bit of a swiss army knife of a preamp since it has a large number of balanced and unbalanced inputs. 

Overall, I'd say with stock tubes it performs below the LTA original generation; with better tubes about equal to the LTA OG.  The LTA with the level 2 upgrade I would place above the PS Audio.  Of course, if your equipment performs better using balanced gear, the LTA might not win in a head-to-head.  

The LTA preamp is definitely in the upper echelon. I believe that a fully balanced option will be available next year possibly. Regardless, the MZ Pre level 2 is a keeper for me.

I’ve had an MZ2 for about 3 weeks and it’s definitely the best preamp I’ve heard in my system.  Quiet and uncolored. 

+1 for Modwright 36.5

It is the one of best Pre amplifiers on the market. I am just wondering there are so few talking about this pre.

 

 

I owned ModWright LS36.5 single chassis version for many years, at the same time I also own Einstein & Aesthetix Janus Signature.  LS36.5 had upgraded rectifier.

LS36.5 had stellar bass control, not the most weight, but deep and taut, much like BAT VK51SE which I used to own.  Midrange was quite neutral, borderline flat or boring sounding, again like BAT here.  But top end is why I sold the pre.  It's a bit recess, lacking air and extension and this is playing back on Aerial 20T with excellent air, with that comes with missing details.  I did play with 6H30DR to ill effect, at the end decided to let it go.  I sold my BAT51SE for the same reason, but I have many BAT amps in my system which is a completely different animal.

Another reason for staying away ModWright was their service, Dan certainly left a pretty bad taste in my mouth...

In comparison, Aesthetix Signature is much more open, more apparent to tube rolling, and more flexible, though it does have higher noise floor.  Nothing came close to Einstein so far.

Very happy with my LS36.5 and I’ve compared to ARC units around the same price and a little more and I’ll keep my ModWright. Using the Mullard rectifier with Herbie tube dampers on cryoed 6H30’s. Per Dans recommendations I’m using mostly WyWires cables and highly recommended the Daedalus DiD’s, which really opened up the LS36.5. Every time I have spoken or emailed Dan, he has always been courteous and easy to work with and has giving me great deals. 

Hi,

verdantaudio

Anybody know

 

What are the improvements that can be made in the excellent AVM Evolution PA 5.2

 

Thanks

 

.

Anybody else running the AVM PA 5.2 that can comment on it as well as any other tube recommendations? Comparisons to other preamps are most welcome as there are not many places to demo anything nearby to me. 

Sorry I missed this guys.  The stock tubes from AVM are good sounding and extremely quiet but are not great in terms of detail and imaging. 
 

Staging is enhanced with good NOS tubes in every direction.  I find depth is most enhanced by Mazdas.  Mazdas are also quite detailed and tonally relatively neutral and flat from a frequency response perspective.

 

Mullards are slightly rolled off in the treble.  Big staging in every direction and strong levels of detail with a richer midrange.  
 

I have not tried other options.  I have since sold my PA5.2 and those are the only tubes I rolled in.  You could reach out to Tube Depot or Brent Jesse to see what they have to say about their options for ECC83s.