27 August, 2009

Extended Audition: Lowther Diary (SE amps)

Extended Audition: Lowther Diary (SE amps)

Lowther diary 2: more amps, including 801A
(Edited from the article that started the thread here, on 17/3/2001)

"..To pick up where I left off last time.

I had been listening happily to the Foreplay preamp + Wai Lee amp with cheap E130L tubes. But one of them intermittently emitted a noise. I substituted the San Ei 6BM8 kit but one channel is noisy too (from long term disuse), so I went back to the Wai Lee. My ICL 2A3 is on

Yesterday Thomas, David, and Richard C came over to listen to the Lowther TP1. The E130L was acting up so I put in a pair of (late) KT66. Sound was a bit smoother than the E130L, and good enough to me. Large orchestrals tightened up though at higher volume. We listened to a bunch of stuff before Thomas asked to put in the San Ei 801A amp.

A bit of explanation. I seriously believe the transmitting tube 801A is an excellent DIY tube (brand new Sylvania ~USD 40). It uses >600V voltages and puts out 3.5 watts. But it needs a 10k output, a problem. Mine is an old San Ei kit (now closed) with all Tango trans (Tango is
gone too), bought form all people my neighbor!!! It uses 12AX7 and 12BH7 also. ss rectification.

I used a 6mV DAC direct into the amp, and used the amp's volume knob. To my surprise, the sound, though even smoother than the Wai Lee, lacked some dimensionality and orchestrals lost speed. Someone said this combo sounded more like conventional speakers. One thing good
though; large scale sound gained some composure. Put the preamp back in and things came alive, though the dimensional qualities were still behind the Wai Lee. Finally we hooked up the amp to La Scala, and it was that much more lively.

The performance of the 801A was a little surprising to me. It works perfectly with the La Scala, and makes me want to sell many of my other amps as it is enough for me. With the La Scala I only need to run the CD directly in. But this is not the case with the Lowther.

Some thoughts again:

-Again this demonstrated that Lowther is NOT as efficient as La Scala (9x db vs 104 db on paper). You need more driving power, and preamp, to make the Lowther come live.

-The horn aspect of the sound quality is less pronounced and requires care not to lose it. With the La Scala you do not have this problem. Anything goes happy and its always horny.

-Aside from the location problem (mine are not in corners right now, they are in middle of room), careful titration between speed and power may be needed to maintain horn quality, yet make music loosen up at higher volume and complexity"...

Lowther Diary 3: 300B
(Edited from an article that started the thread here, on 20/03/01)

For the last few days I hooked up my Advance 300B amp to the Lowther. This is a 6AN8 driven amp. ss rectification. Japanese kit, acquired thanks to Eric. It is not the most powerful 300B but has a warm sound, perhaps due to its being driven by a pentode section and with

I first used the Valve Art 300B and cheap Monster cables. Sound was more relaxed than the other amps used before, but it was a bit polite. Strange. I didn't realize the VA 300B were so polite before?

I changed to Svetlana and the Radio Shack cables and the sound balanced out by quite a bit. Actually this combo really loosened up the speakers by de-emphasizing the lower treble, and yet keep the treble afloat. I played even a Bruckner symphony last night.

The sound seems to continue to loosen up. Good. TKL asked me why am I posting this Lowther diary. Because I believe this experience can be shared with any Lowther user, even the
cheapest. One point I want to do is to have SOME detail in why I think this is this and that is that. Not just to say x is the best and y is the worst. I'd welcome any user to detail their experience in tube SYSTEM.

The matching of different amps to Lowther is a completely different experience from La Scala. It is just that much fuzzier. ALSO, cables prove to be a HUGH difference, as much as tubes, may be more. One can play many ways. Many HK people will probably just change all kinds of
tubes in 1 amp to see whether they can "transform" the system. I have never thought this productive. Better to see the system as a whole.

I have read a lot of threads on the Yahoo Lowther group (and has joined as member). It's interesting how many different types of amps have been used for Lowther. But few people do have several amps to compare at any given time. After I play some more I'm going to combine
the threads and post it in the Lowther forum. There are some HK people, including one person using M9 (switched to Klangfilm)to drive it!!!!"...

Lowther Diary 4: Humidity, new position, more 300B, Wai Lee re-visit
(From an article that originated the thread here, on 26/03/01)

"The Lowther sounds better these days to my ears. No doubt not at all solely due to my manouvers. I believe it's the humidity (alledged by many to be true). Seriously.

Well, uncontrollable factors aside, there have been important developements.

After the Advance 300B experience I got back my Audio Note kit one, in which I put my Valve Arts. No question, better line and speed and definition compared to the Advance. But a bit impersonal heh? Never noticed that before with the joyful La Scala...perhaps it's the Lowther?

Saturday, Hoi came over and with GREAT patience helped me move things around. As some of you know, I have so many things around that moving ANYTHING is like playing with Rubik's cube. We dismantled my 2 hifi racks, and moved a large rack (holding gears and CDs) to the opposite wall. This allowed the Lowthers to be more WIDELY spaced, now about
10 ft apart (7-8 ft from me), and they each gained ONE solid reflecting surface. The sound was immediately more easeful. I know these are still not ideal, but they will do for the moment. Next time I get help I am poised to exchange position of these with my far corner La Scala's. Tantalizing...

The effect of re-positioning:

-More easeful. Things just flow more naturally. The quickness of the notes do not become mechanical. Much better for large scale music.

-Due to the distance between the 2 speakers (relative to the distance from me) no doubt the imaging is less sharp than previously. This is less of a concern for horn users, but noticeable nonetheless, particularly on small scaled pieces. Amazingly even the bass outline loses slightly sharpness. In larger works, the ambience gained outweighs the slight loss in focus. There is little doubt these speakers prefer larger rooms.

With the new positioning, the amps sound very different, and more play is needed."...


  1. Dr. John,

    what would consider for amps and source for a Lowther based speaker (Rethm Saadhana with integral driven bass)? I'm using a First Watt F3 and passive preamp and a Red Wine Audio Signature 15 integrated sourced by a Denon dvd player with Metrum Octave or Eastern Electric dac. The sound is either over-detailed and etched or too bland. My cables are Cardas Golden reference.

    Thanks for your consideration,

  2. Hi Greg,

    Your choice of equipment is unusual to say the least. I'd have loved to hear the Rethm. I have only seen them silent! :-)

    If it is over-detailed and etched, then a bit of tube will benefit greatly. Lowther-like drivers love tubes in general.

    If it is too bland, and you need more jump factor, a passive preamp is a definite no-no. I personally do not like passive preamps in general, even most TVC's.

    Given your solid state amps I'd think a well chosen tube preamp will solve both of your problems. It provides more jump factor than a passive preamp and acts as a buffer too to ameliorate nasties. See if you can borrow one to try. Or maybe build one, something like an AN kit or Bottlehead?

    Of course, I'd prefer to use SET amps rather than FETs to drive the Rethm. But maybe that is moving too fast! :-)

  3. Greg, I forgot to mention too that the tube stage in the Red Wine is likely just a buffer, and the volume control is likely just a passive stage. Turn the Red Wine volume to approximately 12 o'clock, add a preamp and slowly turn up the volume of the Red Wine. If there is no distortion with the volume turned all the way up, it is a passive stage.

  4. Dr. John,

    thanks for your quick response. I have considered getting a Bottlehead DHT preamp in the past, amongst others like Manley, Coincident etc. Mingda makes a 2A3 and 300B that are about the same price as the Bottlehead if you had someone build it. I'm considering just starting fresh and selling off stuff. Maybe the Wavac MD300B or the MD811, purchased used, to be cost effective and no need for a preamp. Any other suggestions would be greatly appreciated.
    Awesome blogsite btw.

    Thanks again,

  5. Hi Greg, take your time, there are so many options. Seriously consider taking up soldering! It will provide you with more fun later, like making your own cables (Gotham and Mogami e.g., and then you can sell the Cardas for good money). There are many good SET amps, Wavac is certainly great. In terms of C/P ratio, the Wavac 811 is wonderful, sometimes you see them really cheap. Ultimately I'd think a tube preamp is also good.

    Buy something that has resale value, like Wavac, Sun Audio etc. Audio Note Kit One is also excellent. Take your time.

    Somehow my favorites are kits. Elekit is another one. vkung sells them and can have them built for you.