DHT OTL Linestage - Tram 2

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Hi Brian
I have some 2a3’s and 45s, but I'd like to run this with the 01-A. Thoriated tungsten filaments, more gain, etc.
The filaments need 5 V. 0.5 A, and B+ is 135.

And the 71A: same filament supply; max B+ is 180, but 135 should be ok

How much would you charge on top of an assembled amp, to set it up for them?
 
Tram 2 ,best i ever had

Like to tell a little about my Tram 2 pre---the sound is the best i have had in my system---it had the feeling that you are in the music--this i have not heard before---the review by enjoy music is just right--so i am very happy by the result---
i have make some hum and microfonic damper-----2 big iron tube--one over each 45 tube--
and a wire from the iron to shield on the input---this had removed all hum--and less crackling on start---les microfonic--
the iron tube is 10cm Ø---15cm high---5mm thick--
if someone like it---i can tell about what i have compared,the Tram 2 with--
thanks to Diyhifi-supply for good service---(Simon)

sorry my bad english--
Bjarne
from Denmark
 
Like to tell a little about my Tram 2 pre---the sound is the best i have had in my system---it had the feeling that you are in the music--this i have not heard before---the review by enjoy music is just right--so i am very happy by the result---
i have make some hum and microfonic damper-----2 big iron tube--one over each 45 tube--
and a wire from the iron to shield on the input---this had removed all hum--and less crackling on start---les microfonic--
the iron tube is 10cm Ø---15cm high---5mm thick--
if someone like it---i can tell about what i have compared,the Tram 2 with--
thanks to Diyhifi-supply for good service---(Simon)

sorry my bad english--
Bjarne
from Denmark
Sounds like a good solution as the 45s don't get particularly hot. The Tram mkII does sound really great doesn't it! :)
 
"The diyhifisupply site has details and link to the review of the mkII"

Yes, I've read all that

"original Tram WOT but I do know that WOT means "With Output Transformer", the mkII does not have an OPT. The mkII is a totally new preamp, sharing nothing with the WOT"

So they are both relatively unique in being WOT. How do you know it is *totally new?
 
"The diyhifisupply site has details and link to the review of the mkII"

Yes, I've read all that

"original Tram WOT but I do know that WOT means "With Output Transformer", the mkII does not have an OPT. The mkII is a totally new preamp, sharing nothing with the WOT"

So they are both relatively unique in being WOT. How do you know it is *totally new?
They are not both WOT. The mkI has OPTs, the mkII does not. The mkI used 5687 whereas the mkII uses 2A3 / 45, it uses the DIYHS heater modules, Active Bias module, Ultimate Volume Control Module, Universal all Film Capacitor Power Supply.....I don't believe these modules existed when the mkI was around. Like I said, totally new.
 
Hej Carlo
i dont now how to upload picture---i could perhaps send it on mail to you---
the iron tube is just a water tube - i have drilled some holes in---for cooling--
the reason why i have make that---is-- that the tram 2 make hum---worse when i hold my hand over it--the iron tube removed it totally--but remember the wire to input ground
i am not finished with the iron tube---have to paint it black--

Bjarne
 
I have my Tram II up & running now and it is completely amazing.

I am using Valve Art 2A3s which are, well, very good, and quiet.

We should really get a tube-rolling discussion for this pre going. I too am interested in how 45s would change the sound. I only have mesh globe 45s which are not really suitable.
 
I have 1 pair TJ45 mesh, 2 pairs of old 45s, 1 pair RCA Cunningham 2A3 (NOS).

I need have a more current rolling session but my observations so far are the TJ45 didn't have the fuller body of the old production tubes, but this was before I'd fully damped the tubes. It seems like any new production tube is more microphonic than most old production ones, this shows up as brightness. The old stock tubes barely need damping rings (Herbies).

It's hard to compare the tubes in meaningful way. The 2 big variables are:
1) effects of microphonics
2) the age and use of the tubes in question

My RCA 2A3s are the best sounding (detail, harmonics, richness).....they are NOS so not microphonic and have very few hours use. Next come the old stock 45s, very heavily used but still sounding great. The TJ45 are good but in my setup I can't really get them far enough away from the speakers. I will try to run a more recent comparison but it will take me a few days as I'm travelling.
 
I have my Tram II up & running now and it is completely amazing.

I am using Valve Art 2A3s which are, well, very good, and quiet.

We should really get a tube-rolling discussion for this pre going. I too am interested in how 45s would change the sound. I only have mesh globe 45s which are not really suitable.

Paul, can you share your experience and the other preamps you've compared with the Tram?

Thanks!!
 
Clive, FYI, I found your review spot-on. I followed your advice re the Herbie's dampers which I'm sure is a contributor to the stunning sound I'm getting out of the Tram. (I just listened to it for the first time last night.) Here's what I wrote to Brian:

"This thing is absolutely amazing. I do not say that lightly - not in the least. I expected it to be utterly transparent and very dynamic but I was "worried" (more like curious) about two things: would the noise level be decent enough and would it be musical? The Enjoy The Music reviewer was able to conquer noise & microphonics problems but my speakers are also very efficient and much closer to my equipment than his. As for musicality, that sometimes seems mutually exclusive with transparency - although, of course, some gear pull both off marvelously.

In my experience the most "musical" line stages around are Shindo, and they are very transparent as well (although almost certainly colored to an extent). The Monbrison I had was probably my favorite piece of gear of all time.

Well, here's the verdict: Not only is the Tram II the most transparent and dynamic line stage I think I have ever experienced, it is also dead quiet, has no issues with microphonics, and is incredibly musical. In this case, it seems that transparency does translate directly to musicality!

It's simply incredible. I've been using a <<very good tubed line stage - snipped>>, and this preamp absolutely smokes it in every single category. Major veils have been lifted - my system now sounds like I was listening through fog previously. Dynamics have gone up several notches. Instrument tone and timbre - #1 in importance for me - are the best I've ever heard. I believe I would almost certainly prefer it to the Monbrison (which happens to cost four times as much although that includes MC and MM phono).

You guys are way too under the radar. I am going to do my best to get the word out on this incredible machine.

(I am using some old Valve Art 2A3s which, as I said, are completely free from hum, rush, and any audible microphonic effects. I am using the recommended (by EtM) Herbie's dampers.)

(The rest of my system: Audio Note Kits DAC 3.1 Sig or Thorens 124 II into Audio Note Kits phono, custom-built WE91 300B monoblocks, Zu Definition 2.0 speakers.)"
 
Is it possible to use a Sophia 274 in place of the 5U4? The Sophia site shows this as a direct replacement with caveats:

Sophia Electric™ 274B tube is a premium rectifier tube for a 5U4/5R4/5AR4* direct replacement with 3X longer plate structure, thus it has a deeper, wider sound stage and even smoothier sound than Mullard 5AR4.

Historically, WE 274B was designed for the WE300B amp. According to a recent test, this Sophia Electric™ 274B tube outperform the NOS WE 274B by higher current capability, which translate into better bass, dynamics, and deeper sound stage.

The sonic difference comparing to conventional 5U4, 5AR4*, 5R4 is far bigger than any cable upgrades combined in a high end system.

Sophia Electric™ 274B is 8-pin octal-based tube and Sophia Electric™ 274A is 4-pin based tube.

Note(*): 274B is direct heating tube. The indirecting 5AR4 may turn on slower, however, people who buy 274B is for its superior sonic performance. To fully utilize its benefits, it may requires first stage capacitor (capacitor input) to be less than 10MFD, or would shorten the 274B life span (very much like smoking is bad for your health). It would not be a problem with common choke input. Please consult to your amplifier maker or refer to a tube manual. This 274B is an update of the NOS WE 274B, so both share with same characters. In 1930s, WE 274B was the rectifier choice for 300B single ended theater amplifier in the US.

The maximum current capability for Sophia Electric 274B mesh plate tube is 90ma, suitable for tube pre-amp and mono-block 45 single ended and 2A3 mono-block single ended.
 
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