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Old 3rd September 2011, 08:28 PM   #221
Desmo is offline Desmo  Denmark
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Hi Thorsten... Do you happen to have the scematic for the UVC in the Tram II..?

I would like to dim the blue LED's for the input selector and the volume, they are way to bright for my liking. I suppose there is a voltage drop resistor between the supply and the LED's that can be replaced with a larger value?

Thanks,
Morten
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Old 4th September 2011, 03:49 AM   #222
Previously: Kuei Yang Wang
 
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Hi,

Quote:
Originally Posted by Desmo View Post
I would like to dim the blue LED's for the input selector and the volume, they are way to bright for my liking. I suppose there is a voltage drop resistor between the supply and the LED's that can be replaced with a larger value?
The Resistors are R8 & R11, original 390 Ohm.

They are one each on the actual controls section (with LED's and rotary encoder) of the PCB.

Ciao T
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Old 4th September 2011, 07:44 AM   #223
Desmo is offline Desmo  Denmark
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Thank you for another fast reply Thorsten! It's so good to have you here to help us Tram II owners :-)

Thanks,
Morten
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Old 8th September 2011, 03:13 PM   #224
Desmo is offline Desmo  Denmark
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Quote:
Originally Posted by ThorstenL View Post
Hi,



The Resistors are R8 & R11, original 390 Ohm.

They are one each on the actual controls section (with LED's and rotary encoder) of the PCB.

Ciao T
Just to give an update on this for other Tram owners...

I have replaced the 390 ohm resistors with 2K ohm ones. IMHO this is a good balance: They are visible in day light, and not too bright at night...
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Old 24th September 2011, 02:28 AM   #225
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I have a funny behaviour of my last assembled Tram. On the start-up volume/selector board occasionally refuses to start. I have the valves working but no lights on the volume/selector boards. Power cycling usually fixes the problem. The controller chip is V2.1 - any insights?

Did not have this with other Trams that I assembled.
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Old 24th October 2011, 08:18 PM   #226
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Any happy Tram owners lurking here? No issues for months, etc?

I've just ordered my 2nd Tram. The first had issues but was ultimately reliable after replacing some parts. I see people reporting issues recently but it seems it might be other things to blame in perhaps all cases (bad tubes, bad mains V).

I see talk of biasing now which is odd to me because my unit was autobias. At least I sure thought it was. Did that change?
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Old 25th October 2011, 09:45 AM   #227
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My Tram II is running fine.

I've been doing some tube rolling, spurred on by Morten's experiments. I was surprised to find the Mu tube has a noticeable sonic impact (the voltage stayed at close to 120V).

Chinese Mu + US Army 5U4 rectifier + Cunningham 2A3s
- Intimate sound
- Glassy edge - similar effect to microphonics, I had compensated for this elsewhere in my system

Svetlana Mu + Svet 5U3 + Cunningham 2A3s
- Rich and fullsome
- Good bass impact
- Tuneful mid / upper bass
- some mid sounds, eg piano, more distinct than with my 45s

Chinese Mu + Svet 5U3 + Cunningham 2A3s
- still a touch glassy, the Chinese Mu and US Army rectifer have similar characteristcs

Svetlana Mu + Svet 5U3 + Sylvania 45s
- Smooth
- Bass not as agile or powerful as the 2A3s

The Sylvania 45s measure well and are quiet - my other old 45s are noisy so it's great to have a some good 45s at my disposal.

The rolling sessions show how important it is to get the right balance across all 4 tubes with the Mu tube being more important than I had expected.

Last edited by clivetjm; 25th October 2011 at 09:56 AM.
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Old 25th October 2011, 02:04 PM   #228
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Thanks, Clive! That is very helpful.

[In my system previously I was pretty amazed to find the Tram held its own in most ways against a $9K Tom Evans Vibe/Pulse and exceeded it in some. Of course it was not *quite* as extended and tight on the bottom as that piece but what could one expect? The Tram remains my favorite tube linestage of all time and, boy, I have tried a lot of them.]
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Old 26th October 2011, 10:45 AM   #229
Desmo is offline Desmo  Denmark
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Yes, the Mu tube does for sure make a difference..! And if you're after a more tight bass I suggest trying out different Mu tubes. As you can see in the tube-rolling threads here on the forum I have tried several different tubes for all the positions in the Tram II. The biggest difference is the triodes for sure, but like Clive, I have experienced noticable differences in sound with different Mu tubes.

The NOS Svetlana's has a richer and more full sound, especially in the bass and midrange.

The NOS Cunningham I have are tighter and leaner compared to the Svetlanas.

For now I'm using Treasure 2A3-Z triodes, RCA 5R4GY rectifier and Cunningham 6AS7 Mu tube. In my system, that is a nice balance... If I use the same Rectifier and Mu tube together with my Sylvania 45's the sound get's too lean. So when using 45's as triodes I use the Svetlana rectifier and Mu tubes for their added richness and their more full sound in the bass...

Bottom line: You better roll all four tubes to get the best balance in your own system..!
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Old 5th November 2011, 08:19 PM   #230
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I just wanted to say that my new Tram is incredible. I don't know what was changed, but it is nearly completely silent, and I have NO microphonics issues even *without* tube dampers with either new Valve Art 2A3s or NOS 45s.
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