Coleman Regulators are an aftermarket upgrade - they come as a DIY self assembly kit, available separately from me (send me some email - click on my name). They can easily to set up to work with 2A3/45 or 4P1L.
TRAM requires very low noise and more isolation between the music signal & the regulator - which these regulators are designed to offer.
TRAM requires very low noise and more isolation between the music signal & the regulator - which these regulators are designed to offer.
Josh
If you have a factory built unit it will have the DiyHiFiSupply DHT filament regulators fitted. They will either be the early ones, which were ok with 45 but prone to overheating and dying with 2A3 - they can be seen in Desmos post #84
or they will be the later versions which are more stable with 2A3, which can be seen here:
An externally hosted image should be here but it was not working when we last tested it.
Neither of these original filament supplies is as quiet or as musically satisfying as Rob Coleman's supplies. They are strongly recommended by everybody on here who has fitted them, but they are some work to install....!
You need a pair of kits from Rod, which need to be mounted carefully to address heat dissipation - directly to the chassis, or using a heat spreader, or fitting additional internal heat sinks.
You will also need to build a pair of "raw dc supplies" to feed the Reg boards. These can use the two 7V filament windings on the Tram mains transformer, and Rods instructions gives a lot of guidance about designing the raw dc supply. I used Schottky diodes to make a bridge, and BHC ALS30 series caps.
Desmo fitted his first, see post #314
then GeirT in post #438
whilst I just rode off the back of their experience in post #823
and rab28 has his setup in post #882
There are a bunch of other suggestions for improvements buried throughout the thread, probably the two key ones are:
- use the volume control in shunt mode, and replace the metal film resistor with your favorite audio type - Desmo used naked bulk foil, I used tantalum film
- replace the trimmers on the CCS board with 25 turn units, makes stabilizing the amp sooooo much easier
other than that you can swap out the resistors and coupling caps if you have a preferred type.
Having had two units, one with 2A3 and one with 45, I would say that it can be a really great sounding amps when fully tweaked. I had a preference for the 45 unit I had, it was cleaner and fleeter of foot, but that could be partially down to the basic chinese 2A3 compared to the NOS 45 which were used.
Best of luck
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Huge thumbs up sjs! That really helps. I bought mine factory made later on after the newer regs were in it, iirc. The problem with parsing this thread is also down to the fact that there were different versions and that some people were building kits versus some buying factory built, so it is sometimes hard to judge whether somebody was just modding the original kit or substituting, etc.
I think I have it sorted now. I think this preamp is quite lovely in most ways but I notice it is quite noisy while warming up (not the biggest deal breaker) and then settles down to only ever so slightly noisy/microphonic. I broke down and bought EML 45s (reg ones) and they aren't any less noisy than my OS 45s. I had read a couple of places that Coleman's regs cut down noisy but also microphonics, so I am going to order some of the kits.
Josh
I think I have it sorted now. I think this preamp is quite lovely in most ways but I notice it is quite noisy while warming up (not the biggest deal breaker) and then settles down to only ever so slightly noisy/microphonic. I broke down and bought EML 45s (reg ones) and they aren't any less noisy than my OS 45s. I had read a couple of places that Coleman's regs cut down noisy but also microphonics, so I am going to order some of the kits.
Josh
Hi guys,
Just on a side note, I am running my tram with Coleman regs and eml 45 globes into some very efficient horns and there was still some noise. After talking with some friends I decided to change the 10uf obbligato that grounds the b+ supply for some 20uf solen pb caps.
The effect was dramatic! Lower noise floor, wider, deeper and more liquid. I then did this for rab28 and Bryan's with a before and after comparison: same result very cheap so give it a try. One other tweak is to point to point wire the CCS and invert it and fix the trimmer to the the chassis with a small hole for for adjustment. This is great as you then don't have to turn it over and as the chassis acts as a heat sink it seems to keep the trimmer from drifting.
I too am thinking of trying the 4p1l if possible...........
Just on a side note, I am running my tram with Coleman regs and eml 45 globes into some very efficient horns and there was still some noise. After talking with some friends I decided to change the 10uf obbligato that grounds the b+ supply for some 20uf solen pb caps.
The effect was dramatic! Lower noise floor, wider, deeper and more liquid. I then did this for rab28 and Bryan's with a before and after comparison: same result
very cheap so give it a try. One other tweak is to point to point wire the CCS and invert it and fix the trimmer to the the chassis with a small hole for for adjustment. This is great as you then don't have to turn it over and as the chassis acts as a heat sink it seems to keep the trimmer from drifting. I too am thinking of trying the 4p1l if possible...........
I realised looking at the Tram2 internal photos again, most appear to have the "optional" electrolytic cap wired into the power supply board.
On both the units I had this "optional" cap wasn't required, and out of circuit the sound climbed several levels of clarity and detail. Just like removing the last 'lytic cap in fact!
On both the units I had this "optional" cap wasn't required, and out of circuit the sound climbed several levels of clarity and detail. Just like removing the last 'lytic cap in fact!
Can the Tram2 be adapted for different DHT's like the 4P1L?
Could it be a low gain tube like the #26 tube might be best to improve the SNR for a preamp?
2x 4P1L PSE will run 250V 60mA, so will substitute 2A3 pretty well, and probably better quality than most 2A3s.
Will 2x fit in the box?
You have Coleman regulators, so just change Regulator R1=R2=1.5 ohm wirewound, and adjust the current to give 1100-1180mA (slightly low, to reduce microphony). The Regulator's trimmer makes it easy to try different current vs microphony level. Please see the "4P1L preamp" thread on tubes/valves for tricks like mounting the valve socket on rubber mounting bushes. TRAM trafo's 7.5V heat winding and 2A3 raw dc for filaments will be OK for 4P1L or 2x 4P1L.
Will 2x fit in the box?
You have Coleman regulators, so just change Regulator R1=R2=1.5 ohm wirewound, and adjust the current to give 1100-1180mA (slightly low, to reduce microphony). The Regulator's trimmer makes it easy to try different current vs microphony level. Please see the "4P1L preamp" thread on tubes/valves for tricks like mounting the valve socket on rubber mounting bushes. TRAM trafo's 7.5V heat winding and 2A3 raw dc for filaments will be OK for 4P1L or 2x 4P1L.
Rp of 26 is probably too high to use in Tram2, but 71A could be a possible alternative if you can sort out the filament supply and the negative bias supply. The Tram2 runs the dht with Vp of 120v, which is ok for a 71A.
May be worth investigating, but not sure if they will have lower noise or microphony than a good 45.
May be worth investigating, but not sure if they will have lower noise or microphony than a good 45.
I wonder what is the max Rp the Tram2 could handle and why please?
I wonder what the Rp of the 4P1L is in triode mode? Maybe Klaus worked it out?
I wonder what the Rp of the 4P1L is in triode mode? Maybe Klaus worked it out?
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Hi everyone - and I'm sorry that I have not been participating for quite some time...
Truth is actually, that I feel that I'm kind of ''growing out of hifi'', this is a strange feeling after 30 years with music, hifi, DIY etc etc, but I have come to the conclusion, that it's time to move on to other ventures. I'm playing the bass in a band, and I spend more and more time with the band than in front of my hifi system. I have also started building bass guitars myself, and I find it so rewarding to be working with exotic woods instead of electronic components... Luckily it's still all about music though
This also means, that I'm selling my big high end hifi system. I just want a small and simple system from now on, that better match my needs, and my limited use of the system.
So if anyone is interested in my Tram II and my The Vinyl Song LCR phono stage - let me know - send me a pm. As you know from this thread I have spend endless hours (and money) to get the Tram II to the max, same goes for the phono stage with the amzing Hashimoto step-up's and more. I have a ton of tubes also, including the very expensive, and extremely good sounding Full Music 2A3/SE.
A ''warning though'' I'm not giving away this stuff after investing so much in them, they will cost a good deal of money. I only sell the preamp and phono stage together, and I'm only selling to someone who I can feel will love to own them. Otherwise I will keep them and build up a smaller system around the two little black boxes...
Thanks,
Morten
Truth is actually, that I feel that I'm kind of ''growing out of hifi'', this is a strange feeling after 30 years with music, hifi, DIY etc etc, but I have come to the conclusion, that it's time to move on to other ventures. I'm playing the bass in a band, and I spend more and more time with the band than in front of my hifi system. I have also started building bass guitars myself, and I find it so rewarding to be working with exotic woods instead of electronic components... Luckily it's still all about music though
This also means, that I'm selling my big high end hifi system. I just want a small and simple system from now on, that better match my needs, and my limited use of the system.
So if anyone is interested in my Tram II and my The Vinyl Song LCR phono stage - let me know - send me a pm. As you know from this thread I have spend endless hours (and money) to get the Tram II to the max, same goes for the phono stage with the amzing Hashimoto step-up's and more. I have a ton of tubes also, including the very expensive, and extremely good sounding Full Music 2A3/SE.
A ''warning though''
I'm not giving away this stuff after investing so much in them, they will cost a good deal of money. I only sell the preamp and phono stage together, and I'm only selling to someone who I can feel will love to own them. Otherwise I will keep them and build up a smaller system around the two little black boxes...Thanks,
Morten
Attachments
Thanks guys, I appreciate your feedback... I really do...
And it's not that it's like ''no more music and hifi'' for me. I will continue listening to music, and I will expect good sound from my system and all that. After 30 years I have just lost the interest for sitting hour after hour in front of my stereo listening to music... I work with music and DIY in other ways now, so I can't justify having so much money invested in stuff that I hardly ever use anymore.
I have always loved learning something new and working with DIY. I find it very rewarding to learn about building instruments. There is so much more going on with this than just ''slapping pieces of wood together'' and there is so much craftsmanship involved. And so much creativity and design... I love it..!
Here are some pictures of a bass neck in progress that I'm working on right now, where I have managed to make my first so called ''scarf joint neck''. Not easy, but it worked out. And the last two pictures is of a chambered bass body I made for another bass. Very cool (I think), and sorry for the off topic
And it's not that it's like ''no more music and hifi'' for me. I will continue listening to music, and I will expect good sound from my system and all that. After 30 years I have just lost the interest for sitting hour after hour in front of my stereo listening to music... I work with music and DIY in other ways now, so I can't justify having so much money invested in stuff that I hardly ever use anymore.
I have always loved learning something new and working with DIY. I find it very rewarding to learn about building instruments. There is so much more going on with this than just ''slapping pieces of wood together'' and there is so much craftsmanship involved. And so much creativity and design... I love it..!
Here are some pictures of a bass neck in progress that I'm working on right now, where I have managed to make my first so called ''scarf joint neck''. Not easy, but it worked out. And the last two pictures is of a chambered bass body I made for another bass. Very cool (I think), and sorry for the off topic
Attachments
WTB - Tram Volume Boards
Does anyone have spare front and rear output boards they are willing to sell sale? Secondhand OK, providing they work.
My RVC has failed and to be on the safe side I'd like to replace both boards. The volume control turns, but no sound comes out.
I've tried contacting DIY Hi Fi Supply - they replied the first time to say they had the boards in stock, but haven't responded to my subsequent emails.
Does anyone have spare front and rear output boards they are willing to sell sale? Secondhand OK, providing they work.
My RVC has failed and to be on the safe side I'd like to replace both boards. The volume control turns, but no sound comes out.
I've tried contacting DIY Hi Fi Supply - they replied the first time to say they had the boards in stock, but haven't responded to my subsequent emails.
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