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My plan is to build the TS-Phono, Masterpiece, & SOB. As my 600+ LPs await a turntable & cartridge I will be purchasing either the MP or SOB in the next few days. I have a few questions that remain as my topic search of this forum returned no results. So I thought I might have some luck asking the experienced TS Community. 1. Based on ease of build, as I'm rusty, which should I start with SOB or MP? 2. Concerning heat, would heat sinks applied to the entire sides of the SOB and / or MP chassis be beneficial? 3. Even with AC the house can get damp here in SW Florida. Would painting the steel chassis to prevent rust have any detrimental effects? 4. The sight of Tubes is pleasing to my eye however the bare transformers no so much. Can "cans" be used without any heat or electromagnetic issues? Thanks in advance to any and all who choose to offer their experience and expertise to a "newbie" Sincerely, Jim
Reply with quote #2
Jim. I have built a number of Bruce's amps including the Masterpiece and the SOB, though the latter I built straight from Tubes and Circuits rather than from the kit.
In my opinion I would say the Masterpiece is the simpler build as there are only four tubes involved. Bruce's instructions are extremely clear and easy to follow so you would be OK either way. Just take your time. These amps do need air space to breathe as they do run quite warm, but I do not think you would need extra heat sinking especially as you have air conditioning. I understand some folk drill extra holes along the edges near the toroids and this would obviously help in keeping things a bit cooler. If you do add extra heat sinks to the sides be sure not to allow contact with the bolts securing the regulators on the MP as they are isolated from ground. As far as I am aware the chassis on TS amps are alumin(i)um so there should not be any corrosion problems. It is quite damp here at times in Glasgow, Scotland! Personally, I would not cover the toroids. Let them breathe. I do not see any electromag problems as toroids have limited external fields. I am sure others will have further tips for you. You are setting out on a very rewarding path. Kelvin
Reply with quote #3
Originally Posted by
Jim J 1. Based on ease of build, as I'm rusty, which should I start with SOB or MP? I would start with the MP. As Kelvin has said, it is simpler but also, you'll be able to sample the TS 'sound' via headphones while you progress the SOB.
Originally Posted by
Jim J 2. Concerning heat, would heat sinks applied to the entire sides of the SOB and / or MP chassis be beneficial? They're not necessary, otherwise Bruce would have specified them. Remember, the tubes themselves run hot regardless of the chassis.
Originally Posted by
Jim J 3. Even with AC the house can get damp here in SW Florida. Would painting the steel chassis to prevent rust have any detrimental effects? The Transcendent chassis are Aluminium. In a hostile environment this can corrode (a white powdery appearance) but I suspect they will be fine even in a tropical region. You could always consider getting the chassis anodised if you're worried, which might also give you some interesting colour options.
Originally Posted by
Jim J 4. The sight of Tubes is pleasing to my eye however the bare transformers no so much. Can "cans" be used without any heat or electromagnetic issues? I also dislike exposed transformers. For my builds, whenever a transformer is to be located externally to the chassis I have it potted; this entails putting them into a container (normally plastic) which is then filled with a special compound that totally encapsulates the transformer. As long as the transformer is suitably rated (so it's not running close to its current rating and thereby getting too hot) there is not a heat problem. Toroids has very localised fields so I don't think that you'll have electromagnetic issues and I've not experienced any with my potted toroids. One thing to be aware of if you consider potting your toroids is that it, obviously, increases their physical footprint so you may need to mount them is slightly revised positions on the chassis. These are the toroids for my scratch built 300B SE-OTL to show you what I mean; Ray
Reply with quote #4
The hardest thing about the build is getting a good solder joint on solder strips. An adjustable temp soldering iron will help greatly with this. Use recommended solder. High on strips lower on sockets and other parts not attached to strips. But in any case use a little wire and a solder strip and practice before you start. Mark each step as completed and go over every step from beginning to end before your first fire up. And very important make sure you install the 300B into there socket correctly. They can be installed wrong with some bad consequences. The easiest part to destroy is the selector switch. Use low heat on that part. Would not paint the chassis. When built well Bruces equipment is the most dependable of all tube stuff. My T. count is 6 kits and 3 scratch. Good luck on the build.
Reply with quote #5
Personally, I would be a bit wary of anodizing the chassis of the Masterpiece. Anodizing results in an insulating layer on the surface and the MP uses the chassis as a ground plane. It would be essential to make sure all the tag strips' ground lugs were really electrically connected to the chassis. I have seen problems with this previously.
Reply with quote #6
Originally Posted by
Kelvin Tyler Personally, I would be a bit wary of anodizing the chassis of the Masterpiece. Anodizing results in an insulating layer on the surface and the MP uses the chassis as a ground plane. It would be essential to make sure all the tag strips' ground lugs were really electrically connected to the chassis. I have seen problems with this previously. Kelvin Agreed and I should have mentioned it.
Reply with quote #7
TS-Phono, Masterpiece, & SOB (scratch build from T&C) I run this exact set up along with two of Ed's buckets...only issue I have is I can't stop wondering how the Pinnacle or SE 300B could possible make this set up any better. ok, second issue I have is...9 o'clock on the MP is too loud for my wife and 12 o'clock is too loud for me (running a 2.5mV MC Blue Point no. 2)
Reply with quote #8
Do you have SQ issues at 9 o'clock position?
Normally SQ in High End translates (among other things) to how good soundstage, tonal integrity, size of instruments are kept at different volume levels (also depends on the speakers you use). I think TS amps are very good in this respect.
But if you feel that at 9 o'clock a piano for example appears smaller in size than at 12 o'clock or the overall sound is less transparent or instruments change their "normal" size compared to each other I would try first 2 things which won't affect the integrity of the circuit.
First I would use some smaller value for the output resistor to ground and check how this affects your problem.That costs nothing and could work.
The better but more expensive thing you could do is to use a very high quality stepped attenuator with at least 1dB steps. That would affect SQ less at low volume levels than the original pot.
A third possibility could be to decrease the value of the NFB resistor a little but that can affect other things in the circuit and the MP already sounds pretty much on the "clean" side. Maybe more NFB would be too much?
And to your first question: different amps like the 300B OTLs would improve those qualities like sound stage, tonality, size of instuments etc. as I have found out in a most dramatic way with my 300B SE DC OTLs. Many years back I used Mark Levinson amps with Revel Ultima Studio speakers and one of the most outstanding features was how they kept the integrity of the music/size of instruments from low to high volume levels. But they lost a bit of their clarity/high resolution at lower volumes. Since I use Lowther BLH with TS amps that problem has disappeared almost completely.
Reply with quote #9
Build the kits as is, get the Alps volume pot upgrade, or a stepped attenuator. You will be very happy.
The build is pretty straight forward, and Ill second those that recommend an adjustable soldering iron.
Reply with quote #10
First, thanks to all who took the time to reply to my original post. It all helped me make some decisions.
1. I will build the preamp first as suggested and as Bruce intended (fingers crossed for luck) with No modifications except the chassis will be highly polished. 2. No "Cans" on the transformers, however the pictures provided look plenty sweet for sure! ... nice job! 3. Ordered a new Hakko soldering station with temp adjust. I'm posting this as my Masterpiece Kit just arrived today from Bruce and am excited to get started. I have read the instructions and my confidence level has already increased. Looks straight forward, maybe a slight bit tedious here and there, but it appears Bruce has illustrated and explained everything in nice step-by-step detail. "By the inch it's a cinch... By the yard it's hard" kind of thing. The chassis is much nicer than expected, not flimsy or science project like as suggested on some other forums. All holes and cut-outs appear to have been laser cut and a ventilated bottom panel is provided which is not mentioned or shown in any photos, gotta like that! It appears as sturdy as anything McIntosh has produced. But I have a few more questions before I get started and they are as follows; 1. Plan on using WBT 4% Silver Solder on all but terminal strips. Is 1/8 lb. sufficient for this project? 2. Kester 44 rosin core for the terminals. 63/37 or 60/40 in .02, .031, or .05? 3. From Antique Electronics the JJ 300B tubes, should I order them "Matched"? Does it matter? 4. Which brand for the 12AU7s? Any feedback appreciated. Jim
Reply with quote #11
Jim. I have built two Masterpiece pre-amps now. What follows are simply my personal preferences.
1. I never use silver solder on electronic projects. I use Ersin Multicore 60/40 Sn/Pb at 1.2mm (0.05"). Here in the UK a 500g reel costs £30-40. Enough for several such projects. 3. I have used Electro Harmonix Gold 300B. About £150 here for a matched or unmatched pair. Get matched. JJ a bit more pricey here, but will also be OK. 4. JJ regular 12AU7 tubes at £11 each work fine. Happy building, Kelvin
Reply with quote #12
Seems as though your onion on using silver solder is in the majority. I will take your advice and save some $$ as well.
Reply with quote #13
Jim, You will love the Hakko soldering station. It comes up to temperature blazing fast compared to a standard soldering iron. The biggest chisel tip for the solder strips and a smaller one for the circuit boards works well for me. The presets are super convenient for changing temperature. Highly recommended!
Reply with quote #14
Yes, Hakko are great. Never bothered with silver solder myself either.
If you're shopping at AES/Amplified Parts, there's a sale on thru July 5th. You can get very nice NOS 12AU7 types for $15 each or less if you shop around, which would be my choice. Don't forget the 'lesser known' types like 5814 or 6189. Take some time to study the manual carefully. Even though I've done quite a few projects, for this one I made up a simple spreadsheet with the terminal numbers & how many connections there were on each, that way I didn't solder until all the connections were attached to a terminal.