I am interested in building a Tubelab SE with 300b tubes as my first amp project and have a couple of basic questions.
* Can I input a CD player directly to the TSE, or do I need a preamp?
* Once built, can I swap between 300B, 2A3, and 45 tubes without changes to the circuitry?
I imagine these questions have been asked already but haven't found any answers by searching the forum. Please point me elsewhere if this is duplicative.
Thanks!
Jeff
* Can I input a CD player directly to the TSE, or do I need a preamp?
* Once built, can I swap between 300B, 2A3, and 45 tubes without changes to the circuitry?
I imagine these questions have been asked already but haven't found any answers by searching the forum. Please point me elsewhere if this is duplicative.
Thanks!
Jeff
Yes, I've read through the TSE info pages and assembly instructions on the Tubelab website, but they don't provide the answers I'm looking for.
I saw in one thread here that the SSE can accept a CD player without preamp, so I'm wondering if it's the same for the TSE.
Also, I'm pricing OPTs and am wondering how many the TSE needs. I see what look like 3 in the pictures, but not sure if those are all OPTs or if one an interstage, etc.
So far I've got the One Electron UBT-3 (for 2A3 and 300B) at $109.94 ea (https://www.tubesandmore.com/products/P-TUBT-3). Do I need 3 of these, or is it one for each channel plus something else?
I saw in one thread here that the SSE can accept a CD player without preamp, so I'm wondering if it's the same for the TSE.
Also, I'm pricing OPTs and am wondering how many the TSE needs. I see what look like 3 in the pictures, but not sure if those are all OPTs or if one an interstage, etc.
So far I've got the One Electron UBT-3 (for 2A3 and 300B) at $109.94 ea (https://www.tubesandmore.com/products/P-TUBT-3). Do I need 3 of these, or is it one for each channel plus something else?
There is one OPT for each channel, one power transformer, and optionally a choke. These are discussed in detail on a page in George's site dedicated just to transformers. That same page also answers your question about 45 vs 300B.
http://tubelab.com/designs/tubelab-se/applications/
The amp has slightly less gain than the SSE, but still enough to be driven to full output by line - level input from a CD player. Obviously, you'll need a volume control.
http://tubelab.com/designs/tubelab-se/applications/
The amp has slightly less gain than the SSE, but still enough to be driven to full output by line - level input from a CD player. Obviously, you'll need a volume control.
Thanks, I read the applications page yesterday and now understand the different voltage requirements of the tubes. My speakers are 91.5db, 2-way, 3-driver MTMs. So, I'm therefore interested in a dedicated 300b build, since it would have higher output wattage than the 2A3s or 45s.
Some of the caps and semiconductors are unavailable right now, so I've been hunting down equivalents elsewhere.
Pricing these out with Electra-Print, One Electron, and Magnequest iron, a TSE 300b build could be anywhere between $750 to over $1000 depending on tube/transformer choice.
Some of the caps and semiconductors are unavailable right now, so I've been hunting down equivalents elsewhere.
Pricing these out with Electra-Print, One Electron, and Magnequest iron, a TSE 300b build could be anywhere between $750 to over $1000 depending on tube/transformer choice.
You can but each time you adjust the volume, it will also change noise floor and can become a nuisance. If you have a receiver with analog out, just use that as pre. If not, you can try something like this.
Well, my current amp is an SS integrated Arcam A75 with a preamp output on the back. Not sure if it's digital or analog, but I wonder if a SS pre would be detrimental to the sound coming out of the tube power amp.
I guess I should really be considering a tube preamp here. Any inexpensive but good tube kits/plans/products that you'd recommend to pair with the TSE? I mostly listen to CDs as source.
I have a turntable as well, but am holding off on making a phono stage until I have a better one, unless you know a good preamp design that can take both CD and turntable.
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You can use the Arcam as a pre-amp. One thing at a time. My TSE build has sort of stalled because I bought a very early Pass Labs Aleph P pre-amp. It is a very special unit and although solid state may be one of best components I have ever owned. Designing a very good amp quite difficult, a very good preamp is a magnitude harder.
My suggestion would be that you have a firm understanding of what you are doing before starting this project. It is not rocket science but if somethings goes wrong you have to figure it out if you don't want to end up with a pile of very expensive parts.
Walt
My suggestion would be that you have a firm understanding of what you are doing before starting this project. It is not rocket science but if somethings goes wrong you have to figure it out if you don't want to end up with a pile of very expensive parts.
Walt
+1.
SS pre is likely less detrimental to the sound than tube pre. Tubes are old tech and harder to design as low distortion as SS tech. I wouldn't worry about it if I were you.
How is the room acoustics in your listening area, jdrouin?
OK, I like the idea of not having a volume control in the signal path of the TSE, and adding a tube preamp down the road when I have the time and budget, and more listening under my belt to know what I want. Btw, I'm not talking about designing a preamp, I'm talking about building one that is tried and proven to work well with a TSE that uses 300Bs.
My listening room is 20' x 12' x 8' with suspended hardwood floors. I listen across the width, with the speakers against one long wall, left of center, and the couch directly across on the other long wall. I seem to get the best sound when the couch is pulled away from the wall about a foot and the speakers pulled into the room so that there's a good 2+ feet between their backs and the wall. I measure the listening distance in this configuration at about 8' (or slightly more) from the speaker baffles to my ears.
I don't know the technical terms for room acoustics but I'm wanting to say the listening space is active, as I sense lots of reflections coming off the walls.
Because of the closeness and what I perceive to be active acoustics, I believe my modestly efficient speakers will work well with low wattage output.
My listening room is 20' x 12' x 8' with suspended hardwood floors. I listen across the width, with the speakers against one long wall, left of center, and the couch directly across on the other long wall. I seem to get the best sound when the couch is pulled away from the wall about a foot and the speakers pulled into the room so that there's a good 2+ feet between their backs and the wall. I measure the listening distance in this configuration at about 8' (or slightly more) from the speaker baffles to my ears.
I don't know the technical terms for room acoustics but I'm wanting to say the listening space is active, as I sense lots of reflections coming off the walls.
Because of the closeness and what I perceive to be active acoustics, I believe my modestly efficient speakers will work well with low wattage output.
Jdrouin,
I faced the same problem, like you I'm finishing a TSE with 300B with UBT-2
As for preamp, a couple of years ago I built a low-mu preamp by Pete Millett
Low-mu preamp
and these days I'm coupling together, seem that match pretty well.
I'm strongly interested in the PassLab preamp too.
My loudspeakers are self built using Jordan Eikona and a Cornu configuration
http://www.diyaudio.com/forums/full...k-building-cornu-spiral-horn-now-you-can.html
I'm not an expert but available to help.
Good luck
I faced the same problem, like you I'm finishing a TSE with 300B with UBT-2
As for preamp, a couple of years ago I built a low-mu preamp by Pete Millett
Low-mu preamp
and these days I'm coupling together, seem that match pretty well.
I'm strongly interested in the PassLab preamp too.
My loudspeakers are self built using Jordan Eikona and a Cornu configuration
http://www.diyaudio.com/forums/full...k-building-cornu-spiral-horn-now-you-can.html
I'm not an expert but available to help.
Good luck
Thanks for the links on room treatments, Evenharmonics, and the Millet preamp, gmonno. The DIY Audio Projects site offers the 4S Universal 12A*7 preamp project that looks interesting, too. Once I'm done studying Morgan Jones's Valve Amplifiers, I'll make a decision based on what I've learned.
Also, I wonder if this stepped attenuator project would work well as a passive volume control between CD Player and the TSE.
Also, I wonder if this stepped attenuator project would work well as a passive volume control between CD Player and the TSE.
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