it's 8.5 X 5.5 inches in size.
Georges post below states this as well as having a pdf of the board attached that you can print out and measure the mounting hole dimensions yourself.
https://www.diyaudio.com/forums/tubelab/331038-14-run-tse-die-17.html#post5762979
Or see post #269.
You asked about using the TSE-II as a headphone amp. I tested this briefly in post #863 of this thread:
The all DHT SET Headphone Amp
I was using 45 tubes, but plan to try some other tubes in the near future.
You asked about using the TSE-II as a headphone amp. I tested this briefly in post #863 of this thread:
The all DHT SET Headphone Amp
I was using 45 tubes, but plan to try some other tubes in the near future.
Great, thanks George.
I just sent a payment through PayPal, first step towards committing to the project
Reading up here it seems like there could be some issues with the 2A3 (or is that solved in V2?)
Would you recommend 45's, 2A3 or 300B's for a dedicated headphone amp?
I also have a bunch of other specific questions, should I ask them here or in the other thread I had started?
Thanks again
OK, I went through the "Tubes and Applications" page and am fairly convinced I want to pursue 45's.. which should be more than enough for headphones (right?)
Can anyone recommend which secondary values I need for the opt?
No strict budget here so would like to order an Electra-print, Lundahl or any recommendation.
Can anyone recommend which secondary values I need for the opt?
No strict budget here so would like to order an Electra-print, Lundahl or any recommendation.
Ideally, the secondary should reflect the impedance of your loudspeacker or headphone but a 32 ohm or higher impedance opt are rare.
I think that, with a 32 ohm headphone, you can use a 2,5K / 16 ohm transformer instead of a 5K / 32 ohm transformer.
The result should be similar.
Ashimoto,NP Acoustic (affordable amorphous core) and Partridge (vintage) can be add your list...
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I had jack wind a pair of output transformers for a single-ended headphone amplifier. I looked at the measured impedance of my headphones instead of the nominal impedance (ie 64 ohm), turns out the nominal rating of my headphones (AKG-701) is pretty spot-on. Double check to make sure this is the case for the headphones you’re going to use. Jack is also going to ask you how many watts the transformer needs to be rated for. You need to derive this from the sensitivity of your chosen headphones. If your chosen headphones aren’t too efficient, just tell him to rate the transformer at two watts.
Thanks. I currently have 2 300ohm headphones (HD650 and a ZMF), and they aren't super hard to drive.
I prefer to have multiple secondaries to accommodate any headphone changes in the future. Could I have multiple headphone jacks for each impedance (or have them switched)? Or is it a problem that not all the secondaries will be loaded at all times?
There is an OTS Lundahl LL2765 with 4.6K and 5.4K primaries and 32, 150, 600 secondaries. Any thoughts on that? Or am I better off getting it custom for my application?
Conventional wisdom says that the speaker or headphone should match the OPT, which should match the output tube, IE 3000 ohms for a 300B or 2A3 and 5000 ohms for a 45.
Most triodes will offer lower distortion when presented a higher than specified load impedance. This comes at the expense of power output. A 45 will give you 1.5 to 2 watts, a 2A3 2 to 4 watts, and a 300B 6 to 10 watts. You don't need or want watts of power on your head, a dropped needle or skipping CD can rattle your brains out. We have excess "power to burn" in these scenarios.
Headphones come in many flavors with impedances from about 24 ohms to over 600 ohms. The usual "headphone jack" on a commercial amp attempts to equalize all of this with a series resistor between the amp and cans, and maybe some load resistor across the OPT to keep the amp happy.
I must admit that I have never been a big headphone fan. My head sweats too much to wear then for long. I'm certainly not going to spend big money on something that I didn't really like. I got a cheap pair of Sony cans for use while in the car or hotel room and I have had them for about 20 years. They are light and loose enough to minimize sweating, but they are falling apart.
I got a pair of Philips DJ headphones for my desktop music studio, but sweat is such a problem with those head clamps that the foam rotted in two months.
Then I got a pair of Sennheiser open back phones.....These sound great and I can use them for an hour or two at a time. They are still on my desk after three years. I would buy another set, except the reason I got them in the first place was that Amazon was blowing out the discontinued models.
So, how do you connect up headphones to the TSE-II or any other tube amp? I did something crazy with the big Philips headspeakers. I simply connected them directly up to the OPT as if they WERE a speaker. After all they were rated for 1.2 watts each! A 32 ohm can on an 8 ohm winding will present a 20K ohm load to the tube. The 45 will be loafing along and distortion should be quite low. Power output should be several hundred milliwatts. Yes, you could hear the headphones across the room and my room is a 2000 square foot basement. Turn it down and it sounded nice. Real nice. Big bass, but these were DJ cans, probably bass heavy by design.....
I set the volume to a nice low level, yanked out the Philips cans and plugged the Sennheisers in....I have never heard them sound so good. The OPT's...they were $29 Edcor XSE-15-8-5K's. Would a better OPT sound even better? probably, but by how much?
So, this was a short experiment. It did provoke some thought, which will lead to more experiments. Ideally the tube may work better with a load closer to 5K ohms. This can easily be done by adding a resistor across the OPT secondary in parallel with the phones. One could use a 10 ohm resistor and 32 ohm phones to get a nearly ideal 8 ohm load. This would allow 8 ohm OPT's to be used, so there are plenty to choose from, and speakers could be used if so desired. That's probably where I'm going with this, but the exact resistor value will be determined by experimentation.
Most triodes will offer lower distortion when presented a higher than specified load impedance. This comes at the expense of power output. A 45 will give you 1.5 to 2 watts, a 2A3 2 to 4 watts, and a 300B 6 to 10 watts. You don't need or want watts of power on your head, a dropped needle or skipping CD can rattle your brains out. We have excess "power to burn" in these scenarios.
Headphones come in many flavors with impedances from about 24 ohms to over 600 ohms. The usual "headphone jack" on a commercial amp attempts to equalize all of this with a series resistor between the amp and cans, and maybe some load resistor across the OPT to keep the amp happy.
I must admit that I have never been a big headphone fan. My head sweats too much to wear then for long. I'm certainly not going to spend big money on something that I didn't really like. I got a cheap pair of Sony cans for use while in the car or hotel room and I have had them for about 20 years. They are light and loose enough to minimize sweating, but they are falling apart.
I got a pair of Philips DJ headphones for my desktop music studio, but sweat is such a problem with those head clamps that the foam rotted in two months.
Then I got a pair of Sennheiser open back phones.....These sound great and I can use them for an hour or two at a time. They are still on my desk after three years. I would buy another set, except the reason I got them in the first place was that Amazon was blowing out the discontinued models.
So, how do you connect up headphones to the TSE-II or any other tube amp? I did something crazy with the big Philips headspeakers. I simply connected them directly up to the OPT as if they WERE a speaker. After all they were rated for 1.2 watts each! A 32 ohm can on an 8 ohm winding will present a 20K ohm load to the tube. The 45 will be loafing along and distortion should be quite low. Power output should be several hundred milliwatts. Yes, you could hear the headphones across the room and my room is a 2000 square foot basement. Turn it down and it sounded nice. Real nice. Big bass, but these were DJ cans, probably bass heavy by design.....
I set the volume to a nice low level, yanked out the Philips cans and plugged the Sennheisers in....I have never heard them sound so good. The OPT's...they were $29 Edcor XSE-15-8-5K's. Would a better OPT sound even better? probably, but by how much?
So, this was a short experiment. It did provoke some thought, which will lead to more experiments. Ideally the tube may work better with a load closer to 5K ohms. This can easily be done by adding a resistor across the OPT secondary in parallel with the phones. One could use a 10 ohm resistor and 32 ohm phones to get a nearly ideal 8 ohm load. This would allow 8 ohm OPT's to be used, so there are plenty to choose from, and speakers could be used if so desired. That's probably where I'm going with this, but the exact resistor value will be determined by experimentation.
Thank you very much for the detailed response. I've read this through a few times... unfortunately my lack of knowledge in electronics greatly limits my ability to fully apprehend all of it.
Ok, so 5K primary as I'm going with 45's. This would also work with 300B's with slightly less power, which is a non-issue for headphones.
I was a 2 channel speaker system person for years but as life changes the only opportunities I have to sit down and listen is when the little one is sleeping. I personally don't have the ergonomics issues with headphones and they allow me to listen at whichever volume I like. I've been on the headphone carousel for a while and the 2 I currently own, the Sennheiser HD650 and ZMF Aeolus really provide 99% of what I'm looking for in terms of sound. Hearing them through the Elekit 300B amp took them to another level of realism, but that amp is reserverd for a different system... hence this 45 project.
Both headphones are rated at 300ohm and the HD650 is rated at max 500mW, and these are the ones I plan on using with this amp in the near future.
If I'm understanding you correctly, the suggestion here is that a standard 5K:8 OPT can be used, which will allow use with speakers if needed in the future. Most of the better headphone amps on the market typically have a lo/hi impedance switch which is typically 8 / 120 ohms (I think)
My budget is not restricted, so if 5K:8 is as good as any other, than great! But if there is a more optimal option given the above constraints, I would prefer to pursue that.
Ok, so 5K primary as I'm going with 45's. This would also work with 300B's with slightly less power, which is a non-issue for headphones.
I was a 2 channel speaker system person for years but as life changes the only opportunities I have to sit down and listen is when the little one is sleeping. I personally don't have the ergonomics issues with headphones and they allow me to listen at whichever volume I like. I've been on the headphone carousel for a while and the 2 I currently own, the Sennheiser HD650 and ZMF Aeolus really provide 99% of what I'm looking for in terms of sound. Hearing them through the Elekit 300B amp took them to another level of realism, but that amp is reserverd for a different system... hence this 45 project.
Both headphones are rated at 300ohm and the HD650 is rated at max 500mW, and these are the ones I plan on using with this amp in the near future.
If I'm understanding you correctly, the suggestion here is that a standard 5K:8 OPT can be used, which will allow use with speakers if needed in the future. Most of the better headphone amps on the market typically have a lo/hi impedance switch which is typically 8 / 120 ohms (I think)
My budget is not restricted, so if 5K:8 is as good as any other, than great! But if there is a more optimal option given the above constraints, I would prefer to pursue that.
FYI, the last parts order I made went from $350 at DK to under $250 when I split it between Arrow and DK, and I bought higher quantities from Arrow. And the Arrow stuff shipped free. Overnight. I honestly don't understand how they can keep it up. And their packages have 1D barcodes that you can scan without having to write Python to parse - straight into Excel, PartKeepr, partsbox.io, whatever you use.
George, if you're still considering kitting parts, just the shipping cost alone...
Disclaimer: no financial interest at all, except in saving myself money. And time.
George, if you're still considering kitting parts, just the shipping cost alone...
Disclaimer: no financial interest at all, except in saving myself money. And time.
OK I've spent hours (literally) going through the build threads and the instructions on the tubelab website. Some of the info ~may~ be outdated (the prices for some parts sure are!), and due to the many options I have follow up questions.
Sorry in advance if this is OT to this specific thread, will gladly move to the other one I started for my specific build.
Reminder: dedicated headphone amp with 45 tubes. This is an all-out build, cost is not a concern.
Here we go:
1) OPT - Electra-Print 5K, 50mA, 3W. Not sure which secondaries- Single or Dual? 8ohm? 32ohm? 120ohm? I will primarily be using 300ohm headpones but flexibility here is a plus.
2) PT - Edcor XPWR131 or Hammond 270FX ? They are the ~same price.. any preferences?
3) Choke option (yes) - Triad C-14X is 150ohm (200mA). Hammond 158M is 262ohm (100mA). Which is needed to bring B+ 280V-300V with a 4.7uF C4 cap? I'm sure there are enough people that are using a choke with 45's to get the correct values without needing to experiment here.
4) C5 - it is mentioned to use the "best" quality here. Would that be the Kemet from the latest BOM ?
5) Motor RUN cap - Seems like these vary from 20uF to 100uF. Which value is recommended? A few options here I found were
- Solen FastCap (go up to 47uF)
- ASC Capacitors X386S-40-10-440
6) Top plate aluminum panel - which thickness to support the weight?
That's all for now. Sorry for the long list!
Sorry in advance if this is OT to this specific thread, will gladly move to the other one I started for my specific build.
Reminder: dedicated headphone amp with 45 tubes. This is an all-out build, cost is not a concern.
Here we go:
1) OPT - Electra-Print 5K, 50mA, 3W. Not sure which secondaries- Single or Dual? 8ohm? 32ohm? 120ohm? I will primarily be using 300ohm headpones but flexibility here is a plus.
2) PT - Edcor XPWR131 or Hammond 270FX ? They are the ~same price.. any preferences?
3) Choke option (yes) - Triad C-14X is 150ohm (200mA). Hammond 158M is 262ohm (100mA). Which is needed to bring B+ 280V-300V with a 4.7uF C4 cap? I'm sure there are enough people that are using a choke with 45's to get the correct values without needing to experiment here.
4) C5 - it is mentioned to use the "best" quality here. Would that be the Kemet from the latest BOM ?
5) Motor RUN cap - Seems like these vary from 20uF to 100uF. Which value is recommended? A few options here I found were
- Solen FastCap (go up to 47uF)
- ASC Capacitors X386S-40-10-440
6) Top plate aluminum panel - which thickness to support the weight?
That's all for now. Sorry for the long list!
For the top plate, 0.125" (1/8") thick aluminum is usually sufficient to support the weight of the components comprising amps of this size. It's relatively stiff, strong, and easy to shape with common tools. Octal and 4-pin sockets can be cut with a 1-1/8" bimetal hole saw; use 3/4" hole saw for the 9-pin sockets.
Thank you!
I discussed this with Jack. His recommendation is single secondary. He mentions that I can either do a single 8ohm with 200hohm in series for the high impendance cans (which is similar to George's earlier recommendation), or ideally, get another 8->300ohm transformer (which seem to be smaller and cheaper). Thoughts on either approach?
OK I put some numbers in an Excel sheet and this is what I got:
8ohm secondary with 12ohm resistor across, would present loads of
32ohm - 5K
70ohm - 6K
150ohm - 7K
300ohm - 7.2K
An additional 200-250ohm resistor in series with the HP could be used for 300ohm HP's.
Question is, how much power is left to drive the HP's in this configuration, and whether the additional 8->300 transformer mentioned previously is preferred?