Speaker amps for headphones
Sep 1, 2020 at 11:00 PM Post #3,301 of 3,682

pataburd

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Thank you very much.
Your pictures are very helpful.
How did you calculate the resistance load based on the headphones in use?
Is there a formula?
Thanks again.
 
Sep 1, 2020 at 11:28 PM Post #3,303 of 3,682

kid vic

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Are you driving the cans straight off the taps without any resistor in place? I've always been under the impression that one should not drive headphones directly off the speaker taps of a transformer coupled tube amp. Or am i wrong to think as such?
I would contact the manufacturer and ask them as the amps design may be ok with this; however, it is possible that you are straining your amp. This little thread early on covers the basics of this.

https://www.head-fi.org/threads/safe-to-drive-headphones-with-tube-speaker-amp.680786/

I had thought so earlier in this thread but I couldn't remember the exact reasoning. Glad someone else could clear it up.
 
Sep 2, 2020 at 5:13 AM Post #3,304 of 3,682

pataburd

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Like this?
The HEDDphone are 42 ohms, Target is 8 ohms for the Sophia Baby.

errs on the side of "too little"
1599038360882.png






errs on the side of "too much".
1599038276485.png

Which error is "better"?
[Thank you for your patience.]
 
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Sep 2, 2020 at 6:32 AM Post #3,305 of 3,682

AnaKinDV8

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Finally got this underway. After a couple of weeks using conventional headphone amps the Conductor 3R and the Beta22, found the 1266TC's lackluster and really disappointing. I thought it would have at least a decent match with the Burson, but for all its 6W the TCs seemed underpowered (no dynamics, no detail, overly warm). Plugged the TC into my stereo setup (Cantata CD/DAC > Pass XP10 > X150.5 via XLRs) using the Furutech adapter, the sound seemed too loud (too much gain?).

I am now testing the following configurations:
Burson C3R (as DAC-preamp) > X150.5 > 1266TC via RCA - better than all the above setups, skipping the XP10 preamp and running the Burson direct to the X150.5 seems to have scaled the power to the level of the headphones (not sure if that makes sense). It also let the ESS DAC shine with it's detail and resolution, with the power of the amp that just totally controlled the TCs - very good dynamics, deep impactful bass.
Cantata (as DAC-preamp) > X150.5 > 1266TC via XLR - the Cantata and the balanced connection outperformed significantly the Burson C3R setup. Replacing the technical ESS sound with R2R musicality while matching the detail and resolution. This is the best configuraion I've tried yet for the TCs and I'm finally able to experience the Abyss sound that I've read so much about.

So far I've been fortunate to have 2 DACs which have pre-amp functions allowing me this direct to amp configuration. Having all this clean power at the disposal of the DAC really shows the character and strengths of the source and the 1266TC's are really able to sing. Volume has not gone beyond 40 in both cases. I'm not sure I would still be exploring dedicated headphone amps for the TCs having experienced what a real good amp can do with it. I doubt even the Formula S or the HPA 4 can deliver this kind of control of the drivers, natural sounding visceral bass and almost stereo-like soundstaging. I'm looking more towards upgrading to an XA25 (20W Class A) or a First Watt F7, for even better transparency and musicality but because this doubles as the amp for my stereo, that won't be happening until I can switch to high-efficiency speakers.

20200902_163615.jpg
 
Sep 2, 2020 at 8:31 AM Post #3,307 of 3,682

pataburd

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Yes, just get 2 10-ohm resistors, 1/channel.
Thank you very much!
Hope I didn't damage the transformers in a 3 hour fit of wreckless abandon!
 
Sep 2, 2020 at 3:26 PM Post #3,309 of 3,682

kid vic

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Yes, just get 2 10-ohm resistors, 1/channel.
I have a Scott 299D tube amp and I want to run my planars off of the speaker taps. It has 4, 8 and 16ohm taps on the back; problem is, I have three pairs of headphones (HE500, lCD3, EF1.1) and will add more later. Would the HE-adapter work for all of them?
 
Sep 2, 2020 at 6:31 PM Post #3,310 of 3,682

pataburd

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wuhere, kid vic, et al,
Picked up two [generic] 10 ohm resistors [to tide me over until the Mills arrive] and hooked them up.
Everything sounds a lot better. Bass response is now phenomenal and things don't sound so "hot" and overly laser-focused.
I am so impressed, and so grateful, and so relieved!
Thankee, everyone!
pataburd
IMG_20200902_180519127[1].jpg
 
Sep 2, 2020 at 7:14 PM Post #3,311 of 3,682

wuwhere

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I have a Scott 299D tube amp and I want to run my planars off of the speaker taps. It has 4, 8 and 16ohm taps on the back; problem is, I have three pairs of headphones (HE500, lCD3, EF1.1) and will add more later. Would the HE-adapter work for all of them?

I thought the HE-adapter was designed for HE-6 but I could be wrong. I think it is also for the 8-ohm tap on your tube amp. From what I can remember, I believe it also has an over-current protection. There is a small resistor that would burn if there is too much power draw. This can happen if you forget to turn down the volume. Happened to me once. The volume on my 60 watt tube was all the way up. It didn't damage my HE-6. Most of the power is actually used by the 10-ohm resistor. So there is some protection there.
 
Sep 2, 2020 at 7:26 PM Post #3,312 of 3,682

wuwhere

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Resistors also have different power ratings and inductance. So buy the 5-watt instead of the 10-watt. Also the lowest inductance or no inductance. But there is really no such thing as no inductance. Its just so low that it is not audible. And from what I understand, only the frequencies way above 20kHz are affected.
 
Sep 2, 2020 at 8:51 PM Post #3,313 of 3,682

kid vic

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I thought the HE-adapter was designed for HE-6 but I could be wrong. I think it is also for the 8-ohm tap on your tube amp. From what I can remember, I believe it also has an over-current protection. There is a small resistor that would burn if there is too much power draw. This can happen if you forget to turn down the volume. Happened to me once. The volume on my 60 watt tube was all the way up. It didn't damage my HE-6. Most of the power is actually used by the 10-ohm resistor. So there is some protection there.
Yeah, fully aware that it was made for the HE-6 but I don't have one at the moment.

With the headphones I currently have the gain is to low out of the headphone jack; meaning, my LCD3, EF1.1 and TH600 all require the volume knob to be at about 12 for decent listening for a line level and at 2 or 3 for phono. The HE500 is worse. Maybe taking the amp to a tech and seeing if they can raise the gain is an option?
 
Sep 2, 2020 at 9:01 PM Post #3,314 of 3,682

MachineGunz

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Hi,

I might sound a bit dense and stupid haha.

How do you handle the switching between speakers and headphones? I was thinking of buying a speaker amplifier for my headphones in the future but it's an absolute nightmare to always switching the banana plugs from speakers to headphones.


I was wondering if it is possible to connect both the speakers and the headphones to the speaker taps at the same time with some kind of splitter or a slitter console - And of course having the choice to listen to them separately.
 
Sep 2, 2020 at 9:02 PM Post #3,315 of 3,682

wuwhere

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Yeah, fully aware that it was made for the HE-6 but I don't have one at the moment.

With the headphones I currently have the gain is to low out of the headphone jack; meaning, my LCD3, EF1.1 and TH600 all require the volume knob to be at about 12 for decent listening for a line level and at 2 or 3 for phono. The HE500 is worse. Maybe taking the amp to a tech and seeing if they can raise the gain is an option?

I believe they use a network of resistors to bring down the power at the headphone jack. Not sure about the gain though. You may need the amp's schematic. Don't know if you can get it on-line.
 

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