No answers, just pointers...
First you have to decide if headphones are better than speakers. I feel that is probably down to how much you value sounds being generated outside of your head (speakers) verses 'inside' of your head as it can sound with headphones.
Then it comes down to economics... because the best headphones sure cost much less than the best speakers!
As for headphone amps there is a lot of dross at the low end of the commercial market, sold simply to shift boxes and generate cash rather than make money by providing decent performance.
The commercial top end is typical audiophile 'status symbol' stuff... and typically over-hyped by the egotists and internet 'gurus'.
If you go DIY vacuum tube you will need an output transformer to get a sensible low output impedance, and any design without a transformer (i.e. typical cathode follower type) will likely be inaccurate when driving headphone impedances.
If you use modern high efficiency 'phones you will not need much signal level for good volume, and hence you can get a good low distortion characteristic from a parallel-feed transformer-coupled 6H30.
As for solid state, 99% of designs seem to wrap an output transistor in the feedback loop of an op-amp. The figures look good on paper, but I've known many folks whine about the sound quality. (But I'm obviously generalising here).
At the moment I think one sensible approach would be to buy one of the new S c h i i t Asgard amps (about $250 in North America, but will be more by the time they reach our shores), and then modify it with an external mains transformer, a decent volume control, and more ventilation holes. (Just a shame about the adolescent 'look at me, look at me' company name. Oh well).
As for solid state DIY builds, there sure is plenty to dig into on this forum via the search facilities, and also consider the neat open-loop Cavalli-Kan Kumisa 3, which is detailed here: The Cavalli-Kan Kumisa III Stereo Headphone Amplifier.
Good luck
First you have to decide if headphones are better than speakers. I feel that is probably down to how much you value sounds being generated outside of your head (speakers) verses 'inside' of your head as it can sound with headphones.
Then it comes down to economics... because the best headphones sure cost much less than the best speakers!
As for headphone amps there is a lot of dross at the low end of the commercial market, sold simply to shift boxes and generate cash rather than make money by providing decent performance.
The commercial top end is typical audiophile 'status symbol' stuff... and typically over-hyped by the egotists and internet 'gurus'.
If you go DIY vacuum tube you will need an output transformer to get a sensible low output impedance, and any design without a transformer (i.e. typical cathode follower type) will likely be inaccurate when driving headphone impedances.
If you use modern high efficiency 'phones you will not need much signal level for good volume, and hence you can get a good low distortion characteristic from a parallel-feed transformer-coupled 6H30.
As for solid state, 99% of designs seem to wrap an output transistor in the feedback loop of an op-amp. The figures look good on paper, but I've known many folks whine about the sound quality. (But I'm obviously generalising here).
At the moment I think one sensible approach would be to buy one of the new S c h i i t Asgard amps (about $250 in North America, but will be more by the time they reach our shores), and then modify it with an external mains transformer, a decent volume control, and more ventilation holes. (Just a shame about the adolescent 'look at me, look at me' company name. Oh well).
As for solid state DIY builds, there sure is plenty to dig into on this forum via the search facilities, and also consider the neat open-loop Cavalli-Kan Kumisa 3, which is detailed here: The Cavalli-Kan Kumisa III Stereo Headphone Amplifier.
Good luck
Last edited:
Hello nicoch46 and All,
Applause to the material in the link above. Many power amplifiers have way too much gain. Output tubes with low rp with low gain should see more frequent application.
I am using an Aikido Cathode Follower, high input Z low output Z, with a gain of near 1 (a buffer) to drive a triode connected 6BQ6GTB. The 6BQ6GTB has an rp near 600 ohms which is 1/3 or less than many typical SET output tubes. That means 3 times the damping factor.
Another way of looking at it is the higher the output Z the closer the amplifier is to a current source amplifier. The lower the output Z the closer the amplifier is to a voltage source.
A couple of versions of the power formula taken from the rib of ohms law.
A Watts = I^2 * R (current source amplifier) R is headphone impedance.
B Watts = E^2 / R (voltage source amplifier)
A, above pretty much explains the boomy or flabby bass for headphones with any kind of impedance peak when driven by a high output Z amplifier. The higher the headphone impedance at the resonance point the more watts are produced.
The opposite is true for the voltage source amplifier.
DT
All Just For Fun!
Applause to the material in the link above. Many power amplifiers have way too much gain. Output tubes with low rp with low gain should see more frequent application.
I am using an Aikido Cathode Follower, high input Z low output Z, with a gain of near 1 (a buffer) to drive a triode connected 6BQ6GTB. The 6BQ6GTB has an rp near 600 ohms which is 1/3 or less than many typical SET output tubes. That means 3 times the damping factor.
Another way of looking at it is the higher the output Z the closer the amplifier is to a current source amplifier. The lower the output Z the closer the amplifier is to a voltage source.
A couple of versions of the power formula taken from the rib of ohms law.
A Watts = I^2 * R (current source amplifier) R is headphone impedance.
B Watts = E^2 / R (voltage source amplifier)
A, above pretty much explains the boomy or flabby bass for headphones with any kind of impedance peak when driven by a high output Z amplifier. The higher the headphone impedance at the resonance point the more watts are produced.
The opposite is true for the voltage source amplifier.
DT
All Just For Fun!
They will if you get them across your ears.
Anyone who willingly puts on a pair of earphones connected to a device with several hundred volts of DC internally (no matter how well constructed), when there is absolutely no necessity to do so, is nuts. This is not a device you would chose to give to a child.
Just THINK for a moment.
w
Hello wakibaki,
Truth be told I am more concerned with micro wave radiation from my cell phone killing me slowly than my head phones.
Everything is bonded to the green wire in the wall (as you call it earthed) in my creations. Where you are 8 hours ahead of me do you have a bare copper or green insulated wire or safety that is grounded or bonded to earth?
Do the psych hospitals in your time zone practice ect? Check out Ect.org
DT
Just For Fun!
Truth be told I am more concerned with micro wave radiation from my cell phone killing me slowly than my head phones.
Everything is bonded to the green wire in the wall (as you call it earthed) in my creations. Where you are 8 hours ahead of me do you have a bare copper or green insulated wire or safety that is grounded or bonded to earth?
Do the psych hospitals in your time zone practice ect? Check out Ect.org
DT
Just For Fun!
Hi DT
Even I am not immune to the attractions of these crude devices. If I were marooned on an alien planet and obliged to rebuild technology from the ground up, doubtless I would employ tubes as a stepping stone in the drive to reconstruct the cellular network, the more quickly to fry the brains of my fellow maroons. Other than this unlikely scenario, and the few other applications such as musical instrument amplifiers, high power and high frequency transmitters et cetera, where there is a genuine advantage to be gained from their use, I can see no good reason to perpetuate this obsolete, inefficient and potentially dangerous technology.
w
ECT, bring it on.
Even I am not immune to the attractions of these crude devices. If I were marooned on an alien planet and obliged to rebuild technology from the ground up, doubtless I would employ tubes as a stepping stone in the drive to reconstruct the cellular network, the more quickly to fry the brains of my fellow maroons. Other than this unlikely scenario, and the few other applications such as musical instrument amplifiers, high power and high frequency transmitters et cetera, where there is a genuine advantage to be gained from their use, I can see no good reason to perpetuate this obsolete, inefficient and potentially dangerous technology.
w
ECT, bring it on.
Member
Joined 2009
Paid Member
Hello wakibaki,
In my mind vacuum tubes keep company with grandfather clocks, sextants and silver gelatin black and white photographs, cool old things to play with and enjoy. In their time they were cutting edge.
My day job is mechanical engineering for hospitals, medical research facilities and chip manufacturing clean rooms. We design and build bloody edge environments. Think of the IGBT controller that controls the 400 horse power 3 phase motor that turns the chiller that keeps the space conditioned to chip manufacturing specifications. Or another visual image when they roll you into the brain operating room with MRI 3D digital mapping for resection of your Glioblastoma think of me.
Tubes are a hobby that lets out my inner ten year that still takes things apart with a hammer.
Now back to the original programming, what is better for headphones (or for that matter 18 inch woofers) current or voltage source amplifiers?
DT
Just For Fun!
In my mind vacuum tubes keep company with grandfather clocks, sextants and silver gelatin black and white photographs, cool old things to play with and enjoy. In their time they were cutting edge.
My day job is mechanical engineering for hospitals, medical research facilities and chip manufacturing clean rooms. We design and build bloody edge environments. Think of the IGBT controller that controls the 400 horse power 3 phase motor that turns the chiller that keeps the space conditioned to chip manufacturing specifications. Or another visual image when they roll you into the brain operating room with MRI 3D digital mapping for resection of your Glioblastoma think of me.
Tubes are a hobby that lets out my inner ten year that still takes things apart with a hammer.
Now back to the original programming, what is better for headphones (or for that matter 18 inch woofers) current or voltage source amplifiers?
DT
Just For Fun!
Hi Wakibaki;
Since the circumference of the earth at the equator is 24,901.55 miles, a spot on the equator rotates at approximately 1037.5646 miles per hour (1037.5646 times 24 equals 24,901.55) (1669.8 km/h).
At the North Pole (90 degrees north) and South Pole (90 degrees south), the speed is effectively zero since that spot rotates once in 24 hours, a very, very slow speed.
To determine the speed at any other latitude, simply multiply the cosine of the degree latitude times the speed of 1037.5646.
It is much safer to live on North, or South Pole!
But...
In addition to the rotational speed of the earth spinning on its axis, the earth is also speeding at about 66,660 miles per hour (107278.87 km/h) in its revolution around the sun once ever 365.2425 days.
...it is insane to live on Earth!
Source: Speed of the Earth
Since the circumference of the earth at the equator is 24,901.55 miles, a spot on the equator rotates at approximately 1037.5646 miles per hour (1037.5646 times 24 equals 24,901.55) (1669.8 km/h).
At the North Pole (90 degrees north) and South Pole (90 degrees south), the speed is effectively zero since that spot rotates once in 24 hours, a very, very slow speed.
To determine the speed at any other latitude, simply multiply the cosine of the degree latitude times the speed of 1037.5646.
It is much safer to live on North, or South Pole!
But...
In addition to the rotational speed of the earth spinning on its axis, the earth is also speeding at about 66,660 miles per hour (107278.87 km/h) in its revolution around the sun once ever 365.2425 days.
...it is insane to live on Earth!
Source: Speed of the Earth
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.