[Hun7er]

Hi there,
 
I search an builder for an custom headphone amp.
 
I have an precise idea of what you want, but we will see if certains things must be change.
 
I'm located in France and prefer a builder located in Europe.
 
My project will use 300b tube as output.
 
Thanks you

 

[Konstantin690]

Direct Heated Triodes like the 300B are not such a good idea for a headphone amplifier, filament noise/hum is a major issue.

 

[Hun7er]

Yes but is has one the lowest distortion and you can get 7-8 watts to drive difficult headphone.

 

[Tom-s]

I don't know what you call hard to drive.
My AKG 340's are powered well via a Bottlehead Crack amp (+speedball).
It's specifically designed for the Sennheiser HD600-650 series headphone.
Further it's the perfect DIY headphone amp for beginners.
And as far as i know not many headphones are harder to drive.
The amp feeds +- 330mW into 600 Ohms so it handles just about every other headphone with ease.
Only the AKG K1000 needs more than 2-3W @ 600 Ohms?
I don't think you'll be able the get a better sound of the HD650 with any other amp.

 

[Konstantin690]

  Yes but is has one the lowest distortion and you can get 7-8 watts to drive difficult headphone.

 
The 300B (and most DHT tubes) is "famous" for it's (curves) linearity, not low distortion.
There is not such thing as "one of the lowest distortion" in tubes, DHT tubes have high amounts of (dominant) second order harmonic distortion that gives that "tubey" and "pleasant" sound.
If your concern is "low distortion" then stay away from tubes.
 
What headphones do you have that needs 7-8 watts of power?

 

[Hun7er]

They also have low distortion.
The problem is that most amp didn't have the right driver tube. So at the end you "hear" the distortion of the driver not the output.
 
But yes if you want the best performance stay away ! However I prefer a bit more pleasant sound but don't that want that colored sound of the an limited driver.

 

[Konstantin690]

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