[Yikes]

If you were searching for your ultimate amplifier for use with your favorite dynamic headphones what features or technical characteristics would you look for? Basically describe your dream amplifier, but not by simply stating an existing make and model.

 

[Uncle Erik]

I'm working on it. Or, rather, gathering parts so I can build it after finishing off a few other projects.

I picked up book of projects from Glass Audio and there's a SET 45 based amp for speakers. Looking it over, I realized that you could reduce it to just one 45 pair for output and substitute in a pair of Sowter output transformers for headphones. Even better, the output transformers have multiple taps for different impedances.

So far, I have the tubes, sockets, some resistors and caps, and the output transformers. I plan to order the interstage transformers from Electra-Print. The power and filament transformers will be Hammond, as will the choke. I was planning to use a stepped attenuator on it, but I've gotten curious about some of the transformer attenuators out there... I might just go all out on this one. I'll also put in a switch and wire it so you can switch the output transformer taps to match the headphones.

Casing will be another big project. I'll make another by hand entirely out of aluminum. I like to pick up offcuts of aircraft aluminum on eBay - maybe I'll look for a nice 1/2" plate for the base, then build on that.

That should just about round out the wish list. I still want a 300B based headphone amp, but I haven't found that many DIY plans for one. Still, a 45 amp and a 2A3 amp are a pretty good representation of DHT tubes.

 

[n_maher]

My ultimate dynamic amp already exists.

 

[Cankin]

how about both dynamic headphone and speaker?

β22 + β24

 

[SR-71Panorama]

tubes, transformers, no opamps, SE & balanced.

 

[The Monkey]

Mine would have a stepped attenuator (at least 60 steps) AND a pot. Would it be possible to make each defeatable?

 

[Aura]

What I've got now is very close to ideal, but there is one just a tad better:

 

[Yikes]

[size=small]A friend of mine is designing a high end headphone amp. He already markets a line of electronics. I'm sure that his unique design technique will result in an absolutely killer amp.[/size]

[size=small]Here is the wish list that I gave him.[/size]

1. [size=small]Both balanced and single ended inputs. (1 XLR and 2 RCA)[/size]

1. [size=small]Truly Balanced headphone output and also single ended outputs.[/size]

1. [size=small]It would also add to the units appeal if it could be used as a preamp.[/size]

1. [size=small]If necessary for best sound either switched z or more than one headphone jack for high and low z[/size]

1. [size=small]Dual chassis/outboard power supply.[/size]

1. [size=small]Either dual volume controls or a balance control.[/size]

1. [size=small]If preamp outputs are offered remote volume should be included.[/size]

[size=small]I was just looking for other feedback that I could forward on to him.[/size]

 

[vcoheda]

tube based.

 

[The Monkey]

4-pin XLR out instead of 3-pin.

 

[Duggeh]

I concur. 4pin is the sensible way forward for all parties. Double 3pin is an archaic hangover from the blockhead days and it serves no useful purpose to continue with it when an easy and superior solution is readily availible and indeed would save the amp makers a buck on each piece made.

An amp that Im working up on paper at the minute will use a 4pin LEMO though because XLR is too big although it'll hardly be apt for the topic of this thread.

 

[dreamwhisper]

2 x 3-pin is a little archaic/silly.
It feels ridiculous to have two ends on a headphone cable.