[Mikeb]

I have just been listening to my main system which uses two monoblock Graaf GM20 valve amps, these are described as OTL and OCL type amps using four 6C33 output valves per channel with no output transformer or output capacitor in the signal line, they sound marvellous with a very open and detailed sound, particularly in the top end. This set me wondering if there was a suitable OTL amp for driving the AKG K1000 headphones. Does anyone know of a suitable one or if they have tried one?

Regards

 

[Saint_1]

Well the new Zana Deux is an OTL design, and by all accounts a fantastic headphone amp. It's actually a single ended triode OTL (SE/OTL) so, I'm not sure if it can drive the demanding K1000s. Although it does also use those giant 6c33 power tubes -- which gotta have some juice...

Hope that helps!

 

[humanflyz]

The 6C33 tubes in the Zana are not being used to anywhere near their potential, so no, it wouldn't be the most optimal amp for the K1000s.

 

[newneringa]

how about tenor? anyone?

 

[Donald North]

Quote:

Originally Posted by Saint_1 /img/forum/go_quote.gif Well the new Zana Deux is an OTL design, and by all accounts a fantastic headphone amp. It's actually a single ended triode OTL (SE/OTL) so, I'm not sure if it can drive the demanding K1000s. Although it does also use those giant 6c33 power tubes -- which gotta have some juice... Hope that helps!

The Zana Deux is OTL but does have output coupling capacitors.

6moons audio reviews: Eddie Current Zana Deux

I've been listening all afternoon to my new K1000s powered by an Audio Note Kit 1 300B SET and loving it

Donald North

 

[glitch39]

you'd need to rewire your k1000 and provide balanced source - but LD Mk VI is OTL OCL at a nice price. definitely able to drive those cans with ease

 

[Uncle Erik]

Quote:

Originally Posted by Saint_1 /img/forum/go_quote.gif Well the new Zana Deux is an OTL design, and by all accounts a fantastic headphone amp. It's actually a single ended triode OTL (SE/OTL) so, I'm not sure if it can drive the demanding K1000s. Although it does also use those giant 6c33 power tubes -- which gotta have some juice... Hope that helps!

Unfortunately, the Zana doesn't do very well with the K-1000. It'll play, but neither the Zana nor the K-1000 give off the glorious sound each is capable of. The 6C33C tubes are run very conservatively and they don't put out as much power as the K-1000 needs.

Since the K-1000 is designed to be run from an 8W or greater speaker amp, look for an OTL for speakers, not headphones. I don't know if you'd be willing to DIY, but there are some terrific OTLs at Transcendent Sound. The T16 puts out 15W, which would be about perfect for the K-1000. However, any of Rozenblit's designs would do well - he is one of my favorite designers.

You might also want to look into an Atma-Sphere S-30 (new or used) for the K-1000. Atma also makes great OTLs and Karsten's designs are quite good, too.

Of course, you could use your Graaf monoblocks to drive the K-1000, as well.

Also, you can change the K-1000 pigtail to provide for balanced operation. I strongly recommend against rewiring a K-1000. For one, it is a tricky job, one that can melt a voicecoil if you make a small mistake. AKG no longer provides service for the K-1000 and it is my understanding that AKG is out of replacement drivers. It is not worth the risk.