Hiw good an amp was the original Millet Max that used the BUF634?

The BUF634 Millett was actually just called the "Millett" and not the "Millett Max". I have one that I built and really like it. I also bought two PCBs to build the original Millett Max but never got around to it, but I did hear it once at a meet and thought it was better sounding than the original at driving Grados. I know the BUF634 version sound quality depends somewhat on how good the output coupling caps are... I suspect this is probably true of the Max as well though I honestly can't remember the schematic.

I know the BUF634 version sound quality depends somewhat on how good the output coupling caps are... I suspect this is probably true of the Max as well though I honestly can't remember the schematic.

Yep, this is definitely true of the new Max version as well.

The BUF634 Millett was actually just called the "Millett" and not the "Millett Max". I have one that I built and really like it. I also bought two PCBs to build the original Millett Max but never got around to it, but I did hear it once at a meet and thought it was better sounding than the original at driving Grados. I know the BUF634 version sound quality depends somewhat on how good the output coupling caps are... I suspect this is probably true of the Max as well though I honestly can't remember the schematic.

thank you, thank you .... that told me what I needed to know.

With the hd600, I called mine 'Clipper'... it was a *much* simpler time...

buf634 is not the best thing for driving low impedance headphones.

For mid and high impedance headphones many people consider it a bit

bright.

Ray Samuels SR71 and 2005 versions of headroom product also used buf634.

Tube front end takes a bit of the harshness away.

buf634 is not the best thing for driving low impedance headphones.

For mid and high impedance headphones many people consider it a bit

bright.

Ray Samuels SR71 and 2005 versions of headroom product also used buf634.

Tube front end takes a bit of the harshness away.

Oh, good to know. I have already passed on the amp. Specifically, I wanted the amp for low impedance Grados. But, after a little research I suspected the newer revised Millets would do much better job .... thanks for the confirmation Kevin.

... and 2005 versions of headroom product also used buf634...

No they didn't. They used HA-5002's, which are rather dark, and get more so the lower the impedance as far as I'm aware.

No they didn't. They used HA-5002's, which are rather dark, and get more so the lower the impedance as far as I'm aware.

Oops. You are absolutely correct. There was another major amp out there at the

time that used buf634's. Brain fade.

There were also amps that used stacked buf634's or stacked 5002's. Don't remember the names of those either.

Edited January 31, 200917 yr by kevin gilmore

Oops. You are absolutely correct. There was another major amp out there at the

time that used buf634's. Brain fade.

There were also amps that used stacked buf634's or stacked 5002's. Don't remember the names of those either.

Jan Meier uses stacked BUF634's in his CORDA amps.

I wouldn't call the original Millett with BUF634 bright; it's actually quite neutral (for an amp with relatively high distortion from a single-ended no feedback triode stage). The distortion profile of the amp is so strongly dominated by the tube stage that the buffers are comparatively insignificant. It is a fairly tubey sounding amp and by no means unenjoyable.

The distortion profile of the amp is so strongly dominated by the tube stage that the buffers are comparatively insignificant. It is a fairly tubey sounding amp and by no means unenjoyable.

That is almost exactly what AMB says.

Still, the diamond buffer on the new Max seems to have a lot more ooomph than any of the monolithic buffers. So given a choice, the new Max is a no brainer. Even moreso with the upcoming new PCB version and improved power supply.

.

Even moreso with the upcoming new PCB version and improved power supply.

Which one is that beefy? Do you mean the Mini-MAX ... or something even newer?

That is almost exactly what AMB says.

Still, the diamond buffer on the new Max seems to have a lot more ooomph than any of the monolithic buffers. So given a choice, the new Max is a no brainer. Even moreso with the upcoming new PCB version and improved power supply.

Is it still possible to get in on the order for the upcoming new PCB version? I confess I haven't been paying any attention to the DIY threads on HF (mostly I've been working on finishing a pair of speakers and thinking about what tube power amp to build).

Which one is that beefy? Do you mean the Mini-MAX ... or something even newer?

Something newer - MAX V1.2! It's an update of the previous MAX, incorporating the low-noise power supply improvements from the Mini, as well as relay switched inputs and a place on the board to mount a Bantam DAC and a few other improvements.

There's more info on the MAX DIY forum that shows the proto board as well as TomB's comments on his and Colin's new baby:

DIYForums.org • View topic - ETA on PCB 1.2?

Yep, what they said. The full size board with the power supply improvements from the Mini Max, and provision for a bantam DAC on board.

Optionally to the Bantam, you could just add another set of RCA jacks and use the relay for two external inputs.

Something newer - MAX V1.2! It's an update of the previous MAX, incorporating the low-noise power supply improvements from the Mini, as well as relay switched inputs and a place on the board to mount a Bantam DAC and a few other improvements.

There's more info on the MAX DIY forum that shows the proto board as well as TomB's comments on his and Colin's new baby:

DIYForums.org • View topic - ETA on PCB 1.2?

Nice ....

That's sweet. Thanks for the link. Maybe I'll build one with the BantamDAC for an office rig.

That's sweet. Thanks for the link. Maybe I'll build one with the BantamDAC for an office rig.

I'd recommend a Mini Max and a y1. Well, that is what I did anyway

I'd recommend a Mini Max and a y1. Well, that is what I did anyway

The y1 looks sweet; thanks. It's so hard to keep up with the various DIY projects that are available. Do you know of any DIY DACs that use the Burr-Brown SRC4392 to reduce jitter? That's the part I'd really lust after.