HeadRoom Desktop Millett Hybrid Amp

I heard it, and I LOVED what I heard, so I buiilt my own. Unfortunatley I have not sat down to compare the two of them, but from my limited memory of what I heard, they had very distinctly similar signatures (as expected). However, IIRC the headroom one sounded slightly brighter and more detailed (ever so slightly), which I contribut to a better power supply.

One thing to be careful - make sure your tube amp will be able to handle the impedance level of your headphones (since you mentioned maybe getting either a Grado or a Senn, you might want to check into tube amps that can handle both low and high impedance headphones).

I'm speaking from experience when I say the Millet's drive the Senns and Grados just fine.

I've had a rather close relationship with the Millett Hybrid in general over the past 8 months. It began with leading the group that tweaked Pete's original DIY PCB and has now culminated with spending a good long time with Headroom's version. I've had one of Headroom's prototypes on loan for a while now and if I can find the time I hope to finish my review of it within a week or so. The quick and dirty version of it - this is one heck of an amplifier. I think that there is a misconception by some in the forums who think this is a low-budget, mid-fi amp. Trust me, I've peaked my head under the hood of this beast and done some extensive listening. What isn't common knowledge is that Headroom's version of this amp is not the same amp that you see many of us DIY'ers building. It'll drive everything from Senn 650s to Grado HF-1s to Ety ER4Ses and make them sing while doing it.

I'll get back to work on my official review ASAP and see if I can't wrap that novel up. In the mean time I hope that gives you a peak into what I think of the amp.

Nate

I believe my Bada PH12 is better than the Millett hybrid. I will send my Bada PH12 for 3 listening days to anyone in the USA who has a Millett if they will send me their Millett for 3 listening days.

http://www6.head-fi.org/forums/showthread.php?t=136296

Anyone near Gainesville or Apopka, Florida is welcome to audition my headphone system.

Agreed -- but you can never be too careful (especially since the OP hinted that he might consider other tube amps)

And for 2 grand don't you think it should be ? But after reading your thread I'm confused about the the price of this Bada amp since another member makes it sound like it could be had for $300 or so.

And just for clarification have you heard Headroom's Millett? Or even a DIY Millett (which is significantly different)? I haven't heard the Bada so I can't even begin to guess what it sounds like but it would appear to be from the same family as the Millett (tube/solid state hybrid) although obviously a much different configuration and implementation. The different type of tube used in each amp will likely make a large difference in sound signature not to mention that Headroom's voltage stage is significantly more complex than the FET stage of the Bada. Also, you've got crossfeed, variable gain and switchable inputs to consider as part of the HR Millett package.

Also, my only personal fear with some of the Chinese import products is the complete lack of available service after the sale. Correct me if I'm wrong but you basically have no one to turn to if something goes wrong, right? I suppose you could ship it back to China but that'd be what, $50 to $100? In comparing the two amps I only feel it's fair to mention factors like these which play at least some sort of tertiary role.

Again, this is just my opinion and certainly no more valuable than anyone elses.

Nate

n_maher,

You say that the Headroom Millet Hybrid and the DIY Millet hybrid are different. Would you please elaborate on those differences?

Sure, I'll try to keep it brief as I go into a much more thorough explanation in my review and also I'm still verifying a couple of things with Headroom so hopefully I won't mis-speak here now.

Headroom's Millett is essentially Pete's originall amp coupled with their Desktop module. What that means is that while the DIY version of the Millett hybrid just uses two buffers to supply the current the Headroom Millett uses a much more complex device (their module) which includes both buffers and opamps. My understanding of this (not perfect I'm sure) is that Headroom's Hybrid has an additional voltage gain stage as a result, which means that the tubes are not the primary amplification or current source in their amp. In the DIY millets the tubes are the voltage gain stage while the buffers are the current source. I hope I got that at least close to correct. I'll fire a couple PM's and see if we can't get some expert opinion on this.

Nate

I was lucky enough to be able to give said prototype a listen for a week or so and I'll agree with Nate... it's a very impressive piece.

I did a lot of comparisons when listening...

My first goal was to see how the HR Millett stacked up to my maxed STEPS-powered DIY Millett w/ BUF634 buffers. I wasn't suprised it sounded different than the DIY Millett, but I was very suprised at the level of refinement it showed. The DIY Millett's highs were much crisper, with better separation and an openness that was very impressive. Bass also struck me as being a step up with the HR Millett... it was tighter with more detail, but without any loss of extension.

I was so impressed with its strengths that I decided to compare it to my STEPS-powered DIY M3. The M3 is generally considered to be a "tubey" sounding solid-state amp, and I had generally considered it to be middle-ground between my smooth (if lacking detail) DIY Millett and the uber-detailed and somewhat analytical PPA v2. Well, here is where I was really suprised, as the HR Millett sounded a lot like the M3. The same warm, full and lush mids, with clear, detailed but not overly-bright highs and great full bass with a good balance of detail and extension. I'd say the solid-state output stage of the HR Millett does wonders for the sound at both ends... it seems to allow for an improvement in the quality of bass and treble without losing any of the warmth of the mids, keeping all the benefits of the tube section.

Now, I've also been lucky enough to have some discrete diamond buffers in the DIY Millett since, and I've got to say that they have done wonders in improving the quality of the bass and treble. The BUF634's just didn't seem to be able to do it justice, and the addition of the discrete diamond buffers seems to have improved the overall sound of the DIY Millett in a way that is not subtle. Unfortunately these came after returning the HR amp to Nate, so no direct comparison was done.

So, if I were to be looking outside the world of DIY for a tube or tube/SS hybrid amp, there are really only two options I'd consider. The Singlepower stuff, and the SLAM in particular are great pieces, and Mikhal is a great guy to talk to. It's a beautiful peice that sounds as good as it looks. The feedback control is nice because it makes the amp more versatile... helps it synergize with different cans, which is a huge plus, so that's on the short list. And the Headroom Millett Hybrid is the other... Tyll's enthusiasm is hard to match and the build quality, look and features of the Millett (and whole Headroom line) are tough to beat. The desktop module helps improve the sound across the board while maintaining the warmth associated with the DIY Millett, and you get a bunch of added features hard to find elsewhere... crossfeed (which I'm not a big fan of), a bias switch for tube-rolling and more importantly the gain switch, which makes it nice to use with different impedence cans.

So, I guess that's all I've got. I don't think you can go wrong with the Headroom stuff... their reputation seems to speak for itself with respect to support and quality, and the amps speak for themselves when it comes to the sound. I doubt you'd be disappointed.

I heard the HeadRoom Millet Hybrid at the NY Meet this past Saturday and I have to say it was one of the very impressive setups I heard at the meet (keep in mind the level of equipment that was present). The Millet was hooked up to a Meridian 588 and it was utterly resolving, open, transparent, and balanced with a touch of tube warmness, but drive and dynamic of an SS unit. Just absolutely jaw dropping.

Tyll allowed me to bring the Millet and the PSU to my station where I hooked it up to my APX/Overture setup to the realization that the same mesmerizing sound I had just heard, while still excellent wasn’t quite at the same stunning level. Obviously the Overture (as much as I love this little unit) was not going to stand up to a $2K CD player. But what this did tell me was that HeadRoom’s Millet was very scalable and was not going to be the bottleneck in any given system. With a top notch source, you would have a tremendous system in your hands.

Hey Oski, I don't mean to threadjack or anything, but did you happen to listen to joelongwood's M^3 (or any M^3) at the meet as well? It seems that many people like to compare the DIY version of the Millett with the M^3.

See the posts at
http://www6.head-fi.org/forums/showthread.php?t=136296

Bada PH12 uses amplification that is single ended Class A with no opamps, and no negative feedback, in the output stage. It has a huge power transformer (3 inches high and 5 inch diameter) and capacitors sufficient for a home speaker amp. It uses 3 6NS7 tubes. You can change the sound dramatically with different tubes - I can set tubes for a rich, lush, liquid tube sound with strong bass and excellent detail and midrange clarity, or I can set tubes for the most natural and realistic sound that I have heard from any type of amplification. At $450 new it is a no brainer. I would confidently match it against anything. As far as buying in China, I have had terrific luck in purchasing 7 components so far.