Originally Posted by Mshenay
Thanks Troll, as I've said like a dozen times. The SunRise II not that great. Get out of here with that crap.
OP get your self a cheapo Millet Max Starving Student Amp, one with a gain switch would work really well with low Gain cans, and in a year or so save up for something nicer, like the LD MK IV and a pair of Byer Dt 880 600ohms
In addition, I HAVE heard of people driving Dt 990s out of an Indeed G3 [and trust me that thing shoves some serious Voltage] but as I have told me self many times, if I'm going to get a $300 pair of 600 ohms can, it's worth also getting an equally high quality amp to drive them. Till then my Dr 880 Pro 250's enjoy the Hybrid Tubes!
There is also once again, the Little Dot 1, which should drive low impedance and Middle [250 300 ohm] cans sufficently well. Not sure what Tubes are compitable with both the LD IV and 1+
No offense - I agree with most of what you've been saying. I'm also gratified to see that Currawong threw a penalty flag.
However, this is confusing I know, but ... There is a Millet Hybrid, the latest version referred to as revMH. The revMH version of the Millett Hybrid was designed/developed by Drew Dunn (drewd) and Nate Maher (n_maher - a mod on Head-Fi). The design was originally published in Audio Xpress magazine by Pete Millett - username "pmillett" on Head-Fi. Just an FYI, but he is the current designer of the Apex amps available on TTVJ. Anyway, Colin Toole (cetoole on Head-Fi) went further with the Millett Hybrid design and designed the Millet Hybrid MAX, which was essentially the Millet Hybrid circuit with full-size heat sinks on the PCB, a fully linear-regulated power supply, and a relay-delay on the headphone connection - all on the PCB. Later on, cetoole modified the power supply for greater performance and shrunk the design to fit into the Millet Hybrid MiniMAX, the prototype of which is my avatar above. Finally, he designed the Millett MOSFET-MAX, which was the Millett MAX using MOSFETs biased to very high currents and included a BantamDAC or GrubDAC directly on the PCB with relay switching between inputs.
A few years ago, Pete Millett came out with a design he called the Starving Student. Again, Nate Maher was involved as the first builder besides Pete and their posts formed the beginning of the Starving Student - later referred to as the SSMH, or Starving Student Millett Hybrid. It was a total departure from the Millett Hybrid family mentioned above, in that it used 19J6 tubes with a surplus Cisco switcher power supply of 48VDC. All of the Millett Hybrid family above use strictly low-voltage space-charge tubes: 12AE6, 12FM6, and 12FK6, with a 24-27VDC power supply. The Starving Student's 19J6 tubes have a 19V heater supply and plates that are rated at for at least 200V. So, the similarity is probably closer to the SOHA and its derivatives, in that tubes are used at voltages well below their plate ratings and paired in a hybrid form with a solid state output buffer. In the case of the Starving Student, that output buffer happened to be a pair of MOSFETs biased by the tube heaters - a really ingenious solution that saved parts count and cost. In fact early on, I referred to Pete Millett's Starving Student creation as a Tube CMoy.
At some point, the SSMH became so popular that a Head-Fi user built them and sold them through Whiplash Audio. For a time, the Millet Hybrid MiniMAX was also sold through Whiplash Audio. A short while after that, Dsavitsk (ECP Audio) designed a PCB implementation of the SSMH. These were sold for awhile through Beezar until the supply of 19J6 tubes dried up. I still have quite a time answering e-mails and other questions about whether there will be anymore SSMH PCB kits. Unfortunately, unless there are some 19J6 tubes found in the hundreds somewhere, no - there won't be anymore PCB's, at least based on the original 19J6 tubes.
So anyway, just to be clear -
1. Millett Hybrid
2. Millett Hybrid MAXed
3. Millett Hybrid MiniMAX
4. Millett Hybrid MOSFET-MAX
5. Starving Student Millett Hybrid
Those are all different amps. However, the first 4 are based on low-voltage, space-charge tubes - the 12AE6, 12FM6, and 12FK6. The Starving Student is different from all of them and is based on the 19J6. There are some 12AU7 versions of the Starving Student available, but not as kits and not in the numbers of the original. Part of this is because the 12AU7 may be the most used tube in headphone amps, period, while the 19J6 was never used for anything having to do with headphones, as far as I know. So, it's easy to design/build something a lot more elaborate than a Starving Student with 12AU7 tubes. The 12AU7 is a much more expensive tube, too. One of the biggest selling points - early on - was that the 19J6 was a $2 tube. That all changed as the SSMH got more popular and the supply of 19J6 tubes dried up.
Just a footnote, but there is an amp using the 6J6, the same tube as the 19J6 but with 6V heaters - it's the Dsavitsk/Beezar Torpedo. 6J6 tubes are also $2 tubes, but they number in the tens of thousands at several tube suppliers and are not going to disappear any time soon.
I know that was a mouthful, but maybe it cleared some things up.
P.S. Just a follow-on comment - in my experience I've tested literally thousands of tubes. It is very unlikely - perhaps a handful out of a hundred - where a single, dual-triode tube has both triodes that match. They're almost always different values - sometimes wildly different. That's why you almost always see a tube per channel in most amps. The triodes are tied together in parallel, so that the differing output capabilities of each triode are averaged for each tube. An amp based on one tube is very likely going to always experience some channel imbalance. You can even things out somewhat with an adjustable bias, but the higher-output triode is always going to react more strongly to musical peaks, transients, etc. (IOW, single-tube amps may not be optimum - IMHO.)
Edited by tomb - 8/16/13 at 8:30pm