Originally Posted by nysulli
tomb, a guestion of preferences for you
i'm sitting on a millet board, along with a few diamond buffer boards, looking to get into a tube amp, but i'm torn between the MH and a SOHA
typical music would be heavy rock/metal, using HF-1's, i like a decent amount of bass, but it doesn't have to shake my head, just needs to let me feel the kick of the bass drum
which would you suggest between the 2, and if the SOHA, suggestions on 2 or 3 tubes that might work well for me would be great
Well, if your option is to abandon the Millett and its boards, I would definitely recommend that you complete the Millett and the DB's. A Millett with DB's is superior - on the level of the clarity of a PIMETA except with a good bass kick.
However - this is greatly dependent on the power supply. The Millett needs at least a TREAD for minimum good bass. Even then, I can get it into clippling on some music. Most likely, a STEPS or upgrading the basic TREAD is needed long-term - maybe double the power caps on the TREAD, etc. If you've followed Cetoole's thread on the Millett Hybrid Max, you'll see that he's done the same thing, but on the board. Proto's are on order, I believe, but we have yet to build one.
The SOHA does not have the ultimate clarity of a Millett w/DB's, and it is somewhat more difficult to put together - the transformer is a major hurdle because you have to mess with power wiring. Frankly, I will never do it the way most do - with a transformer in the case. I prefer the walwart approach, and the Jameco walwart boxes make that pretty easy.
The number of caps, the regulators, and the CCS make the SOHA board rather complicated and easy to make mistakes. The translation from China had some obvious difficulties. After that, the SOHA is much more robust about power from the basic board - there is no lack of bass whatsoever - and I can't say that strongly enough.
The opamp is a stumbling block, but using a quality opamp such as a OPA2107, AD843/845, OPA627, etc., can get you pretty close. (I used to recommend the OPA551 because of its high current, but I've gotten tired of its sound - too slow.) Steinchen is working on DB's, so the SOHA has the potential for leaving the Millett behind.
Recognize that most of these comments are highly dependent on headphones, too. With the Millett, the 12ae6 tubes give high gain suitable for Senn's and high impedance phones. However, a switch to 12fk6's will cut that gain in half, performing very, very well with Grado's. Grado's are problemmatical on the SOHA - the gain is 50% higher than the 12ae6's in the Millett. Adding output resistors (150ohm) can make the SOHA suitable for Grado's, but that reduces impact and starts to affect frequency response. Even so, most of the tubes are powerful enough to overcome it.
All that's a long way around of agreeing with blueworm: "... it would be too bold to say one is better than the other."
Good (great) tubes I've rolled in the SOHA:GE 6680
- really sterling, fluid highs. A wonderfully liquid music tube. It also seems to have a little less gain than other 12AU7's, so it may be a tad better with low impedance phones.GE 5963
- a "solid state" device - shocking in its tightness and control. You can't believe you are listening to a tube with this one. The only reason I don't put it at the top is slightly less capability on the top end (slightly). This depends on the tube apparently, and can vary some. The tight control results in an almost holographic soundstage, when paired with a phone such as the HD580.EI 12AU7 Elite Gold
- There have been some less than outstanding reviews on the steel-pin version of this tube, but I found the gold version to be the best in the bunch of new-production tubes (Electro Harmonix, JJ). Highs are right there with the GE 6680. I need more time with this tube, it may improve on my scale.Sylvania Gold 5814, TungSol 5814, Raytheon CK5814, RCA Command 5814 -
These tubes seem to run cheaper than the 6189's for some reason - you can find them for $5-$7 in many places. Some tube vendors have started marking up the special series, though. These are not JAN's, but military special spec made before the JAN's. They have the original mfr box and are fully branded with the company name and logo. Great bass power is exhibited on all of these with extended highs. As I've stated elsewhere - the highs and imaging are what distinguishes among 12au7's. Even so, the bass seems more powerful on these than most. The reason that these are better is that the highs are really great, too. Probably the Sylvania Gold is the best in this bunch, by a slight margin, followed right behind by the TungSol. BTW, I tried a GE 5-star 5814 and it was bad. It pains me to say that - I'm a real GE fan. It just had very recessed highs.Electro Harmonix 12AU7EH -
This is the fattest 12AU7 I've seen - it almost rolls over the socket like Joe 6-Pak's belly rolling over his belt.
Perhaps the most powerful tube I've rolled - earthquake like bass, but tight. Highs seem OK, but maybe a tad recessed. Imaging is difficult to gauge because of the great power. I need much more time on this tube. It has gotten pretty good reviews, except for perhaps a metallic signature (I like metallic signatures, though). However, most of the time a new tube will really boom before it gets burned in - that maybe what's going on with this one - it just needs a lot more burn-in.JJ ECC82 -
It seems this tube gets used in a SOHA more than any other, by all reports. I don't get the fascination. A decent tube, it simply does nothing outstanding IMHO. Even the bass is bested by the Electro Harmonix, IMHO. Functional, however - if you get a good price, buy it.JAN (PhillipsECG) 6189 and 5814 -
These are a bit better than the GE 5814. I would classify them as functional. They would impress most anyone unless they've heard the others above. Nothing else very outstanding. If you get a great price, go for it - they are OK in that vein. There is very little difference in these and the JJ, it seems to me.National - rebranded 5963 -
This one looked like it may have been an RCA 5963. However, I discovered one way tubes can become horrible microphonic. In inspecting the tube - it looked like the square getter at top was actually bent down so that it was touching the top mica spacer and one of the plates. Sure enough, I put it in and its intolerable. The slightest touch anywhere - even on the table - is picked up and amplified. Unusable.
P.S. No more than $10-$12 was spent for any tube, except for the EI ($14.95?) Most were $8 or less. The GE 5963 is as low as $4 in many places.