I got the Tubalizer as a cheap way to get some experience with Octal tubes in the mix. I know all Octal units will sound different so I don't expect this to represent anything but itself in the end. But what the hell, it cost ~ 110usd delivered (in 4 days!). The Rad Shack wall wart was $20.
 
I have an upgraded MinMax pre to compare it to. I have only a little tube gear experience and to me the Minimax is more on the expansive and open end of the spectrum, and as it is famous for, responds to tube rolling well. It is an obviously very good pre amp.
The Tubalizer has only played for 3 hours, just warmed up, not broken in at all, and has a possibly pos tube. Possibly meaningless as it's too soon to say but...it actually doesn't seem to lack any detail, it is more on the solid presentation end of the spectrum, but still very open, and instruments are spread out well. It has some gravity but is not at all slow or heavy, not at all. You can get inside the music, but it isn't as much of a Lucy In the Skies With Diamonds kind of ride like the MM can be ("atmospheric"). It's more Earthly, but still 3D. Is this a common Octal trait? I need a GOOD 6SL7 tube to see what it is capable of, and several days of break in.
I'll compare the two as I go. Guys, I'll try to give meaningful descriptions/comparisons to aid the audio cause, but you're gonna have to read between the lines as "That's not my area" (as Michael would say).

It is obviously a good, maybe great deal. The hum problem needs to be resolved. Hopefully just a tube.
It may be a great part of ~ $1000 system. Ex: I am using an integrated gainclone ($250 for parts), used Sony 685 cdp ($150) as transport, $350 nos dac, Hawthorne Silver Iris speakers ($325 + $25 wood), and ~ $100 cables, Tubalizer $110. ~ $1300. There's even cheaper components than this that are as good.
So the Tubalizer may end up being in the group of new low cost great gear. Ashok and others will have their own points of view on that soon.

Take care,
Don

Ashok, I did find the same behavior when adjusting the bias control, and I settled about 2/3 to the right. Also I burned mine up and they are sending me a new one. The RS wall wart has seperate input tips that can be inserted either neg or pos, of course RS person nor me knew which. First guess was wrong...It goes positive.
I will try a battery next in hopes of eliminating hum. Obviously not an electrician here, maybe it is board components with usa power that are incompatible?
So I liked the sound with my gainclone. It does soften the sound some, but at the same time gives some atmosphere I liked and congealed the music somewhat too. Maybe if you already have tubes in the mix it is less effective. They did seem to develop it for T amps and could work well with them as you say.
If this doesn't work out I may seek a different tube buffer, or a simple octal pre.
Will be good to hear your experience with a T amp, which one?
Don

No speakers?

Wind Chaser - he said he's trying to keep it simple  

Next, you're going to want him to use cables of some sort to connect everything - and that'll open a whole new can o' worms.....

I know this is slightly off topic(and that i once osted previously on this) but who is going to try their integrated. Seems like the best of both worlds. Id like to but the red wine signature and potential of a channel island integrated
is making me hold back. Of course neither of these options have the tube built in.  I think is a  really ingenious idea, just curious how it sounds.

http://www.autocostruire.com/catalog/product_info.php?cPath=41&products_id=294&osCsid=060f0d3b015b495637563bd385b49267

Hi Guys

My 2c worth on the Tubalizer. I had a stepped attenuator lying around which sounded really very good, and was too expensive to leave doing nothing (it was reviewed in TNT see here: http://www.tnt-audio.com/accessories/stepped_attn_e.html).

So I ordered in a Tubalizer and put the two into an enclosure with the Octal poking out the top. That way everyone knows it's a tube preamp, and it looks pretty cool, despite the cheezy metal box.

Anyway, given the hum problems reported I decided to use a 12v SLA.

Hooked it up for the first time last night, and whoa, this is good. There's more hum than with my Tribute Audio autoformer-based preamp, but even using the 96dB Hempcones, the hum is low enough in the noise floor that it bothers me not.

Havent done direct comparisons yet with the autoformer (which is as good a preamp as I have ever used) but this too is a cracker. Like the Tribute unit, Im happy to play rubbish quality CDs that I had written off as unlistenable with other preamps in the system. So it has that musicality thing going. Briefly, it seems to image brilliantly and is tonally accurate, with the sort of clarity the Tribute offers. Both appear to have the performers there singing and playing in the room just for you.

I had a brief play with the "tuning" screw but it only really sounded right with non-rolled off treble when turned all the way clockwise. I need to check whether the hum is reduced at all other points of the compass, but given it sounds best turned fully clockwise I probably wont worry about this much.

Looking forward to comparing this with my Tribute soon and checking out how it works with other amps. So far just hooked it up to my AKSA 50 Nirvana. Never heard the amp sound so good with these two preamps.

The point of all this? Here is a great buffered passive preamp which costs about half the price of the autoformer-based preamp and gives it a real run for its money.

Thanks Luigi, interesting comments.

Does anyone know what the pot does? Does this starve the tube and increase distortion?

At the price, I should probably just break down and buy one. Then wire it up to a regulated 12V supply and also a battery since I have both laying around.

Thought this was interesting, read the last part of the article where it discusses powering a DAC directly with a battery.

http://diyparadise.com/dacs.html

As promised, last night me and a tubaholic mate got around to comparing the Tribute Audio autoformer preamp with the other "passive" I've slapped together (Acoustic Dimension stepped attenuator plus Tubalizer).

Er, within about a few minutes, we realised there was a winner here. The preamp with the Tubalizer edged out the magnetic volume control, which was a huge surprise given it cost half as much Better clarity, far better staging, improved more real imaging, a more forward presentation. All good. Just as if a tube preamp had been introduced to a solid state system in terms of staging which, of course, it had.

By the by, there is no hum with the Tubalizer when used with a 12v SLA. All the hum we heard previously was power amp generatied. No hum at all with Charlize, a bit with the AKSA50Nirvana, a bit less with another solid state "meta-class A" amp. Interestingly, the AKSA was the best sounding of these three, despite having the most hum. When I say "most hum", this is with 96dB Hempcone speakers and is still only just audible from the listening seat with CD on pause.

And by the by, I was wrong about Monica. I hadn't listened to it much before because I had gain problems with the little Charlize amp. But with the AKSA back in the system there is now sufficient gain and I managed to get good listening levels with Monica (that is to say loud enough to get the Missus to yell at me from the other end of the house). This is a good wee unit, and surpasses the Ah Tjoeb plus upsampler single box player (tubed output stage). As Sam T would have said, there's just more there there. Guess there is something to this NOS thingy afterall.

Luigi

Hi Brassear and other tubalizer users

Im using the Siemens gold pin ECC88s. Tried some cryoed Bugleboys as well but couldn't justify the expense. Just using the standard Sovtek Octal in the Tubalizer.  

I am now considering trying the Tubalizer with Monica, and will also try it as a replacement for the analogue output stage in my CD player. I also intend giving it a lash with the Tribute volume control, though in theory impedance mismatches should not be such a problem with an autoformer volume control. Or am I misinformed here?

Has anyone else tried using a Tubalizer in any of these applications? I am most impressed with it as an impedance matching device when used in concert with a straight passive preamp. It's a very cool and cost effective device. The only downside is that the octal doesn't glow much on 12v!

Luigi