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Electro-Harmonix 12AY7 Tube Microphone Preamp

Member for

21 years 2 months
Anyone use this? How does it compare to the SP VTB-1 or the Brick?

Comments

Member for

16 years 6 months

CoyoteTrax Wed, 07/27/2005 - 06:07
I wish I had more time to work with mine since I got it but I ust haven't. My initial reaction to it though is that it's heads above and beyond what you hear from the VTB-1, so there's no comparison.

It's "thick" and has that pure analog sound that's worth far more than $200. It's very "focused" and super quiet. Smooth, creamy, and handles being overdriven extemely well. The natural tube compression qualities are very comparable to some of the higher dollar gear like the gt brick, if not better.

It's not designed with a 1/4" input, the input is XLR only, but if you put a passive DI in front of it, voila! It's a kick ass DI box. The controls are sturdy but it's a lighter box than you'd expect (power supply is external).

You're definitely getting a full 200V to the plate though and that's what's important.

It's a killer, killer deal. It's amazing on vocals, acoustic guitar and hand percussion. haven't used it as a room mic yet but I noticed it does pickup my room very nicely when tracking acoustic guitar.

Wish I could say more but my day ob has gotten in the way of me having much fun with it yet.

Member for

21 years 2 months

Pro Audio Guest Wed, 07/27/2005 - 13:02
Funny, my day job does the same damn thing.

I picked up a pair of these for a pretty good price. I've only tested on vocals / acoustic & electric guitar, but I like what I hear so far. There's a touch of noise if you crank 'em. Comparing them to my syteks, they don't have as much clean headroom, but have more depth and sound better when driven hard. They don't come up to the level of my speck micpre's, but they cost 1/3 of the price, so I can't complain.

I'll try 'em this weekend on some drum tracks, I've got high hopes for them on kick & snare, and will test em on overheads as well.

Member for

21 years 2 months

Pro Audio Guest Tue, 08/02/2005 - 10:26
Tried it on kick (rode nt2, pad engaged, 8 inches off of outer head) and snare (groove tubes gt44, pad engaged, 45 degree angle pointing up the snare's rim. Nice sound, but the preamps had the clip light coming on, even with gain rolled almost all the way off. The sound wasn't clipped, sounded very nice, smoother than when using my spirit mixer pres.

I was much happier with the kick (I used the pre's rolloff on the kick, which may be counter-intuitive but sounds great) than with the snare (but the snare sound in the room wasn't my favorite either, our drummer has tuning issues).

Didn't get to try them on overheads (I was running short on time and the Specks did a great job with 2 cheap chinese ribbons), but hopefully next time I'll try them that way.

Member for

19 years 4 months

Kurt Foster Tue, 08/02/2005 - 10:45
I saw a blurb in one of the audio mags and it made me very curious. What perked my ears up was the fact they say they have high volts coming from the wall wart. There may be something to this one.

Can someone say how many volts the power supply produces? Not what it gets converted to inside the pre but hwat the wart itself is rated at?

Cheap as it is, I have always kinda liked the EH stuff ... I have a vintage Big Muff, phaser and chorus stomp boxs as well as the reissue delay and modulation boxs and I use them all the time.

Yeah, they are noisey and cheaply built but they do have a unique sound.

Member for

19 years 4 months

Kurt Foster Tue, 08/02/2005 - 13:50
[="http://www.eqmag.com/story.asp?sectioncode=38&storycode=9289"]LINK[/]="http://www.eqmag.co…"]LINK[/]
[[url=http://="http://www.ehx.com/…"]LINK[/]="http://www.ehx.com/…"]LINK[/]

Humbucker Jake wrote: [quote=Kurt Foster]Can someone say how many volts the power supply produces? Not what it gets converted to inside the pre but what the wart itself is rated at?

12 Volts, 1000mA, AC current.
Thanks Jake... so it's feeding 12 volts ac to the unit? On the EHX web site they are saying,
"It uses an actual 200-volt supply instead of the "faked out" 12 or 48 volts you'd get with common models, delivering 50 dbs of gain into a high impedance load, and about 40 dbs of gain into 600 ohms."

but then you say it is a 12 v supply .... :?: :?: :?:

Some day I wish I could wrap my mind around how someone can take 12 volts and turn it into 200 without decreasing the amperage. It also seems to me that 1000mA's isn't really all that much juice in the first place. Am I wrong about that too? If this can really be done, couldn't we could create "free electricity"? What am I missing? I'm serious, not trying to bait an argument ... I would love to be convinced that this could really be done.

It would be fun to check one out anyway ....

Member for

16 years 6 months

CoyoteTrax Tue, 08/02/2005 - 15:11
I'm not at home so I can't verify the verbage on the power supply but that thing is a heavy "mutha..." with a really funky connection at the end so I was under the impression that 200v was actually going into the box.

I mean, if you dropped the preamp itself 3 feet from the top of a rack, something would definitly break on that box...granted. It's light and it's not what I'd call "roadworthy".

But if you dropped the pwr supply 3 feet off the top of a rack it would put a phreakin hole in the world. Know what I mean?

Member for

16 years 7 months

fiddler59 Tue, 08/02/2005 - 20:13
I'll chime in on this one. The plate supply foth tube in the pre amp takes very little current. It is very easy to design a power supply that
will give 12v to the filament and through the use of voltage doubler circuits bump up th 12v dc to 200v to supply the plates of the preamp tube with ample current in reserve. The plaes don't draw much at all.
David blackmon

Member for

19 years 4 months

Kurt Foster Tue, 08/09/2005 - 16:13
fiddler59 wrote: The plate supply foth tube in the pre amp takes very little current. It is very easy to design a power supply that
will give 12v to the filament and through the use of voltage doubler circuits bump up th 12v dc to 200v to supply the plates of the preamp tube with ample current in reserve. The plaes don't draw much at all.
David blackmon

That sounds like it could be right.
I don't know very much about the techenical side of things. I only know what my ears tell me.

But if the answer is so easy and works well, what reasons do other manufacturers of high end mic pres (tube & solid state) have for the added expense of a high voltage power supply?

There's gotta be a reason most of the high end boutique builders don't jump on the cost savings a smaller line lump / wall wart would offer. That's what I'm trying to get my head wrapped around.
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