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Can somebody tell me what they think of this mic? Groove Tubes GT 66?


Groove Tubes GT66 Tube Condenser Microphone


DonnyThompson Sun, 06/12/2016 - 09:11

The short answer is that GT has a solid reputation for building decent quality mics at reasonable, affordable prices.
(From what I can recall, they are actually a subsidiary of Fender - although I can't say for sure if this is still the case).

You may want to consider what type of mic you need, though, as valve ( tube) mics have a very distinctive sound that differs quite a bit from Solid State ( SS) mics.

I'm not implying that tube mics are one-trick ponies; if the mic is built well and sounds good, you can throw all kinds of sources at it with good results - vocals, guitar amps, drums, horns, and even pianos - but ... you will always have "that" tube sound.

In case you aren't aware, tube mics are definitely not known for their "transparency"; there is a certain sonic character to tube mics that is indeed quite often desired, and that works very well, providing a warmth and richness that emanates from the harmonic distortion of the valve... but, just as often, it's a character that doesn't work - in the event that you are looking at capturing certain transients and with finer detail.

Also, the sound of a tube mic can very greatly depending on which tubes you use in them. Some tubes will add only a slight distortion character, others will provide a more dramatic difference, with more "edge".

Last year, I played around with switching out various tube types in an AKG Solid Tube Mic, and the results varied quite a bit - some sounded "okay", others sounded great, but there were a few that simply didn't sound good.

It really all depends on what you plan on using the mic for.

Take the following suggestions for what they're worth, because you didn't mention in your post what results you hope to gain ( no pun intended) from the mic; nor did you mention what mics you already have in your arsenal, so I'll just throw the following thoughts out for your consideration:

If you are looking for an all-round, "general use" mic, you may want to consider an SS Condenser model instead; this will provide more transparency than a valve model, and is often better suited for quick-transient natured sources; like percussion, overhead drum mics, and even vocals, depending on what sound you desire.

Tube models will generally have more warmth and richness ( depending on the model and the tube being used) and will have a tendency to pick up less detail and "esoterica" than an SS condenser.

You may want to consider picking up an SS mic and then adding a tube preamp - this way, you at least have the option of having the "cleaner" sound of an SS mic, along with the "warmer" sound of a tube-driven model.

And, at some point, if you also added a nice dynamic mic (like a Shure SM7 or EV RE20) and a standalone FET ( Field Effect Transistor) mic preamp, ( FET preamps are common in big-name famous consoles, like Neve, SSL, Trident, Focusrite, MCI, Neotek, Audient, etc.; these use transformers ( XFO's) instead of tubes, and XFO's will also have their own distinctive sonic character, depending on what transformers are used ), you would have a whole slew of sonic options - the best of all worlds, so to speak.

On that note, what audio i-o are you currently using? Because the quality of your digital input/converters is going to matter, too...


Davedog Mon, 06/13/2016 - 22:07

The Groove Tubes GT66 is a truly hidden gem of a mic if it is in fact a real Groove Tubes built one. There were several iterations of the GT mics. There are the M-Audio series, the Alesis/GT series and then the GT series a second time with some models and designs outsourced to China which are now the exclusive guitar center Sterling line. All of them were better than just okay with the very first ones built in the USA having a sheen to the sound that was never repeated in subsequent releases. You can tell these by the AM in the model numbers. This GT66 is probably an Alesis/GT joint concern. Probably reasonably priced and certainly better sounding than most at the same price point.

Fender bought them in 2008 I believe and while they still own the IP address, they don't make GT mics any longer.

pcrecord Tue, 06/14/2016 - 11:00

Grome, post: 439140, member: 49884 wrote: I have a shure beta 584 which I have no yet tried

The Beta 58a is a dynamic mic. For starters, it could be a better choice if you record in an untreated room because it has a good ambient rejection
The 66 as many LCD will pickup noise in the room, more reflection from the walls etc..

Do you want it for YOUR voice or for a general mic to record others. See, if it's for your vocal alone, you better go to a store and try many to find the want suited for you.
Vocal are like fingerprints the best mic for one could be the worst for another.

DonnyThompson, post: 439117, member: 46114 wrote: Last year, I played around with switching out various tube types in an AKG Solid Tube Mic, and the results varied quite a bit - some sounded "okay", others sounded great, but there were a few that simply didn't sound good.

Donny, I can't remember, did you go as far as biasing your tube circuit ? Swapping tubes alone may be deceptive of the quality because they don't all behave correctly with the same applied current...

Grome Tue, 06/14/2016 - 11:05

Up for sale is one very lightly used groove tubes GT 66 professional to condenser mic. This Mic was 999.99 plus tax new.

The Groove Tubes GT66 is a tube condenser microphone that employs a large capsule with an ultra-thin 3-micron evaporated gold Mylar diaphragm. Optimized to capture the most definition and detail from all acoustic instruments like piano, drums, and guitars, the ST66 mic's low-noise GT6205M tube in a Class-A triode circuit provides warmth and detail, adding new dimension to vocal and especially instrument recording.

The GT66 uses triode wiring on specially selected pentode tubes to yield low noise and a more realistic dynamic response than their competitors. Its power supply is designed with a load-balancing circuitry that allows cable runs of more than 200 feet with no deviation from optimal performance.

Groove Tubes microphones employ several advanced technologies that separate their large-diaphragm condenser mics from the rest of the pack.

One of the more important advancements is their Disk Resonator system. With it, Groove Tubes is uniquely able to compensate for the 14kHz frequency roll-off that is inherent in large diaphragm mics. As any good audio engineer knows, this deficiency translates to a lack of sparkle from high-frequency sound sources.

Other manufacturers have typically solved this problem by cutting other frequencies and then increasing the entire signal to help even out the frequency range. Unfortunately, this results in increased noise.

Disk Resonator Technology incorporates a brass umbrella that protrudes from the center of the diaphragm in Groove Tubes GT66 microphone. It gently boosts the diaphragm sensitivity to shorter sound waves, allowing it to respond more accurately to those all-important higher frequencies. The result is optimal sensitivity, full frequency response, and a low signal-to-noise ratio.

Another piece of audio wizardry comes in the form of the ultra-thin diaphragm membrane made of Mylar. While most modern condenser diaphragms are 6 to 12 microns in thickness, Groove Tubes in association with 3M, has produced a highly resilient Mylar that measures a mere 3 microns. This allows the ST66 to deliver an extraordinary degree of sensitivity.
Low-noise GT6205M-USA tube
Disk Resonator design extends high-frequencies naturally
Large 1-1/4" all-brass capsule, hand assembled and oven baked for long term, stable operation
Low-noise 7-pin XLR mic cable with Neutrik connectors
Nickel-plated all brass body
Custom-wound nickel core output transformer
Sterling Audio PSM1 power supply
ST-SM4 shock mount

Davedog Tue, 06/14/2016 - 12:59

Okay I'm gonna repeat myself. The GT66 is a nice sounding mic. IT IS NOT FAIRLY NEW. It may be lightly used and in good condition but Groove Tubes has not made mics since around 2008 and probably some time before that due to working contracts with various manufacturers as I already explained. Is it worth $250? Maybe. Is it right for your purpose? Maybe. The description you posted is the sales description from several years back. I'm sure theres a date on it somewhere. This is one of those purchases that you are just going to have to either do it or not. I will say this, the build quality for GT mics was always above average for their price point. So its probably not junk.

*** So I did read the blurb you posted. There are TWO DIFFERENT model numbers being used in this pitch. One is about the GT66 which is a Groove Tubes model, and the other is about an ST66 which is a Guitar Center model based on the GT circuitry and is branded as a Sterling mic which you can regularly buy used for about $250. SO. IS IT A STERLING MIC OR A GROOVE TUBES??? The actual Groove Tubes is the real deal and the Sterling is a budget version using GT's designs.....which is also no longer available....

To add.....The Groove Tubes mic did retail for $999 in 2003. The Sterling for about $399 in 2007. The sales blurb is wrong in so many ways. BEWARE

pcrecord Tue, 06/14/2016 - 13:00

Grome, post: 439208, member: 49884 wrote: mine and other voices.

not a treated room

Glad to know, this will help us help you !! ;)

In an untreated room, many dynamic mics, like the SM58 or Beta58, will give better results offering a cleaner (ambiant noise free) signal. Of course there is a big IF the preamp has enough clean gain. Because most dynamic have a lower output.

So next question, what is the preamp ? ;)

pcrecord Tue, 06/14/2016 - 14:08

So I understand you are using the preamp of your audio interface (yes they are considered as preamps too)
Which one is it? ;)

Many preamp exist but out of any choices, I recommand that your first should be somewhat on the clean side instead of colored.
If we go to what I consider the bottom of pro equipment, I'd suggest the focusrite ISA one. Those are from a classic designed of their legendary focusrite consoles. They are not at all steril and not the more transparent (due to their output transformer adding a bit of mojo) but they certainly are clean and have a ton of noisefree power (up to 80db) It's the perfect match for low output mics and ribbon mics but also excel with condensers etc... I've go eight of them.
you can also investigate on Grace design and Millennia that are more transparent.

BUT.. yes another thing to consider is the converter. If you go with a high end preamp but send it to the computer via a low end audio interface or via an interface that let your signal go throught it's preamp circuit before hitting the converter, than you are wasting it.

I get the feeling that you are just beginning.
Let's project a bit, what would you want to accomplish let's say in the next year ?
You and your friends demo ? Or open a commercial studio ?
What style of music will you produce, Hip hop, pop, rock ??

If you start from scratch you may want to buy a little package like these and let time go by before investing in the big thing

Grome Tue, 06/14/2016 - 14:35

Im trying to build a small recording studio in my basement.
it will be mostly be used byme and my friends and whoever wants to pay to use it in the future.
I may need more than 3 plugs for the preamp as i will be recording voice, piano and guitar/and probably violin and saxophone at the same time.
I think the consensus is get the Groove GT 66($999 macked down to $250)
and from there, get the other requipements.

I aave another mic Shure beta 59A

DonnyThompson Wed, 06/15/2016 - 03:22

Grome, post: 439213, member: 49884 wrote: I may need more than 3 plugs

The correct term is "inputs" or "channels"... specifically, XLR inputs ( for microphones) and 1/4" inputs for instruments; and you won't find a "3 channel" preamp.
With the exception of single channel models, they come in even-numbers: 2 channel, 4 channel, 8 channel, etc.

Grome, post: 439211, member: 49884 wrote: I will be using pro tool however I don;t know if this info is significant

It is not. Your DAW program ( short for Digital Audio Workstation, which is the recording software/platform), regardless of which you use ( Pro Tools, Cubase, Samplitude, Sonar, Studio 1, etc.) will have virtually nothing to do with the preamp/I-O you use, as long as the model is current ( within the last 2 or 3 years) and with supported drivers ( software engine) for your particular computer's OS ( Mac, PC ( Windows 7, 8, 10).

What will matter is the gain of your preamp. Several of the low budget - entry level preamps have lower gain ratings; which won't matter quite as much with a self-powered mic or condenser , but it will matter if you plan on using a lower output dynamic mic in the future - like the Shure SM7B, or a Ribbon mic. Because these mics have lower output ratings, and because they aren't powered models, they'll require more gain in the preamp than condenser mics do; and if your preamp's gain is rated at 58db or lower, you'll need to gain the pre up ( crank the input gain) to maximum levels in order to get a signal strong enough to record. The problem with this in cheaper preamps, is that doing this will frequently result in the electronics noise level of the circuitry to greatly increase as well at the same time.

Davedog, post: 439209, member: 4495 wrote: So I did read the blurb you posted. There are TWO DIFFERENT model numbers being used in this pitch. One is about the GT66 which is a Groove Tubes model, and the other is about an ST66 which is a Guitar Center model based on the GT circuitry and is branded as a Sterling mic which you can regularly buy used for about $250. SO. IS IT A STERLING MIC OR A GROOVE TUBES??? The actual Groove Tubes is the real deal and the Sterling is a budget version using GT's designs.....which is also no longer available....

I can't stress how much you should pay attention to Dave on this one ( or for that matter, on anything he posts, because he's a true pro). As he mentioned, there is a HUGE difference between GT and Sterling mics. I wouldn't go so far as to say that the Sterling is a "bad" mic - it's not terrible - I have one that I picked up at a clearance sale for $50, and it's "okay"... but it's not nearly as nice as the GT66... You generally get what you pay for. I wouldn't rely on the Sterling as my "main" vocal mic.

As a final note, we've had to coax quite a bit of info out of you on this thread, Grome; your posts have lacked a fair amount of information that we've had to "push" you for. I understand you're new at this, and that's okay, we've all been beginners at some point; and we like to help beginners here... this is what separates RO from almost all the other recording forums out there, but please keep in mind that the more info you can provide, the more we can help you, and the quicker we can help you, too.



Grome Wed, 06/15/2016 - 08:46

Since I'm a beginner, sometimes I don't even know what questions and how to ask it. I try to give all the info I can but sometimes I dont know which relevant info I should give .( sorry about that.
I talked to a recording engineer last night and told me the mic is great.
Dave, thanks I will look into that now.
I texted the guy and asked if its a groove tube gt66 and not the st66.

also the sound engineer told me he is using pro tools but will switch to presonus studio 1 pro. Can i get your opinion on this?

DonnyThompson Thu, 06/16/2016 - 04:26

Many engineers have drifted away from Avid ( Pro Tools) over time and have switched to other DAW programs - most of the time it's because a certain DAW program is easier to use, which is particularly important for those who are in the beginner/novice stages. This doesn't mean that PT is a bad program - to the contrary, it's widely used and highly respected.

Others have moved away from PT because they've found other programs that work better for their individual work flow; this would include certain features that fits best for their styles and methods of recording and mixing ... and still others have moved away from certain programs and have decided on alternate DAW's because of the differences in audio integrity.

Personally, I switched from Sonar to Samplitude about 3 years ago; I'd been using Sonar for 15 years or so up to that point, and, it wasn't an easy move for me to make - I made the switch pretty much while kicking and screaming - LOL - but I chose Samplitude largely because of the urging of Chris ( audiokid ) whom I have an immense amount of respect for - I trust his ears implicitly.

I used to be one of those people who were convinced that all DAW's "sound" the same - because in theory, they should all sound the same, because they all "do" the same thing - but, I found out that this isn't necessarily always true...

It didn't take me very long to hear an obvious audible difference between Sonar and Samplitude; using the exact same raw audio files in both programs - and Samplitude was the clear winner for me. The audio in Samp had a clarity that wasn't there in Sonar... I refer to it as "integrity". Sonar seemed to have a "smear" about it, a lack of definition, and it wasn't until I had the chance to compare it with Samp that I heard the differences. And, I can honestly say that the difference between the audio in both programs was not a "placebo" effect, or "power of suggestion"... Truth be told, I didn't want to switch from Sonar; in fact, I was looking for every reason to not switch from Sonar, because I was just so used to working with it for so long - but - I couldn't deny the obvious sonic differences between Samp and Sonar - Samplitude was the clear winner, even though I didn't want it to be. LOL

I attributed this difference in quality to the program coding of the audio engine. And it wasn't just me, either. Several engineer colleagues of mine whom I respect also came to the same conclusion - as I mentioned, Chris was the first that talked to me about it - but other engineers whom I respect, from another forum I belong to, (Paul Russel, Cass Anawaty at Sunbreak Music) - had also switched to Samplitude from other DAW's, and they too came to the same conclusion that I did.

As far as Avid, you're never going to go wrong with Pro Tools - it remains the most popular and widely used DAW in the industry; most major studios use it, and it's certainly a solid and respected DAW - but you have to get to know it - and it's not an easy program to get to know. Its features are deep, and the more a program can do, the more complex it will be, and the longer it will take you to learn it.*

*I will suggest that if you are planning on a career as an engineer, you should probably get to know PT, as it is widely recognized as a "defacto standard" in the studio world. It wouldn't hurt you to get to know it at some point.

But... for now, and for what you've described as wanting to accomplish, you may be better off starting out with a more "basic" program - like S1, or maybe Reason - because they're more than just a little bit easier to get to know, more "user friendly", and, depending on your level of experience with computer based audio, you can get up and running in a quicker amount of time. There's not as much complexity to those programs as Pro Tools seems to present... and not that Pro Tools doesn't have great features - it's a pro program... but for what you are doing, and being that you are a beginner, you may want to start with a more basic program to get you recording and mixing faster, and to get you used to DAW production... without having to deal with a steep learning curve.

And, while I'm personally a big fan and a serious advocate for Samplitude, it too is a very deep program that takes quite a bit of time to get to know - even for experienced engineers who have been working with DAW's for many years.

Keep in mind, though.... even the "best" DAW program out there won't "make" your tracks sound better than they sound at the source... your choice of mics, preamps and converters will play a huge part in the quality of your sound.

And finally, regardless of "which" DAW you do ultimately choose, get to know it - inside and out. Watch as many instructional videos as you can, spend as much time as you can working with it. Learn about its features, record and mix in it as much as you can. The more familiar you are with your production platform, the better your productions will ultimately sound.


Grome Thu, 06/16/2016 - 08:21

Donny, Thanks for the in depth recommendation. I've started learning Protools from youtube and it does seem complicated but even though this is a different area
that I am interested in, I'm an IT guy(coding,database,analyst,games,etc and an android expert-so if u have questions about android, email me personally) and found the videos easy to follow.
THough my friend recommended Studio 1 pro which is easier to learn,as you said. I know that PT is the standard industry but as you said, people are shying away from it bec some apps
might be better in some aspects. I will take a look at Samplitude too for the heck of it.

Thanks again for writing this, It takes time to write this and this is valuable information and I really appreciate your doing this. I really value everyone's opinion and kindness for
a novice like me.

FYI, this all started when i had a voice recital a couple of months ago and after the recital, to my surprise, some people I did not know came up to me and asked if I had a CD, I told my
vocal coach about it and he said we should make one. We are in the process of learning songs right now and as soon as we have enough, we can start recording.
This is just a hobby for me(for now) and I'm doing this just for fun. I talked to a sound engineer and he says he was willing to do he recording,dubbing, mixing
and mastering 12-15 songs for $1150, which I think is not bad, less than $100 per song. anyway, it will take awhile to study 15 songs so I have time to experiment and
decide(I also play the guitar and sing at a friends bar when I have some free time). Also please comment on this- my coach told me I can have a solo recital where
we can record live- is it wide to do this? maybe do this and pick out the versions that good enough and redo the others that are not in a studio???

Anyway, I'm getting the groove GT66 mic for $250 tonight. Will keep studying Studio 1 and maybe Samplitude for now. There is a fair in Fort Wayne, IN this weekend that
I might go to to get some ides and recommendations for preamps, other studio gears and might buy some if they have a sale. I wil keep in mind what everybody
has told me. thanks a lot!

so far, I will be spending $250 for the mike, Ive had the shure mic for quite awhile now. and about $68 for paint and materials for the basement. that's $318. I think
I can have a decent studio for less than $2000 .) I hope.

pcrecord Thu, 06/16/2016 - 08:55

I started with that Idea 20years ago and I'm around 35000$ in now.. ;) (I keep reinvesting the money I earn since it's not my main job...)

The important thing is to have fun while doing it.. Growth will happen by itself.
Learning the craft is the most important thing to begin with and we can learn a lot with just one mic and a small audio interface.