New DIY'er & a Nice Tube Mic-Pre (G9?)

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

XaiuM

Member
Joined
Jun 8, 2004
Messages
17
Location
St. Louis, MO
Hello, I'm glad that I found such a wonderful forum for DIY audio things. I'm just starting to get into the world of recording, and am currently working on a 3-tube guitar tube amp.

I'd like to begin work on a very good sounding tube mic-pre. I have tentatively decided on the G9, but without any real knowledge pertaining to the sound quality. All I've read is a few paragraphs saying it was good. Quality components aside (I do what I can), how does it compare to modern 2000 dollar tube mic pre's? I like the fact that I built what I'm using, although the money saved certainly does help. The complexity really shouldn't be an issue, as I am only 17 but my dad has about 30 years experience with electronics and tubes. If you get me started, I'll probably end up detailing my build with pictures or something, I'm pretty computer-savy. So if ya got any suggestions, lemme hear them!
 
Hi XaiuM,

Welcome to TechTalk!

I may be biased in this question, but I'll give it a shot:

For a good-sounding, versatile, relatively-easy-to-DIY and well-documented tube mic pre, I don't thing you'll find any competitor to the G9.

As for sound quality, let's just say that a tech - with known good ears - sold his D.W.Fearn a couple of days after borrowing the prototype G9

Only drawback is that you don't have extreme amounts of gain - so you could run into problems with quiet ribbon-mikes on soft sound sources. I think it has around 60dB gain in the OEP-version.



Jakob E.
 
[quote author="gyraf"]Hi XaiuM,
Only drawback is that you don't have extreme amounts of gain - so you could run into problems with quiet ribbon-mikes on soft sound sources. I think it has around 60dB gain in the OEP-version.
[/quote]

Is it better gain with the Lundahl's?

Robert
 
how does it compare to modern 2000 dollar tube mic pre's?

IMO my G9 is up there with the very best of them. I think 2000 would be the on the lower side of what you could expect to pay for two channels of something comperable. Of course the quality will depend on your choice of components to some degree...

The gain could be a problem depending on what you record. I have a friend taking it on classical recordings and that's always his complaint, but for some reason he keeps using it and doesnt give it back :grin:

Good luck!

Michael
 
Gain shouldn't really be a problem because the mic on this pre would probably be micing either a drumset or a 4x12 marshall cab, either way it shouldn't need a ton of gain. Just wondering, how much are we looking at for quality components on the build? I have access to quite a supply of parts, but maybe a general estimate?
 
I am also quite new to these things, so:

1. Can anyone help to define the caps that I should spend money on?

2. Anyone with parts lists for UK / Europe?

This will probably be my next project, I already have the PCB, so any help or tips deeply appreciated!

Robert
 
I'll chime in and say that my G9 gets a lot of use. It has a very nice 'round' bottom end that is awesome for bass guitar, though I've also used it for acoustic and vox to good effect. In fact, every single thing I've put through the G9 has sounded good.

Ric
 
only thing to bear in mind is to make sure to add up all of your costs before taking the plunge. Trannys get $$$ after awhile... so do the math before committing :)

the pre is definately a winner though!
 
[quote author="gyraf"]
As for sound quality, let's just say that a tech - with known good ears - sold his D.W.Fearn a couple of days after borrowing the prototype G9

Jakob E.[/quote]

C´mon Jakob..if that "tech" had good ears..he/she wouldn´t have invested in the D.W.F in the first place.. :razz:

Kind regards

Peter

P.S..just joooooking..;-)
 
I've had a G9 in my studio for about 2 weeks now & it is absolutely fantastic. I built the first one for our music studio, & the engineer there loved it too. So much so, that I had to build a second one for myself, he would not let go of it.

The first one had OEP output transformers, one chan OEP input tranny & the other chan had a Lundahl input tranny. The general consensus is that the OEP input sounds nicer & fatter than the Lundahl. My unit has OEP's all round & I am very happy with it.

I changed from a half Neve mic pre (input section Neve only, SS balanced output) & the sound has improved hugely. Tight bass end & plenty of that "back of the throat" silkiness. Beautiful.

Peter
 
[quote author="peterc"]I've had a G9 in my studio for about 2 weeks now & it is absolutely fantastic. I built the first one for our music studio, & the engineer there loved it too. So much so, that I had to build a second one for myself, he would not let go of it.

The first one had OEP output transformers, one chan OEP input tranny & the other chan had a Lundahl input tranny. The general consensus is that the OEP input sounds nicer & fatter than the Lundahl. My unit has OEP's all round & I am very happy with it.

I changed from a half Neve mic pre (input section Neve only, SS balanced output) & the sound has improved hugely. Tight bass end & plenty of that "back of the throat" silkiness. Beautiful.

Peter[/quote]

Didn't quite understand this post, were you saying that you liked the G9 better than the Neve and changed your favorite mic pre preference? Or did you just change the subject and added to the discussion how much you like your front end Neve pre with modified output.
 
I think he changed from NEVE to G9...

Anyway. One could get more gain if not using the output transformer. If you are runing it into an AD converter, or any other modern gear with 10k+ input impedance, you can use a impedance balanced circuit and feed it directly from the cap. Then you will have 6db more gain, and that´s 66dB total.

I usually find that 60dB is enought with my ribbon mics.
 
Is this a pre I can use for every track without running into problems easily? What is the frequency curve like?

Thanks,
 
the frequency curve is FLAT i reckon and yes you can use this pre on every track, dunno why you shouldn't? this practice of using different pres is a new thing
 
Just thinking it was maybe like the UA 610 which I've heard might not be the greatest as one's only pre. That might be wrong though. So you think frequency build-up when using the same pre doesn't happen as easily as is said? That makes sense to me unless you're miking an acoustic guitar for example, using the same colored pre, same mic and mic position in several tracks.[/u]
 
sorry, i did not know where else to post, and this seemed as good a place as any!!

last sunday, 27 august 2006, morning, hangover, internet to ease my thought passages, i stumble on the gyraf website, from there to here, from here to audio kitchens resulting in two sets of pcbs coming through the post yesterday!!

i built my son a 15w class a amp 18 months ago that i need to rewire :mad: so need a project for my studio, i had to post as i have never been so excited as i am now!! two sets of g9's for the studio, and thats just a start.

ha, ha, life is good!!

you will see my posts all arround this forum as i aint the most clued up on electrics in the uk, or even bolton, infact probubally my house!!

i had to post as my wife does not understand why i've not stoped grinning for 5 days now :green: and this seemed to be old enough not to be deemed a thread hyjack.

any good uk suppliers out there?

Iain
:green: :green: :green: :green: :green: :green: :green: :green: :green: :green:
 

Latest posts

Back
Top