All things Green Pre

[fucanay]

[quote author="dissonantstring"]happy tom...look here.
http://www.wunderaudio.com/PEQ1product.html
a $400 green pre only bested by a $2.3K wunder audio pre? :green:[/quote]

Actually, I think they came out to about $150 per channel for me. And to think that the 1073, which runs about $4k, didn't hold up as well. It's pretty crazy. The Green had similar mids to the Wunder, but the 1073 lacked that. The Green had considerably less bottom end than both of the others, but the 1073 wasn't very defined and what the Green had was pretty defined.

It makes my think that maybe we could mod the green to have output trannys and have the best deal on preamps ever.

Matt

 

[dissonantstring]

hey matt,
i was thinking the same thing. i wunder razz what w*ndr audio is using for transformers.
-grant

edit: w*ndr site says 80% nickel, 15% iron and 4% cobalt. (the extra 1% is magical mu-metal - i guess) made in UK.

 

[Greg]

Not to say the Green Pre isn't a good preamp, but honestly I think your test was kind of biased. Usually, the last thing I grab when recording acoustic guitars is a Neve, for the exact reason you mentioned... murky. I think your test was limited to come up with definitive conclusions on whether or not the Green can holds its own against a Neve or the Wunder. I don't know if it can since I don't own one, but the point I'm trying to make is I would have done more testing (kick drum, snare, bass, guitars, vocals) before coming to a conclusion. Also, whether or not the acoustic was by itself or in a mix also makes a huge difference.

Trust me, I'm not knocking the Green... just trying to point out that the test could have been more extensive before posting conclusions.

Enjoy the Green !!!

 

[fucanay]

[quote author="Greg"]Not to say the Green Pre isn't a good preamp, but honestly I think your test was kind of biased. Usually, the last thing I grab when recording acoustic guitars is a Neve, for the exact reason you mentioned... murky. I think your test was limited to come up with definitive conclusions on whether or not the Green can holds its own against a Neve or the Wunder. I don't know if it can since I don't own one, but the point I'm trying to make is I would have done more testing (kick drum, snare, bass, guitars, vocals) before coming to a conclusion. Also, whether or not the acoustic was by itself or in a mix also makes a huge difference.

Trust me, I'm not knocking the Green... just trying to point out that the test could have been more extensive before posting conclusions.

Enjoy the Green !!![/quote]

Absolutely Correct. The only conclusion drawn was that this is a really great preamp, especially for the price. We didn't try to compare on all sources because we were just goofing off and having fun. It started as a comparison between the Neve and the Wunder and we tried the Green as an afterthought, since I had brought it with me.

It was not my intension to pick a source that would make the Green better, it just happened to be what we had set up. But regardless of that, the Green "did" hold it's own in the test I described above. All three on acoustic guitar. Take from that what you will.

Matt

 

[dissonantstring]

hmm,
i see greg's point, but i took matt's review for what it was and didn't take it as a diffinative conclusion to anything (sorry greg, no offense intended). of course we all would use different mics , pres and dynamic processors for different sources, sounds and tracking compliments so nothing is conclusive no matter what. but matt did use his ears and described what he heard. thanks for that matt. sorry to be so OT.
regards,
grant

 

[clintrubber]

Never heard of Wunder before. Nice looks, that pre !

And not to nitpick, but I guess it's best of both worlds.
I mean: they say they're not a Neve-clone, no, but don't want to miss the opportunity to attract people with their Neve-esque look....
OK, we've seen that before (in a somewhat different segment of the market...)

end of rant - happy pre-amping :thumb:

 

[Jonkan]

Im having some problems with my green pres when connected to unbalanced inputs.
I wrote about it in a different thread, but i realised it might be better if i asked the question in this more appropriate thread.

I can only wire them one way, or they start acting like a passive mixer... All the signals are summed to all outputs when connected to my soundcard.

This is the only way that works, but it is a bit noisy from the computers PSU:

green pre end xlr out: pin1=shield, pin2 pin3 connected as usual.

Soundcard end TR jack: tip=hot, sleeve= ground and neutral connected.

If ground was lifted in either end, i got the above mentioned problem.

So i cant lift ground to get rid of noise, so what other options do i have?

Any ideas?
/Jonas

 

[peterc]

Try this :

Pre out pin1 to card Gnd,
pre out Pin 2 to card hot,
& leave the pre out pin 3 unconnected.

Peter

 

[Jonkan]

ok, that was probably the only way i hadnt tried already. I will try it and report back!

Btw, these pres sound incredible. I have only recorded some electric guitar, and some toms as of now, but i have gotten some very good sounds out of these pres.

/J

 

[enthalpystudios]

what should I do if I want to take out my output pots? Does that require a 10k resistor and a jumper? Or can it just be left out?

Just don't have any room on my panel, it would screw up all my holes/knobs and placement. Besides, I probably won't ever use it much.

Thanks

billy

 

[peterc]

Just link the 2 holes of the pot that are closest to the toggle switches.

Peter

 

[Yoannv]

Hi all,
I have now finish the four boards of my Quad Green pre, and they all seem to work well !
But it remains a "small" problem, that is a consequence of a little mod I have tried.

I decided to add a LED to show if 48v is active, or not.

So, I took the leg of the 48v switch, solder it to a resistor (15k 1W), solder that resistor to the LED (+), then, wire the other leg (-) of the LED to the ground point in the Led-Meter section.

It seems to works fine, when just one pre give phantom power.
But, if I active 48v on an other board, I get hum on all the pres !

I spend a lot of time to try to understand where I am wrong. If I take off the LEDs, everything works fine.

In my research, I discover that my ground connection doesn't follow perfectly Rane recommendation, I use star ground for all ground connection, and it seems OK, but why this Led mess up everything ?

An idea ?

a+
Yoann

 

[peterc]

Yoann

Turn on all the Phantoms with LED's & check the voltage before & after the 48v reg. Check that there is greater then 52v before the reg. Might be stressing the mains transformer to the point of hum.

Peter

 

[enthalpystudios]

thats just what I did right after I posted peter, good to know I figured correct. Also, which pin of the lm339 is the buffered input signal? and where does the rectification take place? I can't quite get that far with my silly hack knowledge. Just trying to find a good pin to tie these little VU's onto rather than the led's. I think I may leave the lm339 off, and use the led holes to wire in some led's for illumination. just have to find a good place to wire the vu... It doesnt really need to be super accurate either.

anyway, hopefully I'll have some pics up later on this evening, it's almost done! finally! just need to clearcoat the frontpanel and assemble. I can tie in the meters whenver.

billy

 

[DaxLiniere]

How much would the quality of the BC550B transistors affect the quality/linearity of the mic preamp?

I don't understand the function of these transistors, so I can't decide for myself.

I just replaced the Fairchild BC550 with unknown (but supposedly name brand) BC550B transistors.

Fairchilds were $0.15 from RS
unknowns have a silver face & were $0.26 from local electronics 'corner-shop'.

The gain increased by 0.4dB, but noise floor is still -46dB at 66dB gain

Any suggestions appreciated!
Thanks guys!

 

[Yoannv]

Turn on all the Phantoms with LED's & check the voltage before & after the 48v reg. Check that there is greater then 52v before the reg. Might be stressing the mains transformer to the point of hum.

With all LEDs on, but nothing plug on XLR IN, I have about 47v before the reg (LM317).
If I plug something on XLR in (static microphone), it's lower.

So, my transformer (30VA) can't give enough ?

Should I let done this LEDs ?

Thanks for help.
:guinness: :sam:

a+
yoann

 

[peterc]

Yoann

What is the voltage before the 48v reg with no Phantom power turned on? It might be that you would need an extra diode m& cap in the phantom secton to get the voltage up higher before the reg.

Peter

 

[Yoannv]

What is the voltage before the 48v reg with no Phantom power turned on?

With no phantom power, I have 59v...
I didn't thought this LEDs could take so much...

Do you still think I can solve it with a diode and a cap ?

Thanks again, Peter.

Yoann

 

[peterc]

Do you still think I can solve it with a diode and a cap ?

No, that would push the voltage to nearly 90v, too high.

Does the voltage to the +15 & -15v supplies also go down a lot when switching on more than 1 phantom supply?

Peter

 

[Flatpicker]

[quote author="DaxLiniere"]...but noise floor is still -46dB at 66dB gain[/quote]
How are you measuring the S/N ratio? Has anyone else ever measured it?