Topic: Church transformer based pre

[Church-Audio]

It's all about the sound, so don't compromise that in any meaningful way for size considerations. IMO

Agreed here, remember Frank Lloyd Wright:  Form following Function.  Size should be secondary to performance...

T

Ok.. I will build it about the same size as the UA-5 preamp..

[twatts (pants are so over-rated...)]

It's all about the sound, so don't compromise that in any meaningful way for size considerations. IMO

Agreed here, remember Frank Lloyd Wright:  Form following Function.  Size should be secondary to performance...

T

Ok.. I will build it about the same size as the UA-5 preamp..

Oh, I don't think we're saying make it XXX in size!  I think you should weigh all your options when building this thing and see how small you can get it.  The UA5 has a lot of functions that may not impact your build, like the whole ADC thing...  That makes me think your unit could be smaller than a UA5... 

Also, I think meters would be nice, but not necessary.  Running with a clip-light, you can see where your pre is clipping and use your recorder gain to make up for it...

T

[Church-Audio]

It's all about the sound, so don't compromise that in any meaningful way for size considerations. IMO

Agreed here, remember Frank Lloyd Wright:  Form following Function.  Size should be secondary to performance...

T

Ok.. I will build it about the same size as the UA-5 preamp..

Oh, I don't think we're saying make it XXX in size!  I think you should weigh all your options when building this thing and see how small you can get it.  The UA5 has a lot of functions that may not impact your build, like the whole ADC thing...  That makes me think your unit could be smaller than a UA5... 

Also, I think meters would be nice, but not necessary.  Running with a clip-light, you can see where your pre is clipping and use your recorder gain to make up for it...

T

I was thinking about the output of the preamp it seems to me some people that are running things like MT'S are having problems with using external preamps. I was thinking about a output level controls as well as input level so that you could "tweak the output down" for what ever your connecting the preamp to. So you can run the preamp hotter with out over driving the input of the recording device. I know this is not an issue for interfacing my preamp with a recording console, but it is an issue for some recorders maybe I could offer that as an option.. I am just thinking out loud here...

[PH]

That's a good idea to use with consumer devices like the MT. But, would the variable output sound worse or better than just running the pre at lower level. In other words, which is preferred? Running the pre low or running it hot and attenuating it afterwards. I would guess the latter, but I don't know shit sometimes.

[tenesejedd]

It's all about the sound, so don't compromise that in any meaningful way for size considerations. IMO

Agreed here, remember Frank Lloyd Wright:  Form following Function.  Size should be secondary to performance...

T

Ok.. I will build it about the same size as the UA-5 preamp..

Oh, I don't think we're saying make it XXX in size!  I think you should weigh all your options when building this thing and see how small you can get it.  The UA5 has a lot of functions that may not impact your build, like the whole ADC thing...  That makes me think your unit could be smaller than a UA5... 

Also, I think meters would be nice, but not necessary.  Running with a clip-light, you can see where your pre is clipping and use your recorder gain to make up for it...

T

agreed.... personally, I think the size of the UA-5 is alittle too big. If you can make a nice sounding pre with some basic accessories (clip light, output gain, etc) and have it be the size of the sonosax sx-m2 or the psp-2 for 5 hundo, i would be all over it.  Just my personal feedback. otherwise, i'm really excited to see what you come up with.

[Church-Audio]

That's a good idea to use with consumer devices like the MT. But, would the variable output sound worse or better than just running the pre at lower level. In other words, which is preferred? Running the pre low or running it hot and attenuating it afterwards. I would guess the latter, but I don't know shit sometimes.

edit: meant latter

Well my way of thinking is this. Get all the "good gain" you can out of the preamp and reduce the need for gain in your recording device as much as possible because that is where sacrifices for size vrs noise floor are made. Because I can make a preamp much bigger then a small recording device, and with much less self noise then a wide open recording device. With out much effort. As I am sure anyone here who is into electronics could do as well.. Its not hard to make a quiet preamp when you don't have to shrink it down into a cigarette pack size device.

[Gizby]

To use a colloquialism the kids are bandying about these days, this thread has me all hot and bothered. Carry on.

[dorrcoq]

Well, this pre-amp talk is all fine and dandy, but what I really want to know, Chris, is how brave was your mother?

[Church-Audio]

Well, this pre-amp talk is all fine and dandy, but what I really want to know, Chris, is how brave was your mother?

She was not so much brave as unaware of the fact that these things might blow up when plugged in. After the first few sparks she quit plugging things in for me. So I had to actually start fixing them. Unfortunately it was many years later until I discovered the joys of the Variac. ( transformer for reducing voltage ) thus reducing sparks

[joekar]

Ok guys....I hear a lot of talkin' but I don't smell any solder burnin'..........Summer is approaching......and we will need pre-amps.....get to work.......Oh yeah, hey Chris try to make it no bigger than a jelly bean for Jedi applications.....



Just kidding....Good Luck on the design Chris.....T+

And a big  to nashphil on the GRAMMY.......T+

Peace,
jk

[Nick's Picks]

I'll share an idea out of my DIY preamp dreams.

to save even more on space, why not just have a breakout cable w/XLRf on them. 
so instead of soldering a jack in there w/some wires to connect to whatever..., just run mic cable direct from "whatever" inside the box.  now you just have a skinny cable coming out w/the jacks on the outside.  Instead of pannel mount, they'll just be straight up xlr.

[stirinthesauce]

My apologies to everyone for making my intentions of this thread unclear from the beginning.  

What I really wanted out of this thread is for Chris to explain his ideas for this pre and the thought process involved in his decisions.  A thread for other designers to offer input for questions that Chris may have in his design.  I'm sure everyone on this board has an idea what they want in an ideal pre and what bells and whistles would be nice (myself included) and I think we may clutter this thread with too many opinions and the practical knowledge gets lost in all the opinions.  

I guess someone could start a seperate thread along the lines of "the ideal pre" and offer opinions there.  Just a suggestion though.

Thanks everyone    and thanks to Chris for being kind enough to discuss his design with us.


To add:  I'm not picking on anyone, hell I even offered my opinion earlier    I would just like the more tech savy/homebuilders to share knowledge and us non tech savy (myself) to sit back and learn.

[rowjimmy]

Well I appreciate the clarified intent of the thread but, after reading the whole thing, I can't help but echo a couple of things before I sit back and watch...

Meters: I'm generally in favor of them. seems to me that the Pre is the place were you want the finest control of your sound and so, that's where you'll want to measure it, yes?

Inputs: you can't please all the people all the time, of course. Me, I'm all for standard XLR's but, your custom multi-pin y-cable notion intrigues me. I suppose that if you made a cable for to order for each pre, that would work, but, I'd hope you'd publish the pin-out so that  hackers could also make their own down the line (I don't see why you wouldn't.)

Power: yeah, lots of folks carry 9v batts around and 9v would be ideal for them but, if 12v is what it takes, then 12v is what it takes. Still beats all those terrific pre-amps that requires A/C power.

(extra) Inputs: It would be cool to allow a matrix circuit for say, an additional 2 channels line level input. But maybe that'd be best saved for the next box. Get one thing done right before you add to it, right?

Size: let function dictate size within reason. I carry a laptop half the time, who am I to tell someone to make things tiny and lightweight.

Hell, after making all those little stealth-able boxes, your eyes will probably thank you for working on something a little bigger.

[Church-Audio]

I personally like clip lights and have gotten used to using them with the V2. They are exremely accurate.
I agree on XLR. Only one standard for a reason.

I think 9v is a great idea too, makes mating it with an easy lithium solution a breeze for field power.
Something I think could really be a hit with a transformer based pre is possibly an alternate signal path to give you a warmer sound, such as the Neve Portico silk option. Warm or Transparent. I also think a 4 ch pre would be a good option as well.

Good luck, Phil

Hey Phil did you ever work with Terri Clark?  just wondering...

[Church-Audio]

My apologies to everyone for making my intentions of this thread unclear from the beginning.  

What I really wanted out of this thread is for Chris to explain his ideas for this pre and the thought process involved in his decisions.  A thread for other designers to offer input for questions that Chris may have in his design.  I'm sure everyone on this board has an idea what they want in an ideal pre and what bells and whistles would be nice (myself included) and I think we may clutter this thread with too many opinions and the practical knowledge gets lost in all the opinions.  

I guess someone could start a seperate thread along the lines of "the ideal pre" and offer opinions there.  Just a suggestion though.

Thanks everyone    and thanks to Chris for being kind enough to discuss his design with us.


To add:  I'm not picking on anyone, hell I even offered my opinion earlier    I would just like the more tech savy/homebuilders to share knowledge and us non tech savy (myself) to sit back and learn.

I respect what your saying... I actually wanted to build the "preamp" you guys wanted..... Because its no good if its just something I wanted to do, and nobody likes it... So I want INPUT... I am not some big company who dictates designs and just builds what I want. I guess everyone already knows that. I am just someone who likes to tinker around and I like to be able to build what is needed for you guys. Hell I doubt if I will even own one my self I don't own any of the products I make because I don't have time to use them.. And every time I build something for my self I end up selling it anyway lol. So I respect what your saying about this thread but I really do want your input and anyone's input that will make this product better. Here is my outline for the product..

1- Flat frequency response from 20hz to 50k
2- Super low distortion
3- Hi pass filter with switch
4- Clip lights
5- Battery operation ( external??)
6- Size?
7- Cost effective
8- built like a tank
9- Phase switch
10- Mic pad -20 db?
11- 12 Stepped gain control
12- For gain I was thinking about 40db or so being the target but 60 is not impossible I just don't know how practical 60db of gain is for live concert recording..

These are my initial ideas but I am open to suggestions.