Topic: Small Stealth Preamp?

[corsair]

My point is... U missed the target market. While U might like to think ur products are meant
for production mixing or even for open tapers, most of the folks who will ever buy ur preamps
are doing it for stealth taping....

And for stealth taping applications, the tapers are not aiming for the best mix, but the possible
best mix W/O getting caught.

Think of this ok music is dynamic I am a live front of house sound engineer. I mix some songs at 85 db some rockin tunes I may mix as loud as 115db in the right venue, with the right artist. You have to look at your recorders level control and set it so there is atleast 10 db of head room. A clip light that lights up 2 to 3 db and stays on for one second is not going to help. You need a VU METER NOT A CLIP LIGHT. end of argument it amazes me how some people talk to me like I dont know how to set a %$#@ level, it's what I do for a living, when I am not selling my little mics and preamps. I know what the hell I am talking about. It's one thing to record a show its just a tad bit more complicated to mix it. In the end who do you trust the guy that tapes a few shows or the guy that mixes them for a living?
I don't mean to be offensive but for christ sakes listen to your argument what does a clip light tell you? when the mix is always changing you need to watch a vu meter because by the time the stupid clip light comes on you already have distortion. And chances are your already overloading the recorders input? so why not just watch the $@@@@@ level on the recorder? that is the best way to maximiize the signal to noise ratio with my preamps. Because I take all the stupid shit you dont need and give you what you do need. I have used everything from Neve to Midas to API the best preamps in the world and at the end, I use my ears and a VU meter to tell me where my levels are at not a clip light that comes on way to early in most cases to be usefull. And if you use the argument that you can some how calibrate the clip light so it corrisponds with your vu on your recorder its not true. Yes when the clip light comes on you may be close to clipping but are you really? or is this just an idiot light? I love good gear and good design. But if the clip light is not accurate AND MOST OF THEM ARE NOT. then hey whats the point lets just take a peek at the recorder if you are in doubt, about levels. And my rule of thumb for your recorders input also applies to the mic input of the preamp to avoid distortion you need atleast 10db of headroom for most concerts and I would argue thats not enough some times. So if a clip light is anywhere from 2 db to 10 db before real distortion what does it tell you?


Chris Church
ps i am not having a good day so I am just a tad bit bitchy sorry.



Chris Church

I agree that clip lights rule.

Nothing posted in that sea of text has refuted the usefulness of clip lights while stealthing.  If I am recording into a jb3, I am not pulling that huge thing out of my pocket/shirt/wherever during most stealth shows to try and read those tiny meters.. On the other hand, I can have a pre (or microtrack) in my shirt pocket with the clip LED facing my chest and all I need to do is push the pocket open a bit and glance out of the corner of my eye for the flashing..

It was suggested that the MD or hard disc recorder will overload if the clip light is lit. That may be but it is trivial to work around.  You advance the gain until the light indicates clipping and then back off the gain whatever amount is necessary (from previous testing) to get to the point that is safe with your gear and provides the appropriate safety margin for the circumstances.

[CHURCH-AUDIO]

I hear you. I am working on a f'in clip light as we speak I understand what you guys are saying but, what i am saying is clip lights are not as accurate as looking at the display or just knowing your gear and setting it 10 db below clip from the onset.

Chris Church

My point is... U missed the target market. While U might like to think ur products are meant
for production mixing or even for open tapers, most of the folks who will ever buy ur preamps
are doing it for stealth taping....

And for stealth taping applications, the tapers are not aiming for the best mix, but the possible
best mix W/O getting caught.

Think of this ok music is dynamic I am a live front of house sound engineer. I mix some songs at 85 db some rockin tunes I may mix as loud as 115db in the right venue, with the right artist. You have to look at your recorders level control and set it so there is atleast 10 db of head room. A clip light that lights up 2 to 3 db and stays on for one second is not going to help. You need a VU METER NOT A CLIP LIGHT. end of argument it amazes me how some people talk to me like I dont know how to set a %$#@ level, it's what I do for a living, when I am not selling my little mics and preamps. I know what the hell I am talking about. It's one thing to record a show its just a tad bit more complicated to mix it. In the end who do you trust the guy that tapes a few shows or the guy that mixes them for a living?
I don't mean to be offensive but for christ sakes listen to your argument what does a clip light tell you? when the mix is always changing you need to watch a vu meter because by the time the stupid clip light comes on you already have distortion. And chances are your already overloading the recorders input? so why not just watch the $@@@@@ level on the recorder? that is the best way to maximiize the signal to noise ratio with my preamps. Because I take all the stupid shit you dont need and give you what you do need. I have used everything from Neve to Midas to API the best preamps in the world and at the end, I use my ears and a VU meter to tell me where my levels are at not a clip light that comes on way to early in most cases to be usefull. And if you use the argument that you can some how calibrate the clip light so it corrisponds with your vu on your recorder its not true. Yes when the clip light comes on you may be close to clipping but are you really? or is this just an idiot light? I love good gear and good design. But if the clip light is not accurate AND MOST OF THEM ARE NOT. then hey whats the point lets just take a peek at the recorder if you are in doubt, about levels. And my rule of thumb for your recorders input also applies to the mic input of the preamp to avoid distortion you need atleast 10db of headroom for most concerts and I would argue thats not enough some times. So if a clip light is anywhere from 2 db to 10 db before real distortion what does it tell you?


Chris Church
ps i am not having a good day so I am just a tad bit bitchy sorry.



Chris Church

I agree that clip lights rule.

Nothing posted in that sea of text has refuted the usefulness of clip lights while stealthing.  If I am recording into a jb3, I am not pulling that huge thing out of my pocket/shirt/wherever during most stealth shows to try and read those tiny meters.. On the other hand, I can have a pre (or microtrack) in my shirt pocket with the clip LED facing my chest and all I need to do is push the pocket open a bit and glance out of the corner of my eye for the flashing..

It was suggested that the MD or hard disc recorder will overload if the clip light is lit. That may be but it is trivial to work around.  You advance the gain until the light indicates clipping and then back off the gain whatever amount is necessary (from previous testing) to get to the point that is safe with your gear and provides the appropriate safety margin for the circumstances.

[Brian Skalinder]

when the mix is always changing you need to watch a vu meter because by the time the stupid clip light comes on you already have distortion. And chances are your already overloading the recorders input?

Most single "clip" lights I've seen do not trigger when clipping, they usually light in the -2 to -3 dB range.  So, even if they light up, you're not already overloading the ADC and clipping.  That said...

Think of this ok music is dynamic I am a live front of house sound engineer. I mix some songs at 85 db some rockin tunes I may mix as loud as 115db in the right venue, with the right artist.

For a single artist in a single venue, the absolute dynamics don't change radically over the course of the performance.  Some engineers slowly crank up the volume as they sort out the mix, but I've never experienced anything like a 30 dB absolute gain change.  I have experienced large relative gain changes, e.g. between quieter and louder songs, but never large absolute gain changes across a single artist's set on a given night.  As such, IME it takes a single loud song to get levels set reasonably close.  Which is where the single level indicator comes in...

You have to look at your recorders level control and set it so there is atleast 10 db of head room. A clip light that lights up 2 to 3 db and stays on for one second is not going to help.

It absolutely helps.  At least it's helped me in the past (I have better level meters now).  Once  I encounter that first loud song of the performance, I get my levels largely set for the rest of the performance, with only minor (if any) tweaking involved.  I've  never needed "at least 10 dB of head room" for any single amplified performance.  Unamplified, yes, and in those situations a single level light is woefully insufficient in my experience.

so why not just watch the $@@@@@ level on the recorder?

Some recorders have meters that are even less useful than a single clip indicator.  The JB3, for example.  And as already suggested, sometimes it's not practical to break out the recorder to check it.

You need a VU METER NOT A CLIP LIGHT. end of argument

Is it possible to achieve greater precision in setting levels with a broad level meter range?  Sure.  Is a single level indicator useful?  You bet.  There is no argument, so to speak.  Some people find the single level meter useful.  You, obviously, do not.

The marketplace is speaking right now:  tapers (especially stealthers, to  whom your gear is most appealing) value even a single level meter indicator (in the -2 to -3 dB range) to help set levels.  You, personally, may not find it useful, but your potential customers apparently do.  How you decide to handle that difference of opinion is a business decision for you to make, of course.

Your post beat me to it, Chris.  But I just finished writing thedamn post, so I'm gonna post it anyway. 

[CHURCH-AUDIO]

Hi I agree with alot of the points you make. Except one dynamics in a live show do swing sometimes by 10 db or more in a real concert. Even with the same artist. Not to mention when I mix a show I ask the opening band to leave me some headroom at least 10 db so When my band goes on you know it. I have mixed 1000's of bands over 20 years and measured levels in a show that go from 90 db to 100 db easlly in the same show. So I feel if you have that 10 db + of headroom all the way around your golden I did not say 30db, I dont know where that came from. I am working on some kind of level indicator maybe 3 db with say -20 -10 -0 db indicators. No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Chris Church

when the mix is always changing you need to watch a vu meter because by the time the stupid clip light comes on you already have distortion. And chances are your already overloading the recorders input?

Most single "clip" lights I've seen do not trigger when clipping, they usually light in the -2 to -3 dB range.  So, even if they light up, you're not already overloading the ADC and clipping.  That said...

Think of this ok music is dynamic I am a live front of house sound engineer. I mix some songs at 85 db some rockin tunes I may mix as loud as 115db in the right venue, with the right artist.

For a single artist in a single venue, the absolute dynamics don't change radically over the course of the performance.  Some engineers slowly crank up the volume as they sort out the mix, but I've never experienced anything like a 30 dB absolute gain change.  I have experienced large relative gain changes, e.g. between quieter and louder songs, but never large absolute gain changes across a single artist's set on a given night.  As such, IME it takes a single loud song to get levels set reasonably close.  Which is where the single level indicator comes in...

You have to look at your recorders level control and set it so there is atleast 10 db of head room. A clip light that lights up 2 to 3 db and stays on for one second is not going to help.

It absolutely helps.  At least it's helped me in the past (I have better level meters now).  Once  I encounter that first loud song of the performance, I get my levels largely set for the rest of the performance, with only minor (if any) tweaking involved.  I've  never needed "at least 10 dB of head room" for any single amplified performance.  Unamplified, yes, and in those situations a single level light is woefully insufficient in my experience.

so why not just watch the $@@@@@ level on the recorder?

Some recorders have meters that are even less useful than a single clip indicator.  The JB3, for example.  And as already suggested, sometimes it's not practical to break out the recorder to check it.

You need a VU METER NOT A CLIP LIGHT. end of argument

Is it possible to achieve greater precision in setting levels with a broad level meter range?  Sure.  Is a single level indicator useful?  You bet.  There is no argument, so to speak.  Some people find the single level meter useful.  You, obviously, do not.

The marketplace is speaking right now:  tapers (especially stealthers, to  whom your gear is most appealing) value even a single level meter indicator (in the -2 to -3 dB range) to help set levels.  You, personally, may not find it useful, but your potential customers apparently do.  How you decide to handle that difference of opinion is a business decision for you to make, of course.

Your post beat me to it, Chris.  But I just finished writing thedamn post, so I'm gonna post it anyway. 

[poorlyconditioned]

Hi I agree with alot of the points you make. Except one dynamics in a live show do swing sometimes by 10 db or more in a real concert. Even with the same artist. Not to mention when I mix a show I ask the opening band to leave me some headroom at least 10 db so When my band goes on you know it. I have mixed 1000's of bands over 20 years and measured levels in a show that go from 90 db to 100 db easlly in the same show. So I feel if you have that 10 db + of headroom all the way around your golden I did not say 30db, I dont know where that came from. I am working on some kind of level indicator maybe 3 db with say -20 -10 -0 db indicators. No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Chris Church

Hey, I like the idea of an instantaneous switch to turn the level meter on or off.

I would concur with others about the ease of using a single clip light though.  There are many Edirol UA5 users, myself included, who can use the single "-3dB" LED to adjust the levels.  Just let it flicker a bit and you're right at -3dB peak level.  I prefer to turn it down just till it *stops* flickering, so you're running -6 or -10dB or so.  This reduces ADC distortion in my experience.

Anyway the point is by periodically checking the clip light you can bump the levels down a bit as the show progresses.  You just have to get used to the "dynamics" of the particular piece of gear you're using.

  Richard

[Brian Skalinder]

I did not say 30db, I dont know where that came from.

Just my addled brain, don't mind me.

I am working on some kind of level indicator maybe 3 db with say -20 -10 -0 db indicators. No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I don't stealth much, but that sounds like a cool idea.

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Yup.  Always a balance between price / performance.

[Lil Kim Jong-Il]

No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Chris Church

Adding a VU meter and a switch adds cost and bulk that I don't think these guys are asking for.  I think most would be satisfied by an indicator at -3db with a short hold time so that the user doesn't miss a blink.  Having to press a switch will draw more attention than just glancing down into a pocket.  If you want to get really fancy, use a two color LED and show green when hitting -6db and red at -3db. 

An example of a peak indicator being helpful is the way I run my 722.  It has a full range meter and a peak indicator LED.  The meters are fine but after things are rolling, I monitor just the peak indicator to know when I need to back off the gain a little.  It's more accurate than watching the ballistics of the meter because it's difficult to see the difference between the last 2 LEDs when the level is bouncing.  The peak indicator is more useful and for low profile work it is the easiest way for me to stay off the limit, even though I have a perfectly functional full range meter.

[CHURCH-AUDIO]

I was thinking of a two color led green =-3, red =clip. I think that is the best way, I now have to figure out how to add that circuit with out effecting my preamps sound quality, this is no small task. I just wanted to use a single burr brown opamp not a pair of them, the only way I can see adding it would be to use two op amps, and use one half for audio, the other half for a clip light. Since my circuit is well balanced between left and right it would work. So any smart electronics guys out there want to come up with a good design that does not allow for me to have to use two op amps, I will give them a free 3 wire preamp for the design of the audio indicator!

No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Chris Church

Adding a VU meter and a switch adds cost and bulk that I don't think these guys are asking for.  I think most would be satisfied by an indicator at -3db with a short hold time so that the user doesn't miss a blink.  Having to press a switch will draw more attention than just glancing down into a pocket.  If you want to get really fancy, use a two color LED and show green when hitting -6db and red at -3db. 

An example of a peak indicator being helpful is the way I run my 722.  It has a full range meter and a peak indicator LED.  The meters are fine but after things are rolling, I monitor just the peak indicator to know when I need to back off the gain a little.  It's more accurate than watching the ballistics of the meter because it's difficult to see the difference between the last 2 LEDs when the level is bouncing.  The peak indicator is more useful and for low profile work it is the easiest way for me to stay off the limit, even though I have a perfectly functional full range meter.

[scoper]

Chris, speaking for color blind people everywhere, if you're using two lights, DON'T make them red and green - we won't be able to tell the difference!!

That was my problem with the SVU-1 - they used green, yellow, and red lights, and it was impossible for me to determine which was which. I had to put a rubber band over the -3 lights, so I knew if I saw a gap I'm going over.

One light, it doesn't matter. Two lights, use blue along with anything else.

Thanks!

Scott

[Javier Cinakowski]

This thread is interesting.  FWIW I really like my Church Audio preamp.

[poorlyconditioned]

I was thinking of a two color led green =-3, red =clip. I think that is the best way, I now have to figure out how to add that circuit with out effecting my preamps sound quality, this is no small task. I just wanted to use a single burr brown opamp not a pair of them, the only way I can see adding it would be to use two op amps, and use one half for audio, the other half for a clip light. Since my circuit is well balanced between left and right it would work. So any smart electronics guys out there want to come up with a good design that does not allow for me to have to use two op amps, I will give them a free 3 wire preamp for the design of the audio indicator!

No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Chris Church

Adding a VU meter and a switch adds cost and bulk that I don't think these guys are asking for.  I think most would be satisfied by an indicator at -3db with a short hold time so that the user doesn't miss a blink.  Having to press a switch will draw more attention than just glancing down into a pocket.  If you want to get really fancy, use a two color LED and show green when hitting -6db and red at -3db. 

An example of a peak indicator being helpful is the way I run my 722.  It has a full range meter and a peak indicator LED.  The meters are fine but after things are rolling, I monitor just the peak indicator to know when I need to back off the gain a little.  It's more accurate than watching the ballistics of the meter because it's difficult to see the difference between the last 2 LEDs when the level is bouncing.  The peak indicator is more useful and for low profile work it is the easiest way for me to stay off the limit, even though I have a perfectly functional full range meter.

I vote for a *single* red led.  I just lights at a single place, like -3dB.  Just like the Edirol UA5.  It is mostly off, and if you see it flicker, you back off a bit.

Two notes:
- the 'clip level' has to be adjusted by a small trim pot (eg., a hole in the case, with a screwdriver to the pcb).
    Why?  Well, the clip level depends on what ADC you're driving, eg., NJB3 vs MD etc.  Adjust it once for your
   piece of gear
- the clip circuit could use a few discrete components (transistor, etc).  I've found "Rolls" products have schematics for a lot of their stuff.  Check out their mic preamps.  I think I've seen something with a few discrete components.  That way you can keep your opamps for the signal.

Good luck, and thanks for listening to the (grumpy) tapirs!

  Richard

[CHURCH-AUDIO]

Hi Richard I was thinking why can't I just set the clip light at 1% distortion and leave it at that, so if you see it on you know your atleast at 1%. Or have the trim pot like you say, humm.... that acctually makes more sence.  I will take a look at rolls.

I was thinking of a two color led green =-3, red =clip. I think that is the best way, I now have to figure out how to add that circuit with out effecting my preamps sound quality, this is no small task. I just wanted to use a single burr brown opamp not a pair of them, the only way I can see adding it would be to use two op amps, and use one half for audio, the other half for a clip light. Since my circuit is well balanced between left and right it would work. So any smart electronics guys out there want to come up with a good design that does not allow for me to have to use two op amps, I will give them a free 3 wire preamp for the design of the audio indicator!

No clip light but level indicator on a momentary switch so that the lights are not always on that way you can stealth with out letting people know that your checking levels. What do you think of that idea?

I thank you for your input I do want to please my customers. But at the price point my preamp is at I will have to raise the price to incorperate the level meter.

Chris Church

Adding a VU meter and a switch adds cost and bulk that I don't think these guys are asking for.  I think most would be satisfied by an indicator at -3db with a short hold time so that the user doesn't miss a blink.  Having to press a switch will draw more attention than just glancing down into a pocket.  If you want to get really fancy, use a two color LED and show green when hitting -6db and red at -3db. 

An example of a peak indicator being helpful is the way I run my 722.  It has a full range meter and a peak indicator LED.  The meters are fine but after things are rolling, I monitor just the peak indicator to know when I need to back off the gain a little.  It's more accurate than watching the ballistics of the meter because it's difficult to see the difference between the last 2 LEDs when the level is bouncing.  The peak indicator is more useful and for low profile work it is the easiest way for me to stay off the limit, even though I have a perfectly functional full range meter.

I vote for a *single* red led.  I just lights at a single place, like -3dB.  Just like the Edirol UA5.  It is mostly off, and if you see it flicker, you back off a bit.

Two notes:
- the 'clip level' has to be adjusted by a small trim pot (eg., a hole in the case, with a screwdriver to the pcb).
    Why?  Well, the clip level depends on what ADC you're driving, eg., NJB3 vs MD etc.  Adjust it once for your
   piece of gear
- the clip circuit could use a few discrete components (transistor, etc).  I've found "Rolls" products have schematics for a lot of their stuff.  Check out their mic preamps.  I think I've seen something with a few discrete components.  That way you can keep your opamps for the signal.

Good luck, and thanks for listening to the (grumpy) tapirs!

  Richard

[poorlyconditioned]

Hi Richard I was thinking why can't I just set the clip light at 1% distortion and leave it at that, so if you see it on you know your atleast at 1%. Or have the trim pot like you say, humm.... that acctually makes more sence.  I will take a look at rolls.

You want to trim it at a fixed level, like -3dB.  That way, you just watch the light and adjust your gain so it is just below clipping the ADC.

There are simple discrete circuits that will drive the light.  I don't know if they will respond quickly/reliably though.  From my cursory analysis of the Edirol UA5, the clip light appears to come directly from the ADC somehow (?), and not from the preamp stage.  I don't know how this works though...

  Richard

[scoper]

Church Audio's smallest, cheapest pre-amp is FS in the Yard Sale..

[schoff]

Is it just me or at 4.75" by 9" by 2.5" the Reactive sounds spa-2 doesn`t seem to be that stealthy? 9 inches that`s pretty big and not the type of thing you can easily hide on your person