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  #1  
Old 08-21-2007, 02:55 PM
konbit konbit is offline
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How to work a rotary mixer

Any comments on this thread and its various pronouncements?

http://deephousepage.com/forums/showthread.php?t=142204
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  #2  
Old 08-21-2007, 03:09 PM
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As I understand it, it is supposedly technically more proper to cut the amps' input sensitivity back and use the mixer with inputs/outputs at Unity

better signal to noise ratio is what i have read...

practically speaking, I normally run my system with the amps wide open and the mixer's master output pot pretty low, channel faders around 7 or so....
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  #3  
Old 08-21-2007, 03:39 PM
clubman5 clubman5 is offline
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According to both Crown and Bryston, you get the best s/n ratio running your amps input attenuators as high as possible. Preferably wide open if you can.

QSC states that the markings of the face of their amps are actual indicators of the amount of gain, and you use the input level controls on the amps to balance out to your desired level.

I am of the opinion amps input level controls wide open sounds the best, cut back at the mixer, and the crossover output level adjustments.

Others feel its better to use the amplifiers input attenuators. Of course, sometimes you may have a situation where you have no choice other than to use the amps input level controls.

You have to play around with your system, and see what you hear, if you hear a difference either way, and what, if anything, you prefer.

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  #4  
Old 08-21-2007, 04:08 PM
konbit konbit is offline
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Quote:
Originally Posted by clubman5
According to both Crown and Bryston, you get the best s/n ratio running your amps input attenuators as high as possible. Preferably wide open if you can.

QSC states that the markings of the face of their amps are actual indicators of the amount of gain, and you use the input level controls on the amps to balance out to your desired level.

I am of the opinion amps input level controls wide open sounds the best, cut back at the mixer, and the crossover output level adjustments.

Others feel its better to use the amplifiers input attenuators. Of course, sometimes you may have a situation where you have no choice other than to use the amps input level controls.

You have to play around with your system, and see what you hear, if you hear a difference either way, and what, if anything, you prefer.


But how about master out and channel pots? Does it really make any difference, sonically, if you are running your master at 5 and your channels at 9 versus your master at 9 and your channels at 5?
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  #5  
Old 08-21-2007, 04:30 PM
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Quote:
Originally Posted by clubman5
According to both Crown and Bryston, you get the best s/n ratio running your amps input attenuators as high as possible. Preferably wide open if you can.


good to know!

Thanks!
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  #6  
Old 08-21-2007, 09:17 PM
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A hotter source signal should result in lower noise being picked up in the cables
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  #7  
Old 08-22-2007, 01:07 AM
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About the amps, I learn that amps should go Full, Input and Channel Pots too, Its an Amplifier not a limiter,

Signal level can be adjusted on Crossovers etc,

At home with my stereo its diffrent but i think we are talking about big Sound systems right??
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  #8  
Old 08-22-2007, 02:49 AM
Fred Bissnette Fred Bissnette is offline
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amps on full
mixer master up almost all the way
use the input pots to level and if you dont know how to do this use a mixer that has gains on it and stay out of the red period

its usually not the resident djs that blow shit up
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  #9  
Old 08-22-2007, 03:14 AM
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Talking

yeah, RED means Limit, Saturation, many Dj[s nowdays think that red leds, means people jump more
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  #10  
Old 08-23-2007, 10:54 AM
thermionic thermionic is offline
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Quote:
Originally Posted by konbit
Does it really make any difference, sonically, if you are running your master at 5 and your channels at 9 versus your master at 9 and your channels at 5?

Yes. It makes all the difference.

Not trying to upset anyone, but it’s pretty scary that so many DJs do not have a grasp on what is the most elementary concept any DJ should know...

If you bring up the Master Amp, you bring up 6 channels' worth of noise…

If you bring up the Channel Attenuator, you bring up whatever noise is present solely on that channel…

Can anyone see what I’m getting at here?

As anyone who’s watched Spinal Tap will know, the numbers on any Level Attenuator / Gain Trim, Input or Output, are relative. That is to say that (if we talk about line-level operation as an example) ‘9’ has a totally different meaning if your input is from a -10dbV source as it would do if your input is a +4dBu source.

View the Input Attenuator pot as a ‘tap’ on a pipe that adjusts volume of water flow. If you have a hot source, say a professional D-A converter, you risk overloading the mixer’s input buffer if you run the control high. Likewise, with a pro-sumer D-A converter with a weedy output, you may need to run it really high as you don’t want to compensate with the Master for the above reasons.

If the post-Input pot Buffer is going to clip at say, +16dBu, it will clip at that level regardless of whether the Pot is at '3' or '10' - it's all down to how hot the incoming signal is.

As you can see, the number on any Input Attenuator is an arbitrary figure that is RELATIVE to what signal is going in – the numbers on their own have no meaning whatsoever.

In the case of the Master Output, regardless of what’s connected, you have a control with 6-channels’ worth of noise… Therefore, it’s worth getting as much undistorted level as you can, PRIOR to the mix-buss.

Another thing: ‘Red’ means nothing, as does ‘Green’ – you could have an LED with polka dots if you want. Again, everything is RELATIVE – according to how the unit is calibrated. Take the Rane MP24 for example; it has a meter calibration control. On an MP24, you could set the Red light to come on at 300mV RMS output – or – 1v RMS – it all depends on calibration.

One mixer could have high-voltage rails and put out +22dBm without clipping, whereas another mixer might have 2% distortion at that level… Where would ‘red’ be in this case?

Please understand that in the case of Gain Structure (any studio engineer will tell you their entire professional life is dedicated to respecting its principles), everything has to be evaluated on a case-by-case basis; there has never been and never will be one rule for all – it always horses-for-courses. Gain Structure is a totally academic concept which can be approached empirically (most DJs aren’t engineers) and optimised as such. However, it CANNOT be approached with crass generalisations about dial markings or LED colours – it’s all RELATIVE.

Note that the only exception is digital, where regardless of whether you have 16 or 24 bit, you cannot exceed 0dBfS. In the analogue world, you could have one mixer that distorts at +12dBu and another mixer that runs clean past +20dBu – it’s all down to design and headroom – something that’s specific to each mixer.

Links that follow this up:

http://www.wavemusic.com/community/s...9&postcount=11

http://www.wavemusic.com/community/s...9&postcount=25

(Last link is quite pertinent)


Justin

Last edited by thermionic : 12-04-2007 at 04:44 PM.
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  #11  
Old 08-23-2007, 10:58 AM
thermionic thermionic is offline
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BTW - Note that rotary mixers (at Line Level) typically have a passive pot that directly feeds the summing resistors / mix amp.

More feature-packed slide mixers may have a Gain Trim (which can be either a passive Potentiometer, or a Variable Resistor in the Gain Loop) prior to, or after an input buffer (or in conjunction with the buffer in the case of the Feedback Loop), which in turn feeds the fader.

In the case of the Buffered Input with Trim, the markings on the fader can actually be calibrated to have some relation to the mixer's specific Gain Structure.

In the case of a rotary, where a Line Input (or Phono amp) feed the pot directly, the markings on the Input Pot are arbitrary and are therefore relative to what's coming in, i.e they have no real meaning.

J

Last edited by thermionic : 02-04-2008 at 03:35 PM.
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  #12  
Old 08-24-2007, 01:15 AM
Fred Bissnette Fred Bissnette is offline
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i have my mixer modded with no master volume contol the master is up all the way with jumpers and the only two controls i have ar the two input controls

i notice when i go into the red all the way the sound will actually start to crunch a bit
so i stay out of this

my pots are alps dual 100k carbons

i find that on bigger systems music sounds really good this way i never use a compressor/limitor and i try to keep the eq as a cut only type control

this gives me the cleanest sound
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  #13  
Old 08-24-2007, 01:31 AM
clubman5 clubman5 is offline
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Quote:
Originally Posted by Fred Bissnette
i try to keep the eq as a cut only type control

this gives me the cleanest sound
I agree with this! My EQ,s are Cut Only, with make up gain. Providing everything else in your system is proper, cut only achieves the highest resolution!

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  #14  
Old 08-24-2007, 01:52 AM
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Scott,

I was reading this and the post on the Deep House site.

Does the method for using the UREI also apply to the Rane 2016a? I thought that since you had one, you'd know.

With the Rane, I'd set the input gain to read -3 or 0 etc. But where do you set the pots for the channel and master?

Thanks.
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  #15  
Old 08-24-2007, 08:51 AM
thermionic thermionic is offline
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Quote:
Originally Posted by mynameismatt
Scott,

I was reading this and the post on the Deep House site.

Does the method for using the UREI also apply to the Rane 2016a? I thought that since you had one, you'd know.

With the Rane, I'd set the input gain to read -3 or 0 etc. But where do you set the pots for the channel and master?

Thanks.


Matt,

You should read the post I wrote earlier.

We are talking about the most basic, elementary theory possible here...

There is and can be no one rule for all, unless you're all playing the same records... Different records are cut at a variety of differing RMS / Peak amplitudes, that means that at say, '7' each record will place different demands on your mixer's Gain Structure. Therefore, there cannot be one rule for all.

Let me repeat what I wrote earlier:

If you bring up the Master Amp, you bring up 6 channels worth of noise…

If you bring up the Channel Attenuator, you bring up whatever noise is present solely on that channel…

Capische?

Are you guys all hell-bent on using voodoo to calibrate your rigs, or do you want to use methods that have been in place since the 1920s that are proven to work, to which ALL your gear conforms to?

This place is becoming full of voodoo.


Justin
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  #16  
Old 08-24-2007, 10:38 AM
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voodoo's groove



this was a bar in New Orleans when i was growing up

the sound was pretty poor though.... IIRC

wouldn't want to replicate it....



glad to hear i am pretty much running things properly....

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  #17  
Old 08-24-2007, 11:50 AM
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I just wanted to hear how Scott was setting his Rane mixer.
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  #18  
Old 08-24-2007, 11:59 AM
thermionic thermionic is offline
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Quote:
Originally Posted by mynameismatt
I just wanted to hear how Scott was setting his Rane mixer.

Unless you have identical carts, records and DACs to Scott, the numbers on the dials of his Rane will bear no relevance your own setup whatsoever.

The numbers on the dial are arbitrary - they have no real meaning.

Justin
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  #19  
Old 08-24-2007, 12:22 PM
Kevin James Kevin James is offline
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Unity on the mix level pots on the 2016a is around 8. Easy way to test this is to set your gains however you prefer them (I usually set them so that my source hits about +2), set your mix level pot about 8 and pan back and forth on the cue/master knob. You will see that with your mix level at 8 the meter stays at a constant level weather following the cue source or the master. Then try the same while turning your mix level pot either up or down. You will then see that the meter shows a different reading between the cue source or the master channel.
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  #20  
Old 08-25-2007, 04:35 PM
clubman5 clubman5 is offline
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Quote:
Originally Posted by konbit
But how about master out and channel pots? Does it really make any difference, sonically, if you are running your master at 5 and your channels at 9 versus your master at 9 and your channels at 5?
I didnt answer this one, so Ill answer it now.

YES it makes a difference sonically, it affect S/N ratio. In plain english what this means is that wnen your input is at say 8 or 9 you have a nice strong signal, and your noise floor is well below the signal.

Now, if we do this in reverse, run your input at 5 or less, you dont have strong signal, and raising the master output control amplifies noise. You will hear more noise during quiet passages of a recording this way.

In general, you'll hear more noise this way, 60hz hum if present, residual noise of the preamp section, etc.
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  #21  
Old 11-28-2007, 02:13 AM
Reticuli Reticuli is offline
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What do you think about these mixers that say they can accept into them and output up to like 7 volts without distorting? Their meters might be designed for 1.25V for the +4 first red, but they never hugely distort no matter what you do. Isn't that design overkill that is just giving you way too much headroom that can never be exploited? Wouldn't it be better to use parts that are meant to run optimally at just over 1.25 volts?

Quote:
Originally Posted by thermionic
Yes. It makes all the difference.

Not trying to upset anyone, but it’s pretty scary that so many DJs do not have a grasp on what is the most elementary concept any DJ should know...

If you bring up the Master Amp, you bring up 6 channels worth of noise…

If you bring up the Channel Attenuator, you bring up whatever noise is present solely on that channel…

Can anyone see what I’m getting at here?

As anyone who’s watched Spinal Tap will know, the numbers on any Level Attenuator / Gain Trim, Input or Output, are relative. That is to say that (if we talk about line-level operation as an example) ‘9’ has a totally different meaning if your input is from a -10dbV source as it would do if your input is a +4dBu source.

View the Input Attenuator pot as a ‘tap’ on a pipe that adjusts volume of water flow. If you have a hot source, say a professional D-A converter, you risk overloading the mixer’s input buffer if you run the control high. Likewise, with a pro-sumer D-A converter with a weedy output, you may need to run it really high as you don’t want to compensate with the Master for the above reasons.

If the post-Input pot Buffer is going to clip at say, +16dBu, it will clip at that level regardless of whether the Pot is at '3' or '10' - it's all down to how hot the incoming signal is.

As you can see, the number on any Input Attenuator is an arbitrary figure that is RELATIVE to what signal is going in – the numbers on their own have no meaning whatsoever.

In the case of the Master Output, regardless of what’s connected, you have a control with 6-channels’ worth of noise… Therefore, it’s worth getting as much undistorted level as you can, PRIOR to the mix-buss.

Another thing: ‘Red’ means nothing, as does ‘Green’ – you could have an LED with polka dots if you want. Again, everything is RELATIVE – according to how the unit is calibrated. Take the Rane MP24 for example; it has a meter calibration control. On an MP24, you could set the Red light to come on at 300mV RMS output – or – 1v RMS – it all depends on calibration.

One mixer could have high-voltage rails and put out +22dBm without clipping, whereas another mixer might have 2% distortion at that level… Where would ‘red’ be in this case?

Please understand that in the case of Gain Structure (any studio engineer will tell you their entire professional life is dedicated to respecting its principles), everything has to be evaluated on a case-by-case basis; there has never been and never will be one rule for all – it always horses-for-courses. Gain Structure is a totally academic concept which can be approached empirically (most DJs aren’t engineers) and optimised as such. However, it CANNOT be approached with crass generalisations about dial markings or LED colours – it’s all RELATIVE.

Note that the only exception is digital, where regardless of whether you have 16 or 24 bit, you cannot exceed 0dBfS. In the analogue world, you could have one mixer that distorts at +12dBu and another mixer that runs clean past +20dBu – it’s all down to design and headroom – something that’s specific to each mixer.


Justin

Last edited by Reticuli : 11-28-2007 at 05:12 AM.
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  #22  
Old 11-28-2007, 02:35 AM
Reticuli Reticuli is offline
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YES! This is what I've been talking about. Passive little trims verses ones that allow boosts. A lot of those little bare-bones mixers (DM900, DJ-5) are pretty much at unity half-way up, not at that 80% bold mark. Above 50% they're boosting. I always thought the Bozak and Urei rotaries had gain-trim things that could boost the signal past unity for each channel. I understood how it would be better to just put one or two of those at the master & booth output and leave the channel volumes as just passive trims, but I didn't know they'd actually done that on those. So that seems -- assuming your input signals or the phono stage are hot enough -- that would minimize the noise over having 6 active gain stages combining at the mixing stage, right?

How does the mixer stage itself work? Are there different types? I take it this cannot be done passively, since there are no unpowered mixers. Hence the whole point of the invention of the mixer.

Quote:
Originally Posted by thermionic
BTW - Note that rotary mixers (at Line Level) typically have a passive pot that directly feeds the summing resistors / mix amp.

More feature-packed slide mixers may have a Gain Trim (which can be either a passive Potentiometer, or a Variable Resistor in the Gain Loop) prior to an input buffer (or in conjunction with the buffer in the case of the Feedback Loop), which in turn feeds the fader.

In the case of the Buffered Input with Trim, the markings on the fader can actually be calibrated to have some relation to the mixer's specific Gain Structure.

In the case of a rotary, where a Line Input (or Phono amp) feed the pot directly, the markings on the Input Pot are arbitrary and are therefore relative to what's coming in, i.e they have no real meaning.

J
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  #23  
Old 11-28-2007, 02:58 AM
Reticuli Reticuli is offline
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Interesting subject. First, remember gain adds noise. Second, insuffient signal level in contrast to the amount intended for a given design circuit/amp/etc reduces the optimum signal to noise ratio and potential dynamic range. You want to get it hot enough to get the best S/N ratio without adding excessive or unused gain. Don't boost the gain and then trim it down unnecessarily. Don't have insufficient gain in the mixer and then boost it at the master out or in the main amps. Minimize but optimize gain, and use all of it. The way I learned in sound engineering classes was (on a trim/gains, faders, master out unit) to find out what the proper unity of the mixer was first. Is it a consumer -10, pro +4, or 2V deal, or whatever? Then you find out if the master out volumes are trims or not. If they're just trims, you put them at max (10 usually). If they're not, you send in a 0dB ref test signal from a source into the mixer, set the gains to read 0 on the channel meters, put the faders at unity, then pipe the master/booth outs into an accurate metered piece of gear (digidesign, amps, ADAT, whatever) and turn it up so that the meters on that go to 0. When I mean 0, I'm not talking about the digital meter that maxes out at 0 full scale. I mean the EBU and DIN meters that have 0 in the yellows and let you go beyond. In Soundforge you can see both the FS and the DIN together. Leave the master/booth volumes at that spot or put a mark on them. If you have master meters, they should also reflect 0 on this tone. If not, there may be a master trim knob on the back that you can adjust until you get the master meters on the mixer at zero and the outboard gear's meters also reflecting that. You want the input meters on the mixer running (when the main part of the music is going during a mix) in the yellows around 0 on average (again, assuming the meters reflect the proper unity and design specs of the mixer) with only rarely hitting the first red that usually says +3 or +4. If it hits it repeatedly or goes to the second red, back off on the gain. Headroom is how far beyond this you can go and not get distortion from the mixer, but I always figured the best mixer designs already maximized the circuitry for the levels they were going to be used with and lots and lots of headroom was more appropriate for tape machines and main amps rather than mixers. Therm might be able to set me strait on that, though. I think what he’s saying is to get the most out a mixer you have to find out where this headroom maxes out and recalibrate your meters for that. Most mixers are not like that, I think. I know the FS digital system at 24bit gives you a bunch of "digital headroom" on the recording device where the A/D converters will not be as linear near max, but won't outright clip the waves. Even down at like -20dBFS (0dB on the DIN meter?) you've still got massive dynamics and S/N ratio possible at that bit depth. Most quality AD converters are not meant to be run near clipping. DA converters, on the other hand, don't care. But your music will sound like shit if it's so compressed to hell that you've got an RMS that high all the time. Take some of your favorite tracks and run statistics on them to find out what their average RMS is. Most rock songs are at around -6dBFS RMS. Minimalist stuff and classical will be much lower. The peaks on final digital masters can always go all the way up to 0dBFS, though the earliest Red Book DACs actually wanted you to master at just below this or they'd go ape. Not a problem anymore. I have heard it said that most quality AD converters sound alike, while even the highest-end DA converters have a lot of variation in their character. Can't confirm this myself. I'm trying to figure out what the big deal about +-3dB increments are in Sonar right now. People keep saying that's bit-perfect volume change, but I'm not sure I've been convinced yet.

Quote:
Originally Posted by DSA.audio
As I understand it, it is supposedly technically more proper to cut the amps' input sensitivity back and use the mixer with inputs/outputs at Unity

better signal to noise ratio is what i have read...

practically speaking, I normally run my system with the amps wide open and the mixer's master output pot pretty low, channel faders around 7 or so....

Last edited by Reticuli : 11-28-2007 at 05:05 AM.
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  #24  
Old 11-28-2007, 05:40 AM
Reticuli Reticuli is offline
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Maybe this is where the 1.25V verses maximum of 7V on master outs come in. Perhaps the mixers like Xones that are designed to output 1.25V with a master trim derive their concept from recording mixers intended either to feed into a recording deck (ADAT, tape, etc) or other device that wanted pro nominal (amp with a preamp of its own, soundsystem's own board, etc). While the mixers that have maximum ultra-high outputs like 7 Volts with their own gains at the end (rather than just a trim) were designed from the standpoint of preamplifiers, where the main amp would be turned up to max and the volume adjusted at the mixer end by way of this master out control. That might explain some things. If the Crown and Brystons can accept these very hot signals, that would confirm it. I'd bet the QSC wants just a pro nominal into its own onboard preamp and would distort if you pushed the inputs beyond it. Turn a QSC down and try pushing the inputs alone with a multi-volt level 1khz test signal and if it buzzes up there you'll know. With a hot-output preamp DJ mixer, you should be able to adjust the master trim on the back in concert with the main out gain to get the mixer's main meters to mimic a Crown or Bryston's meter reading so you don't have to keep looking at the amp to make sure it's not clipping. Could this mean the old rule about having an amp twice as powerful as you need is only true for subs? If a 2000watt amp has a rated s/n ratio of 90dB when wide open and the model below it is a 1000watt amp that gives 90dB when wide open and you only need 1000watts. Let's assume using the 2000W one constantly requires you to either have the amp turned down, the mixer's out turned down, or the crossover trimming it. Wouldn't it be better to use the lower output one? Assuming we're not talking about a sub where S/N is not such a big deal...

Quote:
Originally Posted by clubman5
According to both Crown and Bryston, you get the best s/n ratio running your amps input attenuators as high as possible. Preferably wide open if you can.

QSC states that the markings of the face of their amps are actual indicators of the amount of gain, and you use the input level controls on the amps to balance out to your desired level.

I am of the opinion amps input level controls wide open sounds the best, cut back at the mixer, and the crossover output level adjustments.

Others feel its better to use the amplifiers input attenuators. Of course, sometimes you may have a situation where you have no choice other than to use the amps input level controls.

You have to play around with your system, and see what you hear, if you hear a difference either way, and what, if anything, you prefer.


Last edited by Reticuli : 11-28-2007 at 06:08 AM.
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  #25  
Old 11-28-2007, 09:38 AM
thermionic thermionic is offline
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Quote:
How does the mixer stage itself work? Are there different types? I take it this cannot be done passively, since there are no unpowered mixers. Hence the whole point of the invention of the mixer.

There are several ways you can sum signals, ranging from the basic, i.e. a single resistor, to the more esoteric, such as summing transformers (the latter also being passive and the most efficient passive means of summing – albeit by far the most expensive..).

Many people who mix via DAWs choose passive mixers for purity, giving them the option of choosing an amp of their choice to boost the output :

http://www.rollmusic.com/folcrom.php

As you will note, the Folcrom uses no powered parts at all, not even a battery.

If we forget the Phono preamps for a second (let's say you’re using line sources, or an external preamp – in fact, you should think of the Bozak’s Phono card as an external preamp as it is to all intensive purposes), the signal path in a Bozak CMA-10-2-DL is entirely passive up until the summing amplifier: the pan pots are un-buffered, as are the level controls and the summing is via resistors.

However, there is a cost in all this passive circuitry - you don't get something for nothing. In the case of the Bozak, the cost is in the increased impedance. The Bozak is one of the first devices I know of to implement JFETs as a first-stage gain block after the attenuators / summing resistors. The beauty of a JFET is in its inherently high input impedance - much higher than any transistor (getting a high-Z input via a transistor requires a lot of trickery; valves and JFETs give you a 'natural' high-Z way in).

The Bozak's DC rail is +40vDC... Combined with the passive inputs / summing, this means that, firstly, you need a ridiculous amount of level to overload it. Secondly, the lower the value of your input pot, the poorer the sound quality - you should always run the input pot as high as possible, the only excuse for leaving space above the dial would be for quiet pressings, but - even then - one could argue you should max out the inputs at all times and use the Master amp to compensate for quiet LPs etc.

Why, I hear you ask, do you need to 'max out' the input pots?

2 reasons:

Firstly, because the Bozak has high DC rail voltage, you're very unlikely to hit the rails with any input source, so you might as well keep it as high as possible to maximise S/N ratio, i.e. noise performance.

Secondly, and very importantly, the higher the input pot's value, the lower the output impedance shown to the summing amp will be - this is crucial. Some people complain that the Bozak doesn't have the 'low end thump' you get with other mixers. The lower the impedance shown to the summing amp, the deeper your bass will be – i.e. the higher the pot.

Have you ever tried the Insert loop on a Bozak? Anyone that has will tell you that just connecting a cable from Out-to-In rolls off HF information. This is due to the extra cable capacitance - i.e. this part of the Bozak’s path is very high impedance.

Having a minimal signal path makes the Bozak sound clean. An unfortunate side effect is that you really want to drive external devices via a dedicated amp card, rather than from the pre-master amp section.

You could make your own mixer with 2 preamps and 4 resistors – voila - a mixer. You’d want to make sure that the amp being fed from the resistors has enough input impedance, or choose an amp with say, a FET input, to give you the high-Z naturally.

I'd like to reiterate my point earlier about evaluating every mixer on its own individual merits. I use the Bozak as a well-known case study. There is no 'one rule for all' in gain structure, and if I were to lay out the topologies for every mixer out there this post would go on for many pages! The only way to do it is to know the principles and act according to your personal hardware.

Justin
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Please note that this account is dormant for the time being. I apologise to all that have sent PMs - there are just not enough hours in the day!

Bozak CMA 10-2-DL Full Rebuild

How Mixer Level Controls Work

Important Differences Between Types of Bozak

Last edited by thermionic : 11-28-2007 at 09:47 AM.
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