Topic: What is the best part of the rig to get most of the gain from ?

[fandelive]

Hello,

my current rig consists in a ST-9100 preamp and an Edirol R09-HR.
I'd like to know which one is the best to get most of the gain from.

Thank you

[nedstruzz]

Hello,

my current rig consists in a ST-9100 preamp and an Edirol R09-HR.
I'd like to know which one is the best to get most of the gain from.

Thank you

I've always been a firm believer in proper gain structure. 

Here is my suggestion.

Set the gain on both of your pieces of equipment to roughly the same level so that neither piece of equipment is giving more or less gain than the other. 

Think of it like water running through your cables.  You don't want the 9100 open all the way just for the R-09 to squash down on the flow of signal.   Concurrently you don't want too little signal coming from the 9100 and then have the R-09 wide open.  You want nice smooth flow of signal/water. 

Now some may disagree with this method and say you want 90% of your gain coming from the 9100 and this may be true but test both methods out and see what you like. 

[yug du nord]

I have no personal proof to offer....  but there are theories too that suggest that it's best to milk as much as you can out of your ADC......  but that might depend on the actual ADC in certain rigs.

Ned's theory is your safest bet IMO. 

[stevetoney]

A third theory is to put most gain on whichever piece of gear is the quietest and/or has the lowest noise floor.

A fourth theory is the put most gain on the piece of gear that you like the sound flavor of the most.

Some people have said to rely the most on the preamp gain since that's what it's designed for, but the R-09HR is known to be very good too.

...take your pick which answer serves your goals the best because they're probably all 'right' answers.

EDIT TO ADD:  Regardless of what you decide for your gain mix, I'd make sure you're aware of the unity gain setting on the R-09HR and set your R-09HR accordingly.  While it's not a requirement to stay below it, you risk having distorted recordings (without realizing it until you get home) on the louder live shows if you set the R-09HR above the unity gain setting.  I think unity gain is something like 45 or 50.  Personally, when I had an R-09HR, I never let it go over 45.

[fmaderjr]

I think unity gain is something like 45 or 50.  Personally, when I had an R-09HR, I never let it go over 45.

Chris Church tested the R-09HR and posted that unity gain was about 38 "in most situations".

[datbrad]

I agree with Ned. You want to have your gain stages evenly distributed, not over driving or under driving any one stage. I know it will work with one component giving most of the gain, but at least for me I can almost always hear in recordings when a weak preamp output has been cranked up by the recorder (thin & scratchy), or when a too cranked preamp has been throttled down by the recorder (saturated & muddy).

BTW, the water example Ned used is a very good analogy. I have read educational material for electrical theory that uses water flow principals to teach with. It really does help it make more sense when you start talking about volts, amps, watts, and impedance when plumbing analogies are presented.

[fmaderjr]

I agree with Ned. You want to have your gain stages evenly distributed, not over driving or under driving any one stage. I know it will work with one component giving most of the gain, but at least for me I can almost always hear in recordings when a weak preamp output has been cranked up by the recorder (thin & scratchy), or when a too cranked preamp has been throttled down by the recorder (saturated & muddy).

BTW, the water example Ned used is a very good analogy. I have read educational material for electrical theory that uses water flow principals to teach with. It really does help it make more sense when you start talking about volts, amps, watts, and impedance when plumbing analogies are presented.

This may be absolutely correct for high gain preamps, but Chris Church recommends setting the recorder at unity gain to start (about 38 for the HR) and the ST-9100 at 90-100% of full gain (assuming the clipping light isn't coming on, and the show would need to be really loud for that to happen). Then if more gain needed you can get it from the recorder. This is how most  members here that have posted about it use the 9100/HR combo. Remember the ST-9100 has only 20 dB of gain. It is not going to "throttle" the recorder's line in, especially with the recorder set to unity gain to start. 

[datbrad]

I agree with Ned. You want to have your gain stages evenly distributed, not over driving or under driving any one stage. I know it will work with one component giving most of the gain, but at least for me I can almost always hear in recordings when a weak preamp output has been cranked up by the recorder (thin & scratchy), or when a too cranked preamp has been throttled down by the recorder (saturated & muddy).

BTW, the water example Ned used is a very good analogy. I have read educational material for electrical theory that uses water flow principals to teach with. It really does help it make more sense when you start talking about volts, amps, watts, and impedance when plumbing analogies are presented.

This may be absolutely correct for high gain preamps, but Chris Church recommends setting the recorder at unity gain to start (about 38 for the HR) and the ST-9100 at 90-100% of full gain (assuming the clipping light isn't coming on, and the show would need to be really loud for that to happen). Then if more gain needed you can get it from the recorder. This is how most  members here that have posted about it use the 9100/HR combo. Remember the ST-9100 has only 20 dB of gain. It is not going to "throttle" the recorder's line in, especially with the recorder set to unity gain to start.

With many of the commercially made preamps that average around 60db of total gain, when running one close to it's max gain capability, you can have increased THD in the pre, as well as overloading of the line inputs on the recorder. I also recall that the Beyer MV100 was only a 20 db gain preamp and I remember it sounded terrible cranked to the max, even though it was not too hot for the recorders.

However, if Chris Church has recommended running his very hot into the R09, he clearly designed it to do so and what you say makes total sense. The universal answer to the OP's question in the subject line for most recording setups is what Ned said.

If you are running a V2 or Sonosax cranked near the max, it would not be a good thing for most recorders I know of, definately.

[fandelive]

Thank you all for those very instructive bits.

Chris Church recommends setting the recorder at unity gain to start (about 38 for the HR) and the ST-9100 at 90-100% of full gain (assuming the clipping light isn't coming on, and the show would need to be really loud for that to happen). Then if more gain needed you can get it from the recorder. This is how most  members here that have posted about it use the 9100/HR combo.

That's a good way to start, thank you for the tip !

Regardless of what you decide for your gain mix, I'd make sure you're aware of the unity gain setting on the R-09HR and set your R-09HR accordingly.  While it's not a requirement to stay below it, you risk having distorted recordings (without realizing it until you get home) on the louder live shows if you set the R-09HR above the unity gain setting.

Thank you, I wasn't aware about the unity gain at all !!
Does that mean that if I set the ST-9100 at 90-100% of full gain and the Edirol R09-HR above 38, there's a risk of distortion ?

My mics are 4.7k (Chris Chruch) modded MM-HLSC-1's. I made a test yesterday at home in front of a speaker. I pushed the volume high, but it was definitely not as high as an average rock concert would be.
With the ST-9100 set at 90-100% of full gain and the Edirol R09-HR set at 38, the results were barely audible.
I had to crank up the input level of the Edirol at 80 (100%) to get good results (and no distortion).

I got my MM-HLSC-1's modded because they couldn't handle loud hard rock concerts bass and bass drums.
They were prefect for David Gray, but I got distorted results with Skunk Anansie or Nickelback for example. Still, the input volume never reached the 0dB limit in my Skunk Anansie or Nickelback tapes and the peak indicator never lighted on the Edirol during recording. So the problem was not about a bad input level setting I guess.

Tonedeaf : when you're talking about possible distortion with gain set above unity on the R09-HR, is it a general statement made on the average loud rock shows sound level or has it more to do with the rig parts capacity to handle loud bass / bass drums ? (I mean, whatever if the input levels settings are good and never reach the 0dB peak).

I'm asking this because you're talking about distorted recordings (without realizing it until you get home) and that's exactly what happened before my mics got modded. (didn't try the modded mics + ST-9100 preamp yet).

[fmaderjr]

Thank you, I wasn't aware about the unity gain at all !!
Does that mean that if I set the ST-9100 at 90-100% of full gain and the Edirol R09-HR above 38, there's a risk of distortion ?

tonedeaf is much more knowledgeable than I am about the general principles involved in recording, but I suspect that if the concert has a low enough sound pressure level that you are not getting enough gain with the ST-9100 at 100% and the HR at 38, you will not be risking distortion if you raise the HR's level quite a bit as long as the meters are staying under 0 dB. However if the concert is quiet enough, there is a point where you could be adding audible noise (hiss) to your recording from the HR's preamp. I don't know where that point is, but I'm guessing you could go over 60/100 (maybe well over) without adding noise. The older R-09's pre was decent until you raised if above 25/30 and then it started to get very noisy. The HR's pre is supposed to be much better.

If it takes a lot of gain from the HR to get the levels even to peak at -12 or so, I wouldn't raise the HR's level any further though. With 24 bit, you can add the extra gain in post without adding audible noise. I generally aim for peaks no higher than somewhere between -12 and -6 anyway, so that I don't need to worry about a sudden volume peak causing clipping (and so I don't need to stress myself out due to having to constantly monitor my levels).

It is my understanding that if your mics themselves are not distorting (as yours did before the modification) and your preamp is not distorting (check the clip light) you are not going to get distortion from the HR when it is set to unity gain and the meters are staying under 0 dB.

[runonce]

Without regard to any specific device....

You want to get max/safe gain as soon as possible in your signal chain.

Some get enough gain with no preamp -  so only 1 gain stage. (mic > line)

Some use two gain stages. Preamp > Recorder gain. You want to get the gain at the first stage...Ideally the second should be unity - or something specific for that device. (despite the term, it seems "line in" isnt a totally reliable/universal spec)

If you undergain your 1st stage and boost in a second stage...you also increase the noise from the first device by the same amount.

[datbrad]

Without regard to any specific device....

You want to get max/safe gain as soon as possible in your signal chain.

Some get enough gain with no preamp -  so only 1 gain stage. (mic > line)

Some use two gain stages. Preamp > Recorder gain. You want to get the gain at the first stage...Ideally the second should be unity - or something specific for that device. (despite the term, it seems "line in" isnt a totally reliable/universal spec)

If you undergain your 1st stage and boost in a second stage...you also increase the noise from the first device by the same amount.

This^

(btw, there are universal standards for line level. Generally there are devices with unbalanced consumer line inputs at -10db sensitivity, and professional balanced line inputs at +4db sensitivity. Obviously, this 14db difference in sensitivity is significant, and something that must be considered as a place to start when getting distortion on line inputs, with recording levels that do not go over zero. Most recorders today have active electronics between the physical input and the gain control, which is why they can overload so easily with unbalanced line inputs that are -10db consumer line level.)

[stevetoney]

Thank you, I wasn't aware about the unity gain at all !!
Does that mean that if I set the ST-9100 at 90-100% of full gain and the Edirol R09-HR above 38, there's a risk of distortion ?

tonedeaf is much more knowledgeable than I am about the general principles involved in recording, but I suspect that if the concert has a low enough sound pressure level that you are not getting enough gain with the ST-9100 at 100% and the HR at 38, you will not be risking distortion if you raise the HR's level quite a bit as long as the meters are staying under 0 dB. However if the concert is quiet enough, there is a point where you could be adding audible noise (hiss) to your recording from the HR's preamp. I don't know where that point is, but I'm guessing you could go over 60/100 (maybe well over) without adding noise. The older R-09's pre was decent until you raised if above 25/30 and then it started to get very noisy. The HR's pre is supposed to be much better.

If it takes a lot of gain from the HR to get the levels even to peak at -12 or so, I wouldn't raise the HR's level any further though. With 24 bit, you can add the extra gain in post without adding audible noise. I generally aim for peaks no higher than somewhere between -12 and -6 anyway, so that I don't need to worry about a sudden volume peak causing clipping (and so I don't need to stress myself out due to having to constantly monitor my levels).

It is my understanding that if your mics themselves are not distorting (as yours did before the modification) and your preamp is not distorting (check the clip light) you are not going to get distortion from the HR when it is set to unity gain and the meters are staying under 0 dB.

Thanks for the compliment fmaderjr, but I'm not more knowledgeable, just more than willing to share my opinion.      Ton of difference!  LOL.

For the sake of the OP, here's what I've learned (from others here on TS.com) that you want to be aware of.  Yes, the R-09HR has a unity gain point...which apparently is right around the 38 or 40 mark.  Some people have in the past got home from a loud rock concert and their preamp set quite low and was never distorting, so they figured they had a good recording just from watching their levels.  But then when they got home, they discovered that their recording was distorted and couldn't figure out why since their preamp levels were low...and this could be true even when the recorder levels were peaking say at -12db.  The reason was that the distortion happened at the recorder side. 

So, by knowing where unity gain is on the R-09HR that can help prevent this from happening.  That said, I do think fmaderjr is right that it's OK to go above unity gain, but it's probably also safe to say that the louder it gets the more there's a chance of issues from the recorder side.  OTOH, as fmaderjr says above, I also have always felt safer to leave my levels peaking low (and raise them in post) than going over unity gain on the R-09HR.

[runonce]

Without regard to any specific device....

You want to get max/safe gain as soon as possible in your signal chain.

Some get enough gain with no preamp -  so only 1 gain stage. (mic > line)

Some use two gain stages. Preamp > Recorder gain. You want to get the gain at the first stage...Ideally the second should be unity - or something specific for that device. (despite the term, it seems "line in" isnt a totally reliable/universal spec)

If you undergain your 1st stage and boost in a second stage...you also increase the noise from the first device by the same amount.

This^

(btw, there are universal standards for line level. Generally there are devices with unbalanced consumer line inputs at -10db sensitivity, and professional balanced line inputs at +4db sensitivity. Obviously, this 14db difference in sensitivity is significant, and something that must be considered as a place to start when getting distortion on line inputs, with recording levels that do not go over zero. Most recorders today have active electronics between the physical input and the gain control, which is why they can overload so easily with unbalanced line inputs that are -10db consumer line level.)

I agree and understand the consumer/pro level difference. A pitfall for sure.

Im referring more to the cheaper handheld recorders that have no obvious or intuitive way of setting it to unity.
And odd control systems and undefeatable settings.
For example I have to dial my mixer down a few notches to patch a H2 versus a JB3...at their presumptive "line in" settings.

[fmaderjr]

Some people have in the past got home from a loud rock concert and their preamp set quite low and was never distorting, so they figured they had a good recording just from watching their levels.  But then when they got home, they discovered that their recording was distorted and couldn't figure out why since their preamp levels were low...and this could be true even when the recorder levels were peaking say at -12db.  The reason was that the distortion happened at the recorder side. 

As you know, this could also happen if the mics couldn't handle the sound pressure levels (like unmodded AT853's and some of the less expensive mics). I take it you ruled out that possibility after reading the posts?

Knowing nothing else about the circumstances, I would have guessed that the mics would be the most likely source of the problem. According to guysonic, the HR's line in is supposed to be able to handle a very hot input without clipping and I wouldn't have thought that raising the gain (with the meters still under 0 dB) would cause it to clip.

If I'm wrong about this, I would certainly like to know it. I don't know anything about this from experience. I rarely have my recorders set much above unity gain because I can get most of the gain I need from my pre.