Roland SPD-S clipping

[Pete Pemberton]

I grabbed one at a pawn shop, seems to work fine, and I don't notice
any artifacts or clipping through monitoring or headphones. Played a
gig last Saturday with it, and did notice some clipping. Checked the
settings the soundguy had, he had the slider well down below Unity, and
the gain up. He said he balanced it using the PFL feature (Allen and
Heath Mixwizard or whatever, it's a newer 16 channel mini mixer).

So I am assuming that he was overdriving the channel resulting in the
clipping (and I heard it in my in ear monitors as qwell, so I know it
was the whole channel, not just what I heard. He verified that it was
clipping through the mains as well.

Thoughts?

In my understanding of Unity gain, once you set the PFL/gain structure
bring the sliders up to as close to unity as you can, and lower the
main sliders if the sum is too loud, yes?

PP

[-MIKE-]

I grabbed one at a pawn shop, seems to work fine, and I don't notice any
artifacts or clipping through monitoring or headphones. Played a gig
last Saturday with it, and did notice some clipping. Checked the
settings the soundguy had, he had the slider well down below Unity, and
the gain up. He said he balanced it using the PFL feature (Allen and
Heath Mixwizard or whatever, it's a newer 16 channel mini mixer).
So I am assuming that he was overdriving the channel resulting in the
clipping (and I heard it in my in ear monitors as qwell, so I know it
was the whole channel, not just what I heard. He verified that it was
clipping through the mains as well.
Thoughts?
In my understanding of Unity gain, once you set the PFL/gain structure
bring the sliders up to as close to unity as you can, and lower the main
sliders if the sum is too loud, yes?
PP

Unity means what is coming in to the fader, is going out.
There is no attenuation, nor amplification going on.
Technically, *if* he used the PFL to set the gain pot, it should be fine.
But there could be other things causing trouble. He could have it
coming in mic level instead if line level, He could have a pad on
somewhere: -10, -20, etc, that he took off accidentally.

To avoid it in the future... I would put a sample into the SPD-S of a
test tone, 1khtz at 0dB or -10dB. You can play that sample for the
sound guy to set his levels. That, or a super compressed song file that
has vety little dynamics.

Also, does the SPD-S have a mic/line setting for the mater output.
Sounds like maybe you were sending a mic signal, and he had to gain it
all the way up.

[Pete Pemberton]

Post by -MIKE-

I grabbed one at a pawn shop, seems to work fine, and I don't notice any
artifacts or clipping through monitoring or headphones. Played a gig
last Saturday with it, and did notice some clipping. Checked the
settings the soundguy had, he had the slider well down below Unity, and
the gain up. He said he balanced it using the PFL feature (Allen and
Heath Mixwizard or whatever, it's a newer 16 channel mini mixer).
So I am assuming that he was overdriving the channel resulting in the
clipping (and I heard it in my in ear monitors as qwell, so I know it
was the whole channel, not just what I heard. He verified that it was
clipping through the mains as well.
Thoughts?
In my understanding of Unity gain, once you set the PFL/gain structure
bring the sliders up to as close to unity as you can, and lower the main
sliders if the sum is too loud, yes?
PP

Unity means what is coming in to the fader, is going out.
There is no attenuation, nor amplification going on.
Technically, *if* he used the PFL to set the gain pot, it should be fine.
But there could be other things causing trouble. He could have it
coming in mic level instead if line level, He could have a pad on
somewhere: -10, -20, etc, that he took off accidentally.
To avoid it in the future... I would put a sample into the SPD-S of a
test tone, 1khtz at 0dB or -10dB. You can play that sample for the
sound guy to set his levels. That, or a super compressed song file
that has vety little dynamics.
Also, does the SPD-S have a mic/line setting for the mater output.
Sounds like maybe you were sending a mic signal, and he had to gain it
all the way up.

Ahh, mic vs line level. I always forget about that. Well, I did use a
direct box, with the pad OFF, then it was sent through the snake into
the mic input. The DB has -20 and -40 switches, IIRC.

There isn't a swich on the output, the SPD-S manual says the output is
at -10 dBu (standard line level signal, yes?) so I should NOT use the
DB, then use an adapter on the snake and run it into the line in on the
mixer? Or use the DB at -20 to compensate for the pre-amp?

I hate this crap....

:-P

PP

[Brandon Paluzzi]

Post by Pete Pemberton

Post by -MIKE-

I grabbed one at a pawn shop, seems to work fine, and I don't notice any
artifacts or clipping through monitoring or headphones. Played a gig
last Saturday with it, and did notice some clipping. Checked the
settings the soundguy had, he had the slider well down below Unity, and
the gain up. He said he balanced it using the PFL feature (Allen and
Heath Mixwizard or whatever, it's a newer 16 channel mini mixer).
So I am assuming that he was overdriving the channel resulting in the
clipping (and I heard it in my in ear monitors as qwell, so I know it
was the whole channel, not just what I heard. He verified that it was
clipping through the mains as well.
Thoughts?
In my understanding of Unity gain, once you set the PFL/gain structure
bring the sliders up to as close to unity as you can, and lower the main
sliders if the sum is too loud, yes?
PP

Unity means what is coming in to the fader, is going out.
There is no attenuation, nor amplification going on.
Technically, *if* he used the PFL to set the gain pot, it should be fine.
But there could be other things causing trouble.  He could have it
coming in mic level instead if line level,  He could have a pad on
somewhere: -10, -20, etc, that he took off accidentally.
To avoid it in the future...  I would put a sample into the SPD-S of a
test tone, 1khtz at 0dB or -10dB.  You can play that sample for the
sound guy to set his levels.  That, or a super compressed song file
that has vety little dynamics.
Also, does the SPD-S have a mic/line setting for the mater output.
Sounds like maybe you were sending a mic signal, and he had to gain it
all the way up.

Ahh, mic vs line level. I always forget about that. Well, I did use a
direct box, with the pad OFF, then it was sent through the snake into
the mic input. The DB has -20 and -40 switches, IIRC.
There isn't a swich on the output, the SPD-S manual says the output is
at -10 dBu (standard line level signal, yes?) so I should NOT use the
DB, then use an adapter on the snake and run it into the line in on the
mixer? Or use the DB at -20 to compensate for the pre-amp?
I hate this crap....
:-P
PP

The SPD is giving line level -- the mixer wants everything to look
like a mic. Run it into the DI, which will set the impedance and
balance the line.

The problem is most likely BCOS. Between console and speakers ;-)
He's not setting his gain structure properly. If it's clipping in
your monitor send, then it's most likely not the channel or master
faders, it's the channel gain pot. If he's trying to use the PFL
light, it's very likely not going to work for level setting -- drum
transients are so quick that they often don't hit the PFL lights
accurately. He's going to have to use his ears to set the gain to a
level that is as hot as possible without introducing audible
clipping / distortion.

Once the gain stage is set correctly, then he can use the channel
fader to place the instrument in the mix. Master faders should
generally be at unity. Similarly, the aux output (for monitors)
should generally be at unity, and use the channel aux output to set
the level of the SPD in your monitor.


b

[-MIKE-]

Post by Pete Pemberton
Ahh, mic vs line level. I always forget about that. Well, I did use a
direct box, with the pad OFF, then it was sent through the snake into
the mic input. The DB has -20 and -40 switches, IIRC.
There isn't a swich on the output, the SPD-S manual says the output is
at -10 dBu (standard line level signal, yes?) so I should NOT use the
DB, then use an adapter on the snake and run it into the line in on the
mixer? Or use the DB at -20 to compensate for the pre-amp?

I don't think the SPD-S output is balanced, so it's a good idea to use a
direct box. Not all direct boxes pad the signal down to mic level.
Yours has the pads on it, which tells me it doesn't. Most Allen and
Heath mixers have inputs switchable between mic/line level.

If it has a line level, you can send from the direct box with no pad.
If it only takes line level, put the pad on -40 and you should be fine.