scaling in digital out to analog

[cporro]

i've heard it's best to not scale digital but rather attenuate the
analog signal.

here is why i ask. i have a RME Fireface 800. i am outputing a -50dbfs
signal to my amp to feed my mixcubes. the amp for the mixcubes is a
50watt/channel older Bryston B2. the thing is way more then i need and
there appears to be no trim control.

same situation...my mackie hr824s are trimmed very low (via screw on
back) so that i can output from my Fireface with the fader at 0dbfs.

a while back i did a listening test where i measured the listening
level at maybe 75db. on one trial i had my mackies trim all the way up
and a very low digital output. the other my digital fader was at 0dbfs
and the mackies were turned very low. i did not notice a difference
but then again it took a while to set this up and calibrate the
listening level.

so what is the deal? or is there no deal at all? or is it gear
dependent?

thx

[Scott Dorsey]

cporro > wrote:
>i've heard it's best to not scale digital but rather attenuate the
>analog signal.

Sometimes.

>here is why i ask. i have a RME Fireface 800. i am outputing a -50dbfs
>signal to my amp to feed my mixcubes. the amp for the mixcubes is a
>50watt/channel older Bryston B2. the thing is way more then i need and
>there appears to be no trim control.

So get an amp that has a gain control on it. Or add an attenuator.

>same situation...my mackie hr824s are trimmed very low (via screw on
>back) so that i can output from my Fireface with the fader at 0dbfs.
>
>a while back i did a listening test where i measured the listening
>level at maybe 75db. on one trial i had my mackies trim all the way up
>and a very low digital output. the other my digital fader was at 0dbfs
>and the mackies were turned very low. i did not notice a difference
>but then again it took a while to set this up and calibrate the
>listening level.

The RME is pretty damn linear. You can afford to throw away twenty or
thirty dB and not notice. I wouldn't worry about it. But if it bothers
you, use an inline attenuator.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[cporro]

see scott, i worry too much. it's what's happens when you haven't done
things a whole lot. i'm working on the whole lot part i assure you.

it only worries me if the sound suffers...or if i destroy my
speakers.

do you have a rec on the attenuator? i am very wary of just buying
gear. thx.

[Scott Dorsey]

cporro > wrote:
>see scott, i worry too much. it's what's happens when you haven't done
>things a whole lot. i'm working on the whole lot part i assure you.

You need to stop worrying so much. Have a cup of tea.

>it only worries me if the sound suffers...or if i destroy my
>speakers.

These are Horrortones, they're supposed to sound awful and they are impossible
to destroy. After listening to them for a couple hours, you'll want to
destroy them anyway.

>do you have a rec on the attenuator? i am very wary of just buying
>gear. thx.

Shure A15AS will work, though you only have three choices of attenuation.
There are cheaper ones and more flexible ones but the Shure is the one
that studios seem to have traditionally kept around in the junk drawer.
You can make your own with a box and a pot if you'd prefer.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[cporro]

> You need to stop worrying so much. *Have a cup of tea.
>

worrying is one of my hobbies. you wouldn't tell woodie allen to stop
masterbating would you?

> These are Horrortones, they're supposed to sound awful and they are impossible
> to destroy. *After listening to them for a couple hours, you'll want to
> destroy them anyway.

so far i've found i need to listen to them at very low volumes. =<
60db. at louder ones they kinda hurt.

> Shure A15AS will work, though you only have three choices of attenuation.
> There are cheaper ones and more flexible ones but the Shure is the one
> that studios seem to have traditionally kept around in the junk drawer.
> You can make your own with a box and a pot if you'd prefer.

this is for attenuating between the output of my converter and the
amp. i was thinking of attenuating the output of the amp. but maybe
that is backwards. my thinking is the amp will be expecting a minimum
signal.

[Peter Larsen[_3_]]

cporro wrote:

>> You need to stop worrying so much. Have a cup of tea.

> worrying is one of my hobbies. you wouldn't tell woodie allen to stop
> masterbating would you?

>> These are Horrortones, they're supposed to sound awful and they are
>> impossible to destroy. After listening to them for a couple hours,
>> you'll want to destroy them anyway.

> so far i've found i need to listen to them at very low volumes. =<
> 60db. at louder ones they kinda hurt.

>> Shure A15AS will work, though you only have three choices of
>> attenuation. There are cheaper ones and more flexible ones but the
>> Shure is the one
>> that studios seem to have traditionally kept around in the junk
>> drawer.
>> You can make your own with a box and a pot if you'd prefer.

> this is for attenuating between the output of my converter and the
> amp. i was thinking of attenuating the output of the amp. but maybe
> that is backwards. my thinking is the amp will be expecting a minimum
> signal.

What you need is 15 dB attenuation or so between converter and amp, fixed is
fine, 20 may be OK. That puts you in the ballpark, make remaining adjustmens
via sound card mixer or whatever. Also - generally, nno guarantee - gives
you the advantage of being able to hotplug into the amp without destroying
loudspeakers, hearing and the realitionship to the resident studio cat, if
any.

Kind regards

Peter Larsen

[Scott Dorsey]

cporro > wrote:
>> These are Horrortones, they're supposed to sound awful and they are impos=
>sible
>> to destroy. =A0After listening to them for a couple hours, you'll want to
>> destroy them anyway.
>
>so far i've found i need to listen to them at very low volumes. =3D<
>60db. at louder ones they kinda hurt.

They hurt at lower volumes too, I think.

>> Shure A15AS will work, though you only have three choices of attenuation.
>> There are cheaper ones and more flexible ones but the Shure is the one
>> that studios seem to have traditionally kept around in the junk drawer.
>> You can make your own with a box and a pot if you'd prefer.
>
>this is for attenuating between the output of my converter and the
>amp. i was thinking of attenuating the output of the amp. but maybe
>that is backwards. my thinking is the amp will be expecting a minimum
>signal.

If you attenuate the output of the amp you'll have to use a huge resistor
bank that will dissipate a lot of heat. The amplifier does not care about
any minimum signal level, not if it's any good anyway.

The A15AS on the input of the amp will be fine. Or you can make your own.
Or you can get a real monitor panel which will allow you to calibrate several
sets of monitors to have the same level.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."