[Tobiah[_4_]]

http://tinyurl.com/4ymjcqr

I just want to amplify the control room outs of
a Mackie 1402VLZ Pro for recording and general use.
Perhaps there is a reason that the price sounds
reasonable?

Also, I know that amps and speakers seem to have
ways of grossly inflating their watt ratings. I'm
not really sure how much I need? My current (30 year old)
receiver is rated at 40 watts, and I don't normally turn
it up more than half way. I was wondering though, if
it's better to get a more powerful amp just because it
will be able to handle what I need so easily? I was thinking
too however, that maybe the more powerful amp would be
noisier.

My speakers are likely 8 ohm. They are Energy C7's. I know
you guys don't like them. After the amp, I'll go for some
decent monitors, and bug you all about that when the time comes.

Thanks,

Tobiah

[Scott Dorsey]

Tobiah wrote:
http://tinyurl.com/4ymjcqr

I just want to amplify the control room outs of
a Mackie 1402VLZ Pro for recording and general use.
Perhaps there is a reason that the price sounds
reasonable?

Never used one, but switching supplies make a lot of power very cheap
in the PA amp market today.

Also, I know that amps and speakers seem to have
ways of grossly inflating their watt ratings. I'm
not really sure how much I need? My current (30 year old)
receiver is rated at 40 watts, and I don't normally turn
it up more than half way. I was wondering though, if
it's better to get a more powerful amp just because it
will be able to handle what I need so easily? I was thinking
too however, that maybe the more powerful amp would be
noisier.

The problem is that to double the loudness, you need ten times the power.
So you can go from very little power to a lot of power very quickly.

My speakers are likely 8 ohm. They are Energy C7's. I know
you guys don't like them. After the amp, I'll go for some
decent monitors, and bug you all about that when the time comes.

They aren't horrible, but they are also very efficient. A little
Adcom GFA 535 off of Ebay will sound good and will be plenty of power.
Plenty of cheap used Haflers out there too.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Tobiah[_4_]]

The problem is that to double the loudness, you need ten times the power.
So you can go from very little power to a lot of power very quickly.

I would have thought that it would be the square or the cube of
the original amount. I didn't think nature or even mathematics cared
for the number 10.

They aren't horrible, but they are also very efficient.

I'm going to read that as 'and' they are also very efficient.

Thanks for you comments.

Tobiah

[Scott Dorsey]

Tobiah wrote:
The problem is that to double the loudness, you need ten times the power.
So you can go from very little power to a lot of power very quickly.

I would have thought that it would be the square or the cube of
the original amount. I didn't think nature or even mathematics cared
for the number 10.

It's entirely a perceptual thing. Ask people to adjust a knob so one sound
is twice as loud as another, and that's about where they set it.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[John Williamson]

Tobiah wrote:

The problem is that to double the loudness, you need ten times the power.
So you can go from very little power to a lot of power very quickly.

I would have thought that it would be the square or the cube of
the original amount. I didn't think nature or even mathematics cared
for the number 10.

It's a logarithmic scale. Add ten decibels, and the power is increased
by ten times. Add twenty, and the power is multiplied by a hundred. As
your ears are inversely logarithmic in their sensitivity to volume
increases, ten decibels extra doubles the perceived volume, and twenty
doubles it again, roughly speaking.

Three decibels (Actually 3.01 decibels)doubles the power (10X (log 2)),
but makes very little perceived difference to loudness. A one decibel
change (About ten percent change in power) is the minimum change
detectable by most people.

--
Tciao for Now!

John.

[Trevor]

"Scott Dorsey" wrote in message
...
Tobiah wrote:
The problem is that to double the loudness, you need ten times the
power.
So you can go from very little power to a lot of power very quickly.

I would have thought that it would be the square or the cube of
the original amount. I didn't think nature or even mathematics cared
for the number 10.

It's entirely a perceptual thing. Ask people to adjust a knob so one
sound
is twice as loud as another, and that's about where they set it.


That's the claim, but "double" has no real meaning when talking about
percieved loudness. 10dB is simply a lot louder to almost anybody, 3 dB only
a little louder. So these figures do not come from any natural mathematical
formula, simply observational guesstimates of an ill defined problem.
The actual power involved is definitely based on mathematics and measurement
however.

Trevor.

[gregz]

Tobiah wrote:
http://tinyurl.com/4ymjcqr

I just want to amplify the control room outs of
a Mackie 1402VLZ Pro for recording and general use.
Perhaps there is a reason that the price sounds
reasonable?

Also, I know that amps and speakers seem to have
ways of grossly inflating their watt ratings. I'm
not really sure how much I need? My current (30 year old)
receiver is rated at 40 watts, and I don't normally turn
it up more than half way. I was wondering though, if
it's better to get a more powerful amp just because it
will be able to handle what I need so easily? I was thinking
too however, that maybe the more powerful amp would be
noisier.

Running half power is dangerously close to clipping, but you might get an
amp that goes above 10 on the dial.

Greg


My speakers are likely 8 ohm. They are Energy C7's. I know
you guys don't like them. After the amp, I'll go for some
decent monitors, and bug you all about that when the time comes.

Thanks,

Tobiah

[Ron Capik[_3_]]

On 10/24/2011 9:02 PM, gregz wrote:
wrote:
http://tinyurl.com/4ymjcqr

I just want to amplify the control room outs of
a Mackie 1402VLZ Pro for recording and general use.
Perhaps there is a reason that the price sounds
reasonable?

Also, I know that amps and speakers seem to have
ways of grossly inflating their watt ratings. I'm
not really sure how much I need? My current (30 year old)
receiver is rated at 40 watts, and I don't normally turn
it up more than half way. I was wondering though, if
it's better to get a more powerful amp just because it
will be able to handle what I need so easily? I was thinking
too however, that maybe the more powerful amp would be
noisier.

Running half power is dangerously close to clipping, but you might get an
amp that goes above 10 on the dial.

Greg

[1] Proper gain structure should not clip at full volume.
[2] Volume controls are not linear.
[3] YMMV (but not by a lot, else something is wrong)

Later...
Ron Capik
--

[Frank Stearns]

John Williamson writes:

Tobiah wrote:

The problem is that to double the loudness, you need ten times the power.
So you can go from very little power to a lot of power very quickly.

I would have thought that it would be the square or the cube of
the original amount. I didn't think nature or even mathematics cared
for the number 10.

It's a logarithmic scale. Add ten decibels, and the power is increased
by ten times. Add twenty, and the power is multiplied by a hundred. As
your ears are inversely logarithmic in their sensitivity to volume
increases, ten decibels extra doubles the perceived volume, and twenty
doubles it again, roughly speaking.

Three decibels (Actually 3.01 decibels)doubles the power (10X (log 2)),
but makes very little perceived difference to loudness. A one decibel
change (About ten percent change in power) is the minimum change
detectable by most people.


Often true in isolation (say a single track solo'd and moved up or down 1 dB), but
this is not always so given some kind of context.

As a mix nears completion and "tightens" to where everything is where it should be,
fractional dB changes in level and EQ can be quite obvious. 0.2-0.5 dB mix changes
on single tracks at various points will often be the difference between a good mix
and the ideal mix.

I find it fascinating that the ear/brain seems to respond this way. It's my guess
that a large contributor to this is the "unnatural" way we sometimes record an
ensemble, where every instrument & voice is captured on its own track. Could be that
a fractional dB on a close-mic'd source "leverages" that slight electrical change to
a larger perceived change when sitting with everything else that's also been
recorded abnormally close. Just a guess, though.

I'm not making a value judgement about recording techniques. I record both near and
far (and often in combination) and would never dismiss one technique for the other
-- either or a combination depends on the music and the eventual use.

YMMV.

Frank
Mobile Audio
--

[Scott Dorsey]

Frank Stearns wrote:

As a mix nears completion and "tightens" to where everything is where it should be,
fractional dB changes in level and EQ can be quite obvious. 0.2-0.5 dB mix changes
on single tracks at various points will often be the difference between a good mix
and the ideal mix.

And I'd like to point out that the ability to hear these changes is really
the difference between good monitors and bad monitors.

I could make pretty dramatic EQ changes without hearing any damn change at
all, on the Altec 604s. On modern monitors I can make much more subtle
changes and the effects are far more audible.

I find it fascinating that the ear/brain seems to respond this way. It's my guess
that a large contributor to this is the "unnatural" way we sometimes record an
ensemble, where every instrument & voice is captured on its own track. Could be that
a fractional dB on a close-mic'd source "leverages" that slight electrical change to
a larger perceived change when sitting with everything else that's also been
recorded abnormally close. Just a guess, though.

I don't buy it, because I can hear similar things even on far field mixes
although it's less prominent.

i'm not making a value judgement about recording techniques. I record both near and
far (and often in combination) and would never dismiss one technique for the other
-- either or a combination depends on the music and the eventual use.

"There's only two kinds of music, good and bad." -- Count Basie.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Peter Larsen[_3_]]

Tobiah wrote:

http://tinyurl.com/4ymjcqr

I just want to amplify the control room outs of
a Mackie 1402VLZ Pro for recording and general use.
Perhaps there is a reason that the price sounds
reasonable?

Can't comment on this specific amp.

Also, I know that amps and speakers seem to have
ways of grossly inflating their watt ratings.

Is is wise to read spec sheets carefully. Look closely at the difference
between rated power - and what kind of power, ie. to what spec/standard - in
different load impedances.

I'm not really sure how much I need?

There is a simple guideline answer to this, assuming you have a reasonably
sized room and sits ... tja da dum ... 10 feet from your loudspeakers. The
guideline is that you need 10 times the power required for one loudspeaker
to produce 96 dB at a distance of one meter.

My current (30 year old)
receiver is rated at 40 watts, and I don't normally turn
it up more than half way.

So you may run it flat out considering that it is designed for lower line
level, 500 mV to a volt, than the 2 volt max output from your CD player.
Traditionally such a receiver is designed with at least 10 dB make-up gain,
i.e. for 240 millivolts in for rated power out at volume control fully
maxed. The mid position is traditionally -22 dB and -10, nominal power out
with receiver signal or probable pickup cartridge, is at half past 1.

I was wondering though, if
it's better to get a more powerful amp just because it
will be able to handle what I need so easily?

It is a good habit to define the problem you want solved. What problem do
you have with your current setup that needs solving?

I was thinking
too however, that maybe the more powerful amp would be
noisier.

Not necessarily, you should however gain-stage your system properly,
especially with large poweramps. If the amp has an input attenuator then
turn it down, try 12 O'clock, if that works for you then leave it there.

My speakers are likely 8 ohm. They are Energy C7's. I know
you guys don't like them.

No you don't, but since you expect me to dislike them, then tell me what is
wrong about them for the intended use.

After the amp, I'll go for some
decent monitors, and bug you all about that when the time comes.

KEF Q15 and Q15.2 are just that and a well kept secret on the second hand
market, except that owners don't seem to like parting with them so you need
to keep your eyes open, the .2' are best, both have textile dome tweeters,
the .2 uses silk.

Tobiah

Kind regards

Peter Larsen