[gareth magennis]

Hi,

just bought the M Audio Microtrack 2 digital recorder. The TRS inputs are
labelled Mic/Line though there doesn't seem to be any switch as such, just
the variable input gain.
Unfortunately there is not enough attenuation available to prevent a
standard CD RCA output from clipping.

This seems very odd. If it is designed for a line input it surely should be
able to cope with a -10dB CD player, but it can't.

Maybe I'm missing something but I can't find a way to turn it down anywhere.



I've updated to the latest firmware, no difference.


Cheers,



Gareth.

[gareth magennis]

"Gareth Magennis" wrote in message
...
Hi,

just bought the M Audio Microtrack 2 digital recorder. The TRS inputs are
labelled Mic/Line though there doesn't seem to be any switch as such, just
the variable input gain.
Unfortunately there is not enough attenuation available to prevent a
standard CD RCA output from clipping.

This seems very odd. If it is designed for a line input it surely should
be able to cope with a -10dB CD player, but it can't.

Maybe I'm missing something but I can't find a way to turn it down
anywhere.



I've updated to the latest firmware, no difference.


Cheers,



Gareth.




Hmm, further reading shows advice from M Audio NOT to ground the Ring
connection. Which is what I did.


In reality this will be connected to a transformer isolation box. I'll try
that tomorrow. It seems this is not designed or able to record unbalanced
line level signals. They don't tell you that in the literature.



Gareth.

[Mike Rivers]

Gareth Magennis wrote:

just bought the M Audio Microtrack 2 digital recorder. The TRS inputs are
labelled Mic/Line though there doesn't seem to be any switch as such, just
the variable input gain.
Unfortunately there is not enough attenuation available to prevent a
standard CD RCA output from clipping.

You'll need to get an in-line attenuator or else turn down the output
level of the CD player. LIke many recorders of this ilk, the input stage
craps out at a prettly low level. According to the specifications (on
the web site - I guess they were embarrassed to put this in the manual
where a user would find it):

Maximum Input Level at minimum gain +4.3 dBu, balanced

Your "standard" CD player probably has a nominal output level of -10 dBV
at a conservative CD level, with around 16 dB of headroom (-16 dBFS on
the CD gives an output level of =10 dBV). But modern CDs generally run
with the peaks at 0 dBFS. That means that peaks out of your CD player
will be around +6 dBV, which is +8 dBu, 4 dB above the clipping level of
your recorder. Yeah, that really sucks.

What you need is a box with a stereo pot in it so you can turn down the
level of things that don't have an output level control. It's a good
construction project and you can make it with whatever kind of
connectors you think you'll use most. You could use the headphone output
of the CD player - headphone outputs always have a volume control. But
you'll need the appropriate cable and probably adapters.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Geoff]

Mike Rivers wrote:
Gareth Magennis wrote:

just bought the M Audio Microtrack 2 digital recorder. The TRS
inputs are labelled Mic/Line though there doesn't seem to be any
switch as such, just the variable input gain.
Unfortunately there is not enough attenuation available to prevent a
standard CD RCA output from clipping.

You'll need to get an in-line attenuator or else turn down the output
level of the CD player. LIke many recorders of this ilk, the input
stage craps out at a prettly low level. According to the
specifications (on the web site - I guess they were embarrassed to
put this in the manual where a user would find it):

Maximum Input Level at minimum gain +4.3 dBu, balanced

Your "standard" CD player probably has a nominal output level of -10
dBV at a conservative CD level, with around 16 dB of headroom (-16
dBFS on the CD gives an output level of =10 dBV). But modern CDs
generally run with the peaks at 0 dBFS. That means that peaks out of
your CD player will be around +6 dBV, which is +8 dBu, 4 dB above the
clipping level of your recorder. Yeah, that really sucks.

Many players have a nominal ouput of -10dBV, and others have a nominal
output of 2V. Some have both.

geoff

[Geoff]

geoff wrote:


Many players have a nominal ouput of -10dBV, and others have a nominal
output of 2V. Some have both.


.... each which I would expect to be the output levels at 0dBFS.

geoff

[gareth magennis]

"Mike Rivers" wrote in message
...
Gareth Magennis wrote:

just bought the M Audio Microtrack 2 digital recorder. The TRS inputs
are labelled Mic/Line though there doesn't seem to be any switch as such,
just the variable input gain.
Unfortunately there is not enough attenuation available to prevent a
standard CD RCA output from clipping.

You'll need to get an in-line attenuator or else turn down the output
level of the CD player. LIke many recorders of this ilk, the input stage
craps out at a prettly low level. According to the specifications (on the
web site - I guess they were embarrassed to put this in the manual where a
user would find it):

Maximum Input Level at minimum gain +4.3 dBu, balanced

Your "standard" CD player probably has a nominal output level of -10 dBV
at a conservative CD level, with around 16 dB of headroom (-16 dBFS on the
CD gives an output level of =10 dBV). But modern CDs generally run with
the peaks at 0 dBFS. That means that peaks out of your CD player will be
around +6 dBV, which is +8 dBu, 4 dB above the clipping level of your
recorder. Yeah, that really sucks.

What you need is a box with a stereo pot in it so you can turn down the
level of things that don't have an output level control. It's a good
construction project and you can make it with whatever kind of connectors
you think you'll use most. You could use the headphone output of the CD
player - headphone outputs always have a volume control. But you'll need
the appropriate cable and probably adapters.




Thanks Mike.

This is going to be connected to a transformer balanced box fed by a record
output with a volume control, so I see no real difficulties in the field. I
was just testing it out at home first.

It just amazes me that they can label something " Line Level" when clearly
it isn't. Or at least to my understanding of the terminology. Which is you
can connect a CD player to it.



Cheers,


Gareth.

[Geoff]

Gareth Magennis wrote:
It just amazes me that they can label something " Line Level" when
clearly it isn't. Or at least to my understanding of the
terminology. Which is you can connect a CD player to it.

That's more of a loose definition of what is Line Level, rather than a
deficiency in the player or recorder. You've just got to check what each
REALLY mean in their spec.


geoff

[gareth magennis]

"geoff" wrote in message
...
Gareth Magennis wrote:
It just amazes me that they can label something " Line Level" when
clearly it isn't. Or at least to my understanding of the
terminology. Which is you can connect a CD player to it.

That's more of a loose definition of what is Line Level, rather than a
deficiency in the player or recorder. You've just got to check what each
REALLY mean in their spec.


geoff



Umm, well how much variation in output levels is there from your typical
range of CD players? I was of the opinion it was pretty much standardised.



Gareth.

[gareth magennis]

"Soundhaspriority" wrote in message
...

"Gareth Magennis" wrote in message
...
Hi,

just bought the M Audio Microtrack 2 digital recorder. The TRS inputs
are labelled Mic/Line though there doesn't seem to be any switch as such,
just the variable input gain.
Unfortunately there is not enough attenuation available to prevent a
standard CD RCA output from clipping.

This seems very odd. If it is designed for a line input it surely should
be able to cope with a -10dB CD player, but it can't.

Maybe I'm missing something but I can't find a way to turn it down
anywhere.



I've updated to the latest firmware, no difference.


Cheers,



Gareth.
They offer this:
http://www.m-audio.com/products/en_u...ck10dBPad.html

Bob Morein
(310) 237-6511



Thanks, but this looks like it is for the Stereo Mic input. I am using the
TRS Mic/Line inputs and trying to get it to do Line. Unless both these
inputs are essentially the same thing. (?)


Gareth.

[Scott Dorsey]

Gareth Magennis wrote:

Umm, well how much variation in output levels is there from your typical
range of CD players? I was of the opinion it was pretty much standardised.

A whole lot. It is standardized a dozen different ways, which is the problem.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Arny Krueger]

"Gareth Magennis" wrote in
message

just bought the M Audio Microtrack 2 digital recorder. The TRS inputs are
labelled Mic/Line though there doesn't
seem to be any switch as such, just the variable input
gain.

Hmm the original Microtrack had a "L/M/H" input voltage range switch on the
left hand side.

The new one doesn't.

Unfortunately there is not enough attenuation available
to prevent a standard CD RCA output from clipping.

Even with the range switch, the original MT had IME the same problem.


This seems very odd. If it is designed for a line input
it surely should be able to cope with a -10dB CD player,
but it can't.

CD players aren't usually -10. They are more like +8 or +10. IOW, FS =
2.0 or 2.5 volts RMS.


Maybe I'm missing something but I can't find a way to
turn it down anywhere.

I ended up making my own attenuators. 2 chassis-mount RCA jacks, 4 1/8 watt
carbon film resistors, TRS plugs, a little solder, some hot-melt glue and a
little shrink tubing. Since the source impedance of the CD player is not
exactly known, don't obsess too much over the resistor values.

[Geoff]

Arny Krueger wrote:

CD players aren't usually -10. They are more like +8 or +10. IOW,
FS = 2.0 or 2.5 volts RMS.

All my Sonys have a -10dBV output, and a 2V output, each labelled as such.
The 2V output also specifies a 47K load, and is taken from a motorised
pot.

geoff

[Mike Rivers]

On Nov 3, 6:14 pm, "Gareth Magennis"
wrote:

It just amazes me that they can label something " Line Level" when clearly
it isn't. Or at least to my understanding of the terminology. Which is you
can connect a CD player to it.

It amazes me, too. I can understand if it's a bit too close to the
edge, but this isn't even close to what even a "consumer" product can
put out. I guess they keep the price down by leaving out an attenuator
and switch, and leave it up to the customer to supply it himself if he
needs it. The usual excuse is "not everyone needs this so we can same
some users some money."

[Mike Rivers]

On Nov 3, 6:12 pm, "geoff" wrote:

Many players have a nominal ouput of -10dBV, and others have a nominal
output of 2V. Some have both.

... each which I would expect to be the output levels at 0dBFS

Expect whatever you want, but reality is different. Nominal level does
not mean peak level. Nominal level is peak level minus the amount of
headrom that the manufacturer chooses to allow. A "pro" device that
has a nominal input level of +4 dBu had better be able to take peaks
up to at least +20 dBu (+26 dBu is better) without clipping. And if it
has a nominal output level of +4 dBu, it might put out peaks of at
least +20 dBu.

So if that's the kind of output you're dealing with, you'd better have
a similar input to connect it to. Otherwise you run into problems like
Gareth is having. And it's why I have a couple of cables in the pack
with my Zoom H2 that have 15 dB pads built into them so I can connect
it to the output of a console without worrying about the input stage
clipping.

[Mike Rivers]

On Nov 3, 7:00 pm, "Soundhaspriority" wrote:
I would look at the input impedance. Call them if necessary. Line inputs are
typicall 10K-20K. Mike inputs are typically around 1K (though quoted most
often as "compatible with", rather than the true impedance.)

You don't have to call them, it's on the web page. It's about 5K,
which means it's a touch low for your typical line output, and
somewhat high for an SM57, but not bad for a transformerless condenser
mic.

The optimal
resistors in the attenuator would be different for each. If you use the one
I mentioned, it may load down a CD output too much.

A pad with a 10K resistor in series and 1K shunt would be about right
and wouldn't load the CD player too much.

[Arny Krueger]

"geoff" wrote in message

Arny Krueger wrote:

CD players aren't usually -10. They are more like +8
or +10. IOW, FS = 2.0 or 2.5 volts RMS.

All my Sonys have a -10dBV output, and a 2V output, each
labelled as such. The 2V output also specifies a 47K
load, and is taken from a motorised pot.

I have a Sony CD/casette/FM player (no power amps) that is something like
that.

Unfortunately, it isn't what I use my Microtrack with.

I've mostly been using my Microtrack as a safety recorder for a Technics CD
recorder. It has so-called line outputs that are in the 2V class, so my
Microtrack will clip unless I use an external attenuator with it.

[gareth magennis]

"Soundhaspriority" wrote in message
...

"Mike Rivers" wrote in message
...
On Nov 3, 7:00 pm, "Soundhaspriority" wrote:
I would look at the input impedance. Call them if necessary. Line inputs
are
typicall 10K-20K. Mike inputs are typically around 1K (though quoted
most
often as "compatible with", rather than the true impedance.)

You don't have to call them, it's on the web page. It's about 5K,
which means it's a touch low for your typical line output, and
somewhat high for an SM57, but not bad for a transformerless condenser
mic.

The optimal
resistors in the attenuator would be different for each. If you use the
one
I mentioned, it may load down a CD output too much.

A pad with a 10K resistor in series and 1K shunt would be about right
and wouldn't load the CD player too much.


I'll go with that.

Bob Morein
(310) 237-6511


That was going to be my next question



Gareth.

[gareth magennis]

"Scott Dorsey" wrote in message
...
Gareth Magennis wrote:

Umm, well how much variation in output levels is there from your typical
range of CD players? I was of the opinion it was pretty much
standardised.

A whole lot. It is standardized a dozen different ways, which is the
problem.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."



OK, mine is an HHB Burn it. The instruction manual says
"RCA phono output level (0dBFS, 10K load) 9dBu.


Where does that come in the 'how loud is it' list of common fixed output CD
players? I'm guessing on the high side.




Gareth.

[gareth magennis]

"Gareth Magennis" wrote in message
...

"Scott Dorsey" wrote in message
...
Gareth Magennis wrote:

Umm, well how much variation in output levels is there from your typical
range of CD players? I was of the opinion it was pretty much
standardised.

A whole lot. It is standardized a dozen different ways, which is the
problem.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."



OK, mine is an HHB Burn it. The instruction manual says
"RCA phono output level (0dBFS, 10K load) 9dBu.


Where does that come in the 'how loud is it' list of common fixed output
CD players? I'm guessing on the high side.





Sorry, being lazy, thats over 2 volts. How high is a typical cheap domestic
Hi Fi one, that isn't 2 volts then?



Gareth.

[Mike Rivers]

Gareth Magennis wrote:

OK, mine is an HHB Burn it. The instruction manual says
"RCA phono output level (0dBFS, 10K load) 9dBu.

Where does that come in the 'how loud is it' list of common fixed output CD
players? I'm guessing on the high side.

Nope, that's pretty normal, about 2V at maximum output. It's the
equivalent of -10 dBV nominal output level with 16 dB of headroom.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Geoff]

Mike Rivers wrote:
On Nov 3, 6:12 pm, "geoff" wrote:

Many players have a nominal ouput of -10dBV, and others have a
nominal output of 2V. Some have both.

... each which I would expect to be the output levels at 0dBFS

Expect whatever you want, but reality is different. Nominal level does
not mean peak level. Nominal level is peak level minus the amount of
headrom that the manufacturer chooses to allow. A "pro" device that
has a nominal input level of +4 dBu had better be able to take peaks
up to at least +20 dBu (+26 dBu is better) without clipping. And if it
has a nominal output level of +4 dBu, it might put out peaks of at
least +20 dBu.

So if that's the kind of output you're dealing with, you'd better have
a similar input to connect it to. Otherwise you run into problems like
Gareth is having. And it's why I have a couple of cables in the pack
with my Zoom H2 that have 15 dB pads built into them so I can connect
it to the output of a console without worrying about the input stage
clipping.

And that a 'nominal' level, especially on an input is meaningless. A
meaningful spec would be maximum peak input, as it seems everybodys'
'nominal' is different.

How would it be on a digital device that quoted a max output level at some
unknown dBFS ? Totally pointless - the only meaningful spec is max output
level at a specified dBFS.

geoff

[gareth magennis]

"Mike Rivers" wrote in message
...
Gareth Magennis wrote:

OK, mine is an HHB Burn it. The instruction manual says
"RCA phono output level (0dBFS, 10K load) 9dBu.

Where does that come in the 'how loud is it' list of common fixed output
CD players? I'm guessing on the high side.

Nope, that's pretty normal, about 2V at maximum output. It's the
equivalent of -10 dBV nominal output level with 16 dB of headroom.






Hmm, I need to go back and learn my dBs again. I gave away my Yamaha Sound
Reinforcement Handbook to a friend who didn't appreciate it. Damn.


Gareth