Model 2400 line stereo metering

[Gtrscot]

I recently purchased a Model 2400 and it is excellent, however I have noticed while using the Ch 19/20 21/22 input's to connect a CD player, set to line to monitor that the stereo metering on the master Ch is not metering evenly each side. Both sets of inputs do the same thing but in reverse in that the left LED's are lower than the right and vice versa. This follows through to my external speaker controller that has independent metering..
I have a pro CD player with XLR outputs and using identical XLR to TRS to connect into the console. Same thing happens using standard RCA to RCA with TS adapter.
Has anyone else come across this or am I doing something wrong?

 

[Mark Richards]

...Model 2400...using the Ch 19/20 21/22 input's to connect a CD player, set to line the stereo metering on the master Ch is not metering evenly each side. I have a pro CD player with XLR outputs and using identical XLR to TRS to connect into the console. Same thing happens using standard RCA to RCA with TS adapter.

Welcome to the forum @Gtrscot.

Has anyone else come across this

Not so far

am I doing something wrong?

Probably.

I'm not a user of the Model 2400, so I'm referring to the OM to try and help.

Let's start by providing some basic info:
* Does your pro CD player have a seperate XLR output jack for each side (L/R) of the stereo signal?
* Does your pro CD player have TS RCA ouput jacks ifor each side (L/R) of the stereo signal?
* Does your pro CD player output at -10dBu or +4dBu for the XLR stereo out circuit
* Does you pro CD player output at -10dBu or +4dBu for the TS RCA stereo out circuit?
* What's the output impedance of the pro CD player's stereo line out circuit: for XLR; for RCA?

* The model 2400's Channel 19/20 is a balanced combo jack (XLR/TRS/L) and a balanced TRS jack (R) stereo circuit. How are you connecting the stereo out of the CD player to the Channel 19/20 stereo circuit? Please be precise for each side of the stereo signal.

* The model 2400's Channel 21/22 has two balanced TRS inputs: One each for the L/R stereo signal respectively. How are you connecting the stereo out of the CD player to Channel 21/22? Please be precise for each side (L/R) of the stereo signal.

Precise answers to the above will give us a useful starting point without having to make guesses or assumptions that may not be valid.

 

[-mjk-]

This follows through to my external speaker controller that has independent metering.

I think this means that your outboard monitor controller confirms the stereo spread on the meters. Is that right?

How does it sound? Does the sound match the metering?

 

[Gtrscot]

Thanks for the response.
Note: This issue does not appear on inputs 17/18. That works as I believe it should.
I have a Tascam CD-450 player

* Does your pro CD player have a seperate XLR output jack for each side (L/R) of the stereo signal? Yes
* Does your pro CD player have TS RCA ouput jacks ifor each side (L/R) of the stereo signal? Yes
* Does your pro CD player output at -10dBu or +4dBu for the XLR stereo out circuit. Need to research
* Does you pro CD player output at -10dBu or +4dBu for the TS RCA stereo out circuit? Need to research
* What's the output impedance of the pro CD player's stereo line out circuit: for XLR; for RCA? I would imagine -10db

* The model 2400's Channel 19/20 is a balanced combo jack (XLR/TRS/L) and a balanced TRS jack (R) stereo circuit. How are you connecting the stereo out of the CD player to the Channel 19/20 stereo circuit? Please be precise for each side of the stereo signal. I am using identical XLR to TRS to connect into the console

* The model 2400's Channel 21/22 has two balanced TRS inputs: One each for the L/R stereo signal respectively. How are you connecting the stereo out of the CD player to Channel 21/22? Please be precise for each side (L/R) of the stereo signal. I am using identical XLR to TRS to connect into the console

 

[Max Relic]

Link to the Tascam CD-450 owner's manual

@Mark Richards , @Gtrscot , Nominal output level is -10dBv / 10kOhm for RCA (unbalanced) and +4dBu / 10kOhm for XLR (balanced). It seems a pretty advanced CD player with uncommon features as adjustable pitch and external play control from a fader or a short pulse.

To the topic: to verify a suspect unbalance between left and right channel, a reference test signal has to be injected in both input channels and the output signal should be measured with a reliable meter. A music program is far from being a reference signal unless a test CD* is played, and the player has no unbalance between channels.

* A test CD can easily be home made by burning a reference wave signal created with any audio editor software or DAW, or downloading some free wave files from the web.

 

[Gtrscot]

Thanks for the advice Max
Some great suggestions to follow.
I will try a few more things in coming days to qualify ch 19/20, 21/22 channels.
As I mentioned previously, ch 15/16, 17/18 do not present the issue using same connection so logically the problem should follow if it’s a CD player fault. Also 19/20 is metering strangely in the opposite ch of what 21/22 is so certainly some anomalies happening. Same anomaly but different side..

 

[Mark Richards]

@Gtrscot, you could well be right, but I agree with Max that trouble shooting is a process of elimination not based on assumptions but rather on confirmed information. So proceeding slowly is, IMO, the best course of action.

 

[Gtrscot]

I think this means that your outboard monitor controller confirms the stereo spread on the meters. Is that right?

How does it sound? Does the sound match the metering?

Im not sure if I can notice the level difference. It’s not obvious but the fact I can see a difference plays with my OCD I guess I use metering a lot so it makes me question what is happening..

 

[-mjk-]

You're not wrong to question the issue if the metering is real. I spent considerable time working on having an absolutely balanced monitoring system (using white noise cancelling for a test bed). But I have seen devices that did display incorrect metering when my ears told me everything was fine. If you can't hear the difference (and your monitors are balanced) then you are probably ok. If you have doubts about something like the balance in a mix you can post the file and let us analyze it for you.

 

[Gtrscot]

Thanks to all.
I can confirm that putting white noise signal at 1Hz on ch 15/16, 17/18, 19/20, 21/22 all provided identical equal levels.
Need to now try another CD player and see if that is the cause.. although still find it strange CD player was not fluctuating on ch 15/16, 17/18..
Regardless I feel much better knowing the 2400 isn’t faulty as it is the centre piece of my studio and enjoying very much