Welcome to RO!

This sounds like a problem with what is called gain staging. Put simply, it means adjusting the input and output levels so that a signal passes through without distortion but also with minimal increase in background noise.

Please tell us the make and model numbers of the preamp, compressor and audio interface you are using, and list exactly the inputs and outputs of each that the signal route takes. It would also help to know what the level controls were set to on the preamp and compressor.

I see in his member information that he uses Zoom R24, Presonus Firepod, GT55, Neumann m147 But, doesn't say which preamp and compressor.
Boswell, with a tube mic like the GT55 could it be that the fantom power of certain preamps is not strong enough ?

I guess we'll get a better Idea when knowing what's the make and models... ;)

Boswell, post: 413197, member: 29034 wrote: Welcome to RO!

This sounds like a problem with what is called gain staging. Put simply, it means adjusting the input and output levels so that a signal passes through without distortion but also with minimal increase in background noise.

Please tell us the make and model numbers of the preamp, compressor and audio interface you are using, and list exactly the inputs and outputs of each that the signal route takes. It would also help to know what the level controls were set to on the preamp and compressor.

Appreciate ,Boswell !!

Behringer Ultragain Pro MIC2200
Behringer Composer Pro MDX2200
Presonus Firepod
Zoom R24

Thanks for help!

I guess it may be a wiring or impedance matching problem. You need to match the inputs and outputs to the same nominal level. Check the switches of +4 or -12db behind the Behringer Composer Pro MDX2200.

Thanks for the equipment list, but how did you have them interconnected? Do you get excessive noise if you don't go via the MIC2200 and MDX2200 but plug the microphone directly into the Firepod? Both those other pieces of gear unfortunately are well-known for having high internal noise levels.

pcrecord: the GT55, in common with most tube mics, has its own power supply and therefore does not need phantom power.

pcrecord, post: 413201, member: 46460 wrote: I guess it may be a wiring or impedance matching problem. You need to match the inputs and outputs to the same nominal level. Check the switches of +4 or -12db behind the Behringer Composer Pro MDX2200.

I was using TRS cables for the output, and seemed the switches of +4 or -12db doesn't matter to it?!

Boswell, post: 413202, member: 29034 wrote: Thanks for the equipment list, but how did you have them interconnected? Do you get excessive noise if you don't go via the MIC2200 and MDX2200 but plug the microphone directly into the Firepod? Both those other pieces of gear unfortunately are well-known for having high internal noise levels.

pcrecord: the GT55, in common with most tube mics, has its own power supply and therefore does not need phantom power.

Mic to Preamp to Compressor to Interface, this was the chain.

Many thanks to your kind suggestion and advices!

Ah !! Yes Boswell, I new there was something to them.. (I don't own a tube mic myself)

Mactreouser : the problem you describ is often due to a unit that is sending a faint signal and the next on the chain need to boost it too much.
So I read in the MIC2200 manual the outputs trs and xlr are wired in parallel together. Make sure the balance between the gain and output level is ok. A lot gain and Hi output or a hi gain and low output can result of more noises.
Then in the manual of the mdx2200 it is said nowhere that the TRS are not affected buy the level switch

AUDIO INPUT

Connectors XLR and 1/4" jack
Type RF filtered, servo-balanced input
Impedance 50 kOhm balanced, 25 kOhm unbalanced
Nominal operating level +4 dBu/-10 dBV switchable
Max. input level +21 dBu balanced and unbalanced
CMRR typ. 40 dB, >55 dB @ 1 kHz

So with the switch you change the input value and not the output. If it has no effect for you, you may have used the sidechain input instead of the input called (INPUTS) xlr or trs.

pcrecord, post: 413206, member: 46460 wrote: Ah !! Yes Boswell, I new there was something to them.. (I don't own a tube mic myself)

Mactreouser : the problem you describ is often due to a unit that is sending a faint signal and the next on the chain need to boost it too much.
So I read in the MIC2200 manual the outputs trs and xlr are wired in parallel together. Make sure the balance between the gain and output level is ok. A lot gain and Hi output or a hi gain and low output can result of more noises.
Then in the manual of the mdx2200 it is said nowhere that the TRS are not affected buy the level switch

AUDIO INPUT

Connectors XLR and 1/4" jack
Type RF filtered, servo-balanced input
Impedance 50 kOhm balanced, 25 kOhm unbalanced
Nominal operating level +4 dBu/-10 dBV switchable
Max. input level +21 dBu balanced and unbalanced
CMRR typ. 40 dB, >55 dB @ 1 kHz

So with the switch you change the input value and not the output. If it has no effect for you, you may have used the sidechain input instead of the input called (INPUTS) xlr or trs.

Wow...Really appreciate!!! :D

Thanks for clarified it!

1. I'll try it over again on +4 & -10 soon.
2. Can I have some idea about how to use the sidechain? I would love to do a test drive.
3. C'ld you please share your own experience about how you adjust the right Input and Out level from the Preamp to get the good input level and lowest hiss noise?

Appreciate again! ;)

Mic2200 : First thing, make sure you adjust the mic/line switch to mic and add the 48v only if your mic needs it. deactivate the EQ to start. Sadly, this unit don't have a gain and output seperate meter so you have to guess. start with the output to 0db, put up the gain so the output level peak at -6db
MDX2200 : start with the gate to off and peak limiter to off. Put the output to 0db and put the attack/release to auto. Start with the ratio of 2:1 and the thresold to 0db and while making the source play, lower the thresold until you have a gain reduction of 2-4db. Check the results. Now that your gain stage is nearly standard.. play with the other options to meet your taste !!

Side chain is used to input a second signal into the compressor that will be use to influence the compressor behavior independently of the source who's been compress. Exemple : you could send a guitar to the compressor and a vocal to the sidechain. When the thresold is reached by the vocal, the guitar will be compressed. Hope it is clear enough. More info about sidechain in the manual ;)

Edit : if you send the vocal to the side chain it won't be heard in the output of the compressor, it only serve as a reference for how the compressor will behave on the guitar signal.

pcrecord, post: 413227, member: 46460 wrote: Mic2200 : First thing, make sure you adjust the mic/line switch to mic and add the 48v only if your mic needs it. deactivate the EQ to start. Sadly, this unit don't have a gain and output seperate meter so you have to guess. start with the output to 0db, put up the gain so the output level peak at -6db
MDX2200 : start with the gate to off and peak limiter to off. Put the output to 0db and put the attack/release to auto. Start with the ratio of 2:1 and the thresold to 0db and while making the source play, lower the thresold until you have a gain reduction of 2-4db. Check the results. Now that your gain stage is nearly standard.. play with the other options to meet your taste !!

I'm sorry for my Big + Huge Mistake during the previous recording ~ DID NOT Switch to the MIC (mic/line)!!! :cry: Why I met this big mistake? That's because the indicator diagram showed as "Mic to Release the button", that was what I think of during sound check! So, It supposed Button In for Mic!!!
Today, I check sort this out and pretty nice result I got, finally! Thank you for your precious efforts.

pcrecord, post: 413229, member: 46460 wrote: Side chain is used to input a second signal into the compressor that will be use to influence the compressor behavior independently of the source who's been compress. Exemple : you could send a guitar to the compressor and a vocal to the sidechain. When the thresold is reached by the vocal, the guitar will be compressed. Hope it is clear enough. More info about sidechain in the manual ;)

Edit : if you send the vocal to the side chain it won't be heard in the output of the compressor, it only serve as a reference for how the compressor will behave on the guitar signal.

This is interesting...but i'm not so sure how this works?!! Btw, do we need this setup?

You don't need it. It's an extra feature. What happen is that a compressor monitors the level of the signal you send in the input and if that level is higher than the thresold, the compressor will lower the output level accordingly to the ratio, attack and release. So if we keep our exemple of a guitar in the input of the compressor without side chain ; if you play the guitar at a level that pass the thresold, the output level will be lowered. Now if you add a vocal as a side chain signal. The compresor won't analyse the guitar input anymore, it will react to the level of the vocal. if you sing louder and pass the thresold, the guitar will be lowered. This technic is use for many purpose; if you want to make sure a certain signal will always be louder than an other for exemple...