[marsx]

Hi,

I have read that the signal from a microphone degrades after about 20 feet on various forums.  When people say this are they refering to the whole microphone signal chain (mic to preamp to audio card) or are they just talking about the distance from the mic to the preamp?

Secondly, if it is just to the preamp, is there a rule of thumb in the studio about how long the whole signal chain can be from mic to preamp to audio card before degradation or interference may cause a problem.  This is assuming all cable is high end Mogami cable and all equipment in chain is balanced.

Any responses will be greatly appreciated.

Sincerely,
marsx

[JackD201]

Rule of thumb is 20ft optimum for XLR but ok up to 100ft before things get really hairy

For Tuchel it's about 33ft then 200ft.

Curiously single ended is okay to 150ft even for AES3 digital but the tradeoff is increased risk of interference.

[gerald porzio]

In sound reinforcement, runs exceeding 200 ft are common. There are many other more important variables like the quality of the preamps & mics. The entire world does not possess the audiophile fetish for cables.

[JackD201]

In sound reinforcement, runs exceeding 200 ft are common. There are many other more important variables like the quality of the preamps & mics. The entire world does not possess the audiophile fetish for cables.

Very true

[Wind Chaser]

The entire world does not possess the audiophile fetish for cables.

Perhaps that is a symptom of why there are so many 'average' recordings of great music??

[gerald porzio]

The reason is average engineers compensating for mediocre talent.

[Dan Banquer]

Hi,

I have read that the signal from a microphone degrades after about 20 feet on various forums.  When people say this are they refering to the whole microphone signal chain (mic to preamp to audio card) or are they just talking about the distance from the mic to the preamp?

Secondly, if it is just to the preamp, is there a rule of thumb in the studio about how long the whole signal chain can be from mic to preamp to audio card before degradation or interference may cause a problem.  This is assuming all cable is high end Mogami cable and all equipment in chain is balanced.

Any responses will be greatly appreciated.

Sincerely,
marsx

From what I understand this will be very dependent on the output impedance of the microphone. A high output impedance mic will need a short cable run if you wish to maintain a full frequency response. I would recommend checking the spec's in this area on the microphones used and possibly consulting with the manufacuturer for the desired results.
Regards;
  Dan Banquer
P.S. Ping Russ Dawkins, he may be a good resource here.

[JackD201]

Perhaps that is a symptom of why there are so many 'average' recordings of great music??

I think the reason is producers gearing recordings for the most common playback platform the last two decades.......radio play in cars.

Now that earphones mated with portable devices are coming up quick, I'm hoping this will change for the better. Certainly there will be less need for dynamic compression.

[JimJ]

The reason is average engineers compensating for mediocre talent.

Even some very talented artists have been putting out awful recordings.

Perhaps that is a symptom of why there are so many 'average' recordings of great music??

Believe me, I'd love it if we could mark up runs of 16/2 like that

[Wind Chaser]

IMO, the mass of recorded music has always been average… at best.  And those specialty labels that put the extra effort into making a great recording do so with less than average music that the average person doesn't particularly care for.  I’ve spent way too much money for expensive recordings of complete crap music only for the sake of ‘high fidelity’.

[JimJ]

I'll agree with that. No point in listening to something that's "technically" amazing if you can't get into the music.

[*Scotty*]

There is a Holt's Law concerning the recording quality vs.content phenomena.This law states that, “The better the performance, the worse the recording will be, or conversely, the better the recording sounds, the worse the performance will be.
This has happened often enough that I count the statement as a truism.
Scotty

[Speedskater]

Some very well thought of classical recordings have used mic cables that were 200 feet to 300 feet long. Remember the first stage of the mic pre-amp is inside the microphone.

[pjchappy]

A high output impedance mic is also more prone to pick-up RFI.  I have personally experienced this with just 10 and 15 foot lenghts of Nogami Gold XLR cables going into a high impedance input of my microphone pre-amp.  I think my home studio is some weird RFI magnet, however. . . as I also pick up RFI with my bass guitar directly into a computer interface and with 2 different electric guitars through my pedal board.  Same radio station every time. 


Paul

[Dan Banquer]

A high output impedance mic is also more prone to pick-up RFI.  I have personally experienced this with just 10 and 15 foot lenghts of Nogami Gold XLR cables going into a high impedance input of my microphone pre-amp.  I think my home studio is some weird RFI magnet, however. . . as I also pick up RFI with my bass guitar directly into a computer interface and with 2 different electric guitars through my pedal board.  Same radio station every time. 


Paul

Sounds more like a grounding/shielding problem to me.
Regards;
  Dan Banquer

[pjchappy]

Sounds more like a grounding/shielding problem to me.
Regards;
  Dan Banquer

I have thought the same thing, but it does happen with totally different equipment.  I have tested the ground on the outlets and the little tester indicates they are all properly grounded.  I have used different cables.  They are all (supposedly) well made, shielded and highly regarded.  (Nogami XLRs and DiMarzio guitar cables / patch cables)  Any ideas?  Please post them here:  http://www.audiocircle.com/index.php?topic=72447.20

Don't mean to hijack this thread. . . regardless of my problems, I have read high impedance microphones are more prone to RFI. 

Thanks,


Paul

[Dan Banquer]

I have thought the same thing, but it does happen with totally different equipment.  I have tested the ground on the outlets and the little tester indicates they are all properly grounded.  I have used different cables.  They are all (supposedly) well made, shielded and highly regarded.  (Nogami XLRs and DiMarzio guitar cables / patch cables)  Any ideas?  Please post them here:  http://www.audiocircle.com/index.php?topic=72447.20

Don't mean to hijack this thread. . . regardless of my problems, I have read high impedance microphones are more prone to RFI. 

Thanks,


Paul

Sorry, I should have been more specific: Check the grounding inside the microphone and mic pre amp.
Regards;
   Dan Banquer

[pjchappy]

Sorry, I should have been more specific: Check the grounding inside the microphone and mic pre amp.
Regards;
   Dan Banquer

Thanks.  The microphone RFI is minimal and is only noticeable if I crank the adjustable impedance adjustment on the pre-amp input fairly high.  Happens with 2 different mics; 3 different cables; and 2 different pre-amps, so I would think that would rule out any wiring / grounding issues.  I can also move the cable to certain spots to avoid it when it does happen.

Now. . .if you have any ideas to the other issues in my link above, that would be great!   

Thanks again!


Paul

[Dan Banquer]

"Thanks.  The microphone RFI is minimal and is only noticeable if I crank the adjustable impedance adjustment on the pre-amp input fairly high.  Happens with 2 different mics; 3 different cables; and 2 different pre-amps, so I would think that would rule out any wiring / grounding issues.  I can also move the cable to certain spots to avoid it when it does happen."

I was referring to the grounding inside the microphon(s) (especially the microphone) and mic pre amp(s). Again I shlould apologize for not being more specific.
To sum it up, you shouldn't be getting any RF pick up if the equipment is grounded correctly internally.
Regards;
   Dan Banquer

[pjchappy]

"Thanks.  The microphone RFI is minimal and is only noticeable if I crank the adjustable impedance adjustment on the pre-amp input fairly high.  Happens with 2 different mics; 3 different cables; and 2 different pre-amps, so I would think that would rule out any wiring / grounding issues.  I can also move the cable to certain spots to avoid it when it does happen."

I was referring to the grounding inside the microphon(s) (especially the microphone) and mic pre amp(s). Again I shlould apologize for not being more specific.
To sum it up, you shouldn't be getting any RF pick up if the equipment is grounded correctly internally.
Regards;
   Dan Banquer

Dan,

I understand that.  I am just saying I would think trying 2 different microphones in combination with 2 different pre-amps would rule out any faulty wiring.  Additionally, I have RFI issues with other equipment, which also leads me to believe there isn't any faulty wiring.  Not saying it's impossible, but to me, it seems unlikely.  Regardless, I want to get rid of this. . .

I kinda have hijacked this thread now.  Sorry. . .   


Paul