API 3124 attenuation mod?

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volta

Well-known member
Joined
Dec 10, 2004
Messages
118
API makes a great product but I keep having the same problem with the API 3124.
Drums sound great through the API 3124 but the output level is just too damn hot!

You can turn down the input level through Pro Tools.But why should you have to do that?
Even using a dynamic mic like the sm57 or beta 52 on the 3124 gives you an output that is too hot to use even if you have the pad on.

Has anyone had this problem?If so how have you overcome this delema?

The input of the 3124 is not showing saturation or clipping but the output is too much.
I have a few hot mic pre's at my disposal and they don't give me the same problem as the 3124.
Playing softer is out of the question!
Rock your nuts off!
Mods change sound.
I would like to overcome this problem with not much,or no change to the sound of this unit.
 
I have used the 3124 Before and never had a problem going into pro tools. Mind you it was a TDM system(HD). You should be fine by using the pad on the API and if thats not enough buy an extra pad. Most companies make a pad you can plug inbetween mic and pre. usually a 20 DB pad.
Secondly inrefering to lowing input into protools, do you mean you want recalibrate what level DBFS will be 0 VU or do you mean lowing the fader in pro tools. Lowing the fader on a record ready track in pro tools will effect the monitor and not input level to track unless you are making a split style mixer where one track is input going to a buss going to another track in record to pro tools. OR do you mean lowing the line in pot on like a 002/oo1. I am confused.
 
You could try NewYorkDave's simple volume control hanging off the transformer secondaries. I've not tried it yet, but will.

volumecontrol.gif


Here's something from Paul Wolff.

"I have found that doing 2 things make the 3124 interesting. Take a 5K linear pot and hook it in series with a 1K resistor. Put that accross the output and you can adjust the tone by varying the load. You can also hook a 5K audio taper pot to the output and use it for a trim. The 7600 has the output control, but it is a lot for just a pot..."
 
Sounds interesting.Please let us know how it sounds.I don't have the unit to try the mod on hand right now.
 
[quote author="volta"] .. You can turn down the input level through Pro Tools.But why should you have to do that? [/quote]
what ? :?

does it clip the input of the interface ?
you can always use an in-line pad.
This will leave even more headroom in the mic pre. I'm convinced this is where people have trouble with other mic-pres with less headroom.

... like 2017 and 2019 styled units. I set my pres up so that even when PT clips and gives a red light I know I still have a few dbs of headroom left in the mic-pre.

The interface/matching schem above or similar is a must for all people with digital interfaces ... and line drivers to gain make up when needed.
Many units have the grunt to clip the inputs of interfaces like those from Digidesign (MOA)

You turn levels down inside PT during playback .. because that's called mixing. :wink:
 
Hey,

Slightly silly question... Have you tried recalibrating the input to Tools?? All of the pro Digidesign interfaces i.e 888's & 192's have analogue gain trims. If you're having problems with headroom try setting them up at -18 rather than -14. What are they calibrated at? Or is this a 001 or 002? I think those are set at the factory :mad:

Justin.
 
[quote author="peter purpose"]

Take a 5K linear pot and hook it in series with a 1K resistor. Put that accross the output and you can adjust the tone by varying the load. You can also hook a 5K audio taper pot to the output and use it for a trim. The 7600 has the output control, but it is a lot for just a pot..."[/quote]

When you say across the output? I am confused how this would work since the output is balanced. Maybe I am not understanding.

Also, the picture bove with the 10k pot, won't that srew with the common mode rejection and output impendance?

d./
 
[quote author="thedug"]When you say across the output? [/quote]

I didn't say that, Paul Wolff said that. As for Dave's drawing... yes I do believe that impedance is moved around somewhat, but I'm not qualified to comment.
 
[quote author="thedug"] ... When you say across the output? I am confused how this would work since the output is balanced.
... Also, the picture bove with the 10k pot, won't that srew with the common mode rejection and output impendance? [/quote]

to both questions,
the signal will still have a balanced quality to it if the next input stage is floating differential.
The potential volts across the Pot and resistor combo is what the next section will see. CMR will still work.

Yes it does change the impedance the driving unit sees. By loading the driving output you can change it's tone. It's up to you how far you take that and will depend much on the nature of the output trafo.


Justin,
... recalibrating the input to Tools (not sure the 96 can) will only change were you have you 0dbv-0dbu set at -14 -18 or -20 (ala Sony).

This will still not help if the level going into the first analog stage is just TOO hot.
There will always be a unit out there that just has so much level to clip ... no mater how much headroom you give a unit.
Modern gear is lower than some of the gear of the past.
 
[quote author="peter purpose"]Here's something from Paul Wolff.

"I have found that doing 2 things make the 3124 interesting. Take a 5K linear pot and hook it in series with a 1K resistor. Put that accross the output and you can adjust the tone by varying the load. You can also hook a 5K audio taper pot to the output and use it for a trim. The 7600 has the output control, but it is a lot for just a pot..."[/quote]

What d you mean "accross the output"?

i.e.

(+) --- 5k -- 1 -- (-)

???
 
My solution is simple.
Solves the problem once and for all.
Throw the Pro Tools system away.

If you cannot do that use the pad
peter purpose suggested above.
Once you find the correct resistor value with the pot
replace the pot with a fixed resistor.
 
[quote author="thedug"]What d you mean "accross the output"???[/quote]Across the output transformer's secondary which should go to pins 2 and 3.
 
[quote author="adrianh"] ... Throw the Pro Tools system away. [/quote]

:roll:
nah
it aint gonna happen

It is my cheapest, most reliable and most useful option to recording.
....
and I'm not going to stop using MS Word or Excel ... or Outlook and IE
...
or FCP
...
or any other pakage or hardware combination that allows my to get a project done and on budget and with in the law.
...
yes I am prepared to use some older out of support software that is no longer available for purchase.

:cool:
 

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