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Title: Line Level Output ?
Post by: John Soltys on March 19, 2014, 10:40:28 AM
Hello,

     I have a question about line level output from an http://alesis.com/samplepad (http://alesis.com/samplepad), and I can not find the answer.

    The problem is when I connect the sampler to the mixing board the level is very low and I have to turn the gain up to 5 O'clock, and the fader is also almost fully up. I have tried different ways to connect it , using a DI box , using a different channel, using the headphone output on the sampler same results. Because of other issues this is the 3 sampler we went through, so I don't think it is faulty. We have played a number of venues with experience sound engineers and they also have the same problem. One did mentioned getting a line level pre-amp.
    I have been trying to find out what the line level voltage and Ohms of this sampler is ( If these are even the correct terms ) I would guess it is -10 Dbu., the website does not have this info. I don't know if that would even help.
    The mixer is a Macki Pro FX 16, I have been using the line level input, on the standard mono channel.
 
    Any help would be greatly appreciated
    Thanks
    John
Title: Re: Line Level Output ?
Post by: TJ (Tom) Cornish on March 19, 2014, 10:47:45 AM
Hello,

     I have a question about line level output from an http://alesis.com/samplepa (http://alesis.com/samplepa), and I can not find the answer.

    The problem is when I connect the sampler to the mixing board the level is very low and I have to turn the gain up to 5 O'clock, and the fader is also almost fully up. I have tried different ways to connect it , using a DI box , using a different channel, using the headphone output on the sampler same results. Because of other issues this is the 3 sampler we went through, so I don't think it is faulty. We have played a number of venues with experience sound engineers and they also have the same problem. One did mentioned getting a line level pre-amp.
    I have been trying to find out what the line level voltage and Ohms of this sampler is ( If these are even the correct terms ) I would guess it is -10 Dbu., the website does not have this info. I don't know if that would even help.
    The mixer is a Macki Pro FX 16, I have been using the line level input, on the standard mono channel.
 
    Any help would be greatly appreciated
    Thanks
    John
Per forum rules, you must change your user name to be your full real name.
Title: Re: Line Level Output ?
Post by: Steve M Smith on March 19, 2014, 11:17:49 AM
Generally:

10 dBV for consumer equipment (0.316 V RMS)
+4 dBu for professional equipment (1.23 V RMS)


Steve.
Title: Re: Line Level Output ?
Post by: Tim McCulloch on March 19, 2014, 11:59:14 AM
What did Alesis say?

The Alesis web site is zero fucking help, but I'd bet that this is a -10dB output, that should still be enough to drive a line input without extreme headamp gain.  I suspect you have a cabling issue or a defective unit.

Also your product link does not work.

Hello,

     I have a question about line level output from an http://alesis.com/samplepa (http://alesis.com/samplepa), and I can not find the answer.

    The problem is when I connect the sampler to the mixing board the level is very low and I have to turn the gain up to 5 O'clock, and the fader is also almost fully up. I have tried different ways to connect it , using a DI box , using a different channel, using the headphone output on the sampler same results. Because of other issues this is the 3 sampler we went through, so I don't think it is faulty. We have played a number of venues with experience sound engineers and they also have the same problem. One did mentioned getting a line level pre-amp.
    I have been trying to find out what the line level voltage and Ohms of this sampler is ( If these are even the correct terms ) I would guess it is -10 Dbu., the website does not have this info. I don't know if that would even help.
    The mixer is a Macki Pro FX 16, I have been using the line level input, on the standard mono channel.
 
    Any help would be greatly appreciated
    Thanks
    John
Title: Re: Line Level Output ?
Post by: John Soltys on March 19, 2014, 12:19:28 PM
What did Alesis say?

The Alesis web site is zero fucking help, but I'd bet that this is a -10dB output, that should still be enough to drive a line input without extreme headamp gain.  I suspect you have a cabling issue or a defective unit.

Also your product link does not work.

Thanks, I fixed the link. I am still waiting a response.
Title: Re: Line Level Output ?
Post by: Brad Weber on March 19, 2014, 12:34:37 PM
Are you using just the "L/MONO" output on the SamplePad or are you doing something like 'Y'ing the "L" and "R" out on the SamplePad into one input on the mixer?  The latter could result in the mixer seeing only the difference between the two channels and thus getting very little signal.
Title: Re: Line Level Output ?
Post by: Robert Weston on March 19, 2014, 03:32:32 PM
Hello,

     I have a question about line level output from an http://alesis.com/samplepad (http://alesis.com/samplepad), and I can not find the answer.

    The problem is when I connect the sampler to the mixing board the level is very low and I have to turn the gain up to 5 O'clock, and the fader is also almost fully up. I have tried different ways to connect it , using a DI box , using a different channel, using the headphone output on the sampler same results. Because of other issues this is the 3 sampler we went through, so I don't think it is faulty. We have played a number of venues with experience sound engineers and they also have the same problem. One did mentioned getting a line level pre-amp.
    I have been trying to find out what the line level voltage and Ohms of this sampler is ( If these are even the correct terms ) I would guess it is -10 Dbu., the website does not have this info. I don't know if that would even help.
    The mixer is a Macki Pro FX 16, I have been using the line level input, on the standard mono channel.
 
    Any help would be greatly appreciated
    Thanks
    John

I've experienced the same issue with my Mackie Pro FX 12.  Any channel on the Mackie with an XLR input won't work for low-level output devices.  Try the Alesis unit in the RCA inputs of your board, or in the phono inputs of the stereo channels on the board (the stereo inputs should be w/out XLRs).  It should work in either one of those inputs.
Title: Re: Line Level Output ?
Post by: Mac Kerr on March 19, 2014, 06:12:32 PM
I've experienced the same issue with my Mackie Pro FX 12.  Any channel on the Mackie with an XLR input won't work for low-level output devices.

Is there a particular reason you say this? The XLR inputs have 20dB more gain than any of the other inputs.

Mac
Title: Re: Line Level Output ?
Post by: Robert Weston on March 19, 2014, 08:54:03 PM
Is there a particular reason you say this? The XLR inputs have 20dB more gain than any of the other inputs.

Mac

It's my experience with those boards and trying to get volume out of low-level devices.  Looks like the OP is using 1/4" outs on the Alesis - and from experience, those don't work much at all with the 1/4" inputs on the mono channels (for the Mackies - not sure about other boards).  The "volume" issue was remedied by using the stereo inputs on the board.
Title: Re: Line Level Output ?
Post by: Mac Kerr on March 19, 2014, 09:08:52 PM
It's my experience with those boards and trying to get volume out of low-level devices.  Looks like the OP is using 1/4" outs on the Alesis - and from experience, those don't work much at all with the 1/4" inputs on the mono channels (for the Mackies - not sure about other boards).  The "volume" issue was remedied by using the stereo inputs on the board.

My question wasn't about the 1/4" ins. The SLR ins have 20dB more gain available than any (and all) the other inputs on the console, which are all the same gain.

Mac
Title: Re: Line Level Output ?
Post by: Robert Weston on March 19, 2014, 09:21:09 PM
My question wasn't about the 1/4" ins. The SLR ins have 20dB more gain available than any (and all) the other inputs on the console, which are all the same gain.

Mac

I don't doubt you.  If you have access to a Mackie Pro FX board, connect a low level output device to any of the 1/4" inputs on the mono channels.  It barely works... but move the low level device over to a stereo channel and it works exponentially better.
Title: Re: Line Level Output ?
Post by: duane massey on March 19, 2014, 09:37:23 PM
Many, many keyboards have weak outputs. I basically had to get past my uneasiness in regards to the input gain settings and just turn up the channel gain until I had enough signal thru the mixer. The challenge with using a 1/4" unbalanced cable to XLR for me concerns phantom power. If your mixer only has global phantom and you need to use it it can cause problems with some keyboards (if not all?). Ah, the joys of real-world audio.....
Title: Re: Line Level Output ?
Post by: Craig Hamilton on March 19, 2014, 11:48:48 PM
I don't doubt you.  If you have access to a Mackie Pro FX board, connect a low level output device to any of the 1/4" inputs on the mono channels.  It barely works... but move the low level device over to a stereo channel and it works exponentially better.

I believe the adjustable gain has a greater range on the mono 1/4" versus the stereo channels.
Title: Re: Line Level Output ?
Post by: John Soltys on March 20, 2014, 10:10:07 AM
I will not pretend to know much about this. I was looking at the block diagram for the Mackie Pro-FX and it seems that the stereo inputs do have a different input levels and gain structure ( if that is the right term )
Thanks for your help with this.
Title: Re: Line Level Output ?
Post by: Brian Jojade on March 20, 2014, 10:57:33 AM
According to that diagram, using the stereo inputs would give you 10db LESS gain available on the line inputs.

If the output isn't strong enough from the unit, using a 1/4" to XLR adaptor will give you access to 20db more gain.  As long as the audio is clean, this should solve your problem.
Title: Re: Line Level Output ?
Post by: Tim McCulloch on March 20, 2014, 04:35:13 PM
I will not pretend to know much about this. I was looking at the block diagram for the Mackie Pro-FX and it seems that the stereo inputs do have a different input levels and gain structure ( if that is the right term )
Thanks for your help with this.

I'm going to play my Dick Rees card:  you have a fucked up cable or connection.  There is no other technical reason that this device can drive mixers at sufficient level but not when using your cabling and accessories.
Title: Re: Line Level Output ?
Post by: g'bye, Dick Rees on March 20, 2014, 04:48:35 PM
I'm going to play my Dick Rees card:

Tim...

Dick Rees card licenses can be purchased at my iToldUSo shop.  Please contact me to make arrangements.
Title: Re: Line Level Output ?
Post by: Ray Aberle on March 20, 2014, 05:22:12 PM
Tim...

Dick Rees card licenses can be purchased at my iToldUSo shop.  Please contact me to make arrangements.
Awww, come on, tell us what we want to hear... :-p
Title: Re: Line Level Output ?
Post by: Mark McFarlane on March 20, 2014, 05:35:15 PM
According to that diagram, using the stereo inputs would give you 10db LESS gain available on the line inputs.

If the output isn't strong enough from the unit, using a 1/4" to XLR adaptor will give you access to 20db more gain.  As long as the audio is clean, this should solve your problem.


As Duane said previously, a TS to XLR cable may create a new, more serious (permanent) problem if global phantom power is turned on.  Or not.  Perhaps a 1:1 transformer would be safer, albeit more expensive. 


You could test with a 1/4 TS to XLR adaptor with phantom off to see if you solve the gain problem, if so look at a transformer or some other way to stop the phantom from going into the output of your keyboard.
Title: Re: Line Level Output ?
Post by: Steve M Smith on March 20, 2014, 05:38:04 PM

As Duane said previously, a TS to XLR cable may create a new, more serious (permanent) problem if global phantom power is turned on.  Or not.  Perhaps a 1:1 transformer would be safer, albeit more expensive. 

Or a 10uF capacitor. Even cheaper.


Steve,
Title: Re: Line Level Output ?
Post by: Mac Kerr on March 20, 2014, 05:57:20 PM
Or a 10uF capacitor. Even cheaper.

Or use STP and wire tip to of the 1/4" to pin 2, and sleeve to pin 3. Leave shield .connected to pin 1 at XLR only. Rane note 110 fig 17 (http://www.rane.com/note110.html). There is no voltage across pins 2 and 3.

Mac