Using tiny guitar preamp tween external min and dslr

N

neilpollick

New member
There is a tiny portable preamp for guitar that has 20db of gain and runs on a 9v battery (not phantm power, but 3.5" mic such as the specialised vido mics on the market now)
It's this one, Schatten Mini-Pre
http://schattendesign.com/mini-pre.htm
and I am wondering if anyone knows if it could be used to boost the signal from a mono mic before before it goes into the DSLR

Pease dn't tell me it needs adapters, I know (male xlr to female 3.5 mono, and male xlr to 3.5 male)
And please don't tell me that the Rode Videomic pro has built in 20db gain.
And please don't ask me what mic and camera I have.

What's relevant, is if the unit will work and what the noise introduced would be like.
Is the circuitry to boost a guitar signal different from that for a mic?
 
The terse reply frm Mr Jones doesn't give me the information I need, though I am greteful.
His might be an authratiative reply but I do not know him.

So... how exactly, in terms of amplification and noise are the 2 kinds of amps different?

I am sure it would amplify the input, but how would it sound?

Would the boosted signal be too noisy?
Has anyone tried it?
Would it be a waste of money?
(its size is certianly attractive)
 
It's really not worth your time and money, unless you want to amplify a guitar pick-up. Guitar level, line level, and microphone level are different signals.

GJ
 
neilpollick said:
Pease dn't tell me it needs adapters, I know (male xlr to female 3.5 mono, and male xlr to 3.5 male)
Click to expand...

Actually, though they don't really give enough specs for this device, it looks from the pictures like both inputs and outputs are 1/4", not 3.5mm (1/8"). That's to be expected, at least for the input, since pick-ups on most instruments (guitars and the like) use 1/4". Output from the pre-amp on 1/4" is a little odd, though... most guitar pre-amps have XLR output.

Gregg Juke said:
Guitar level, line level, and microphone level are different signals.
Click to expand...

To expand on that:

Line level is either -10dB unbalanced (consumer) or +4dB balanced (professional).
Mic level is generally between -50dB and -60dB.

Instrument level is somewhere in between, but lies closer to line-level. This is the same reason that the 1/4" ins on the Zoom H4n aren't really proper line-level ins, because they are designed for instrument level. Feed them a line-level signal and you overdrive the inputs. Anyway, the +20dB of gain on the Schatten won't be enough to drive a mic up to proper line-level for recording. Get a proper mic pre-amp, not an instrument pre-amp.
 
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The reason I cut to the chase was based on your original post and your list of "please don't tell me's".
So rather than explain the differences between impedances of the signals, connectors, gain structures and the like, I gave you the answer I did. And while it's true you do not know me, I have over 35 years of real world experience in audio/video/film.

All the Best!

Dave
 
Is there an equivalent for DSLR mi?

Is there an equivalent for DSLR mi?

So does anyne know of a tiny single channel battery powered non-phantom-power preamp that would do the job, amplify the signal so that I don't have to use the analogue gain of the camera?
(20db of gain)

I am a truly itinerant filmmaker and the smaller the unit the better.

I's apprecaite any leads.

Thanks.
 
Sound Devices makes a couple of lower cost high quality units that might fit the bill.
They can often be found used for a better price.

As a matter of fact there is a MM-1 for sale in the marketplace forum for $250.

All the Best!

Dave
 
If you want cheap, you can go with a fiio E3. Its a consumer-grade headphone amplifier that I use to boost my monitoring 'phones if using Magic Lantern, since the jack outputs a very low signal from the camera.

It wouldn't be my first suggestion if you were looking for a pro quality microphone amp, but it is capable of do what you are looking for.

The one that David Jones is recommending is without a doubt higher quality, so I would recommend that if you've got the money for it. I have, however, once tried using my fiio on a mic when troubleshooting an audio problem, and it didn't sound half bad to me. But YMMV- not sure if I'd use it on a shoot.
 
M. Gilden said:
If you want cheap, you can go with a fiio E3. Its a consumer-grade headphone amplifier that I use to boost my monitoring 'phones if using Magic Lantern, since the jack outputs a very low signal from the camera.

It wouldn't be my first suggestion if you were looking for a pro quality microphone amp, but it is capable of do what you are looking for.
Click to expand...

I think you misread what he's looking for. He wants a microphone preamp not a head phone amp. The fiio is not at all usable and could be dangerous (to the camera) as a "mic pre".

OP:
Under $100 you pretty much need to make it yourself to get decent quality. In the $100 to $600 range there are a number of good battery powered mic pres and small mixers. The low end probably starts with the battery powered "mixer" Behringer makes/made at around $90.
 
Mic pre-amps have low impedance input design for typically 250-600Ohm mics - they get the output up to line level at (as has been said) consumer or pro level. The guitar pre-amp has a very high (1Meg Ohm) input impedance, which is important for guitars, as lower impedances load the pickups and change the sound to a degree - making them a bit muffled, and even having a muting effect to a tiny degree. They use them because High impedance operation doesn't work well with long guitar cables, and the HF response dies off quickly one you go more than 15-20ft or so with capacitive cable. These gadgets just up the level local to the guitar so you can send it down a long cable unaffacted.

If your mic doesn't provide enough input level for the camera, there are battery operated single channel pre-amps available, but they're as expensive as a small mixer.

If you tell people they cannot ask you questions, then why would they want to take the time to guess what you are doing? What you have is critical information. A mic with 20dB of gain seems a perfect solution - why be so mysterious when you want help. A detailed, comprehensive question produces better quality answers.
 
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