Tech/maintenance Fethead inline amplifier

Gallen · Sep 10, 2011

Hey all!
I'd like to share my experiences with Triton Audio's fethead inline amplifier. Took about a week to arrive from the netherlands. It's basically a phantom powered amplifier connected in between the mic and preamp. In my case, what I do have is a Shure SM57 connected to my Onyx Blackjack usb audio interface.

The issue I've encountered is that when I'm miking further, even at the full gain of 60, the volume levels are not very hot. Read about the fethead on the usual recording websites and thought it'd be a nice thing to get nice clean gain boost at an affordable price.

Tested on two sets of audio signals, my alto sax and my voice.

Here's the recordings listed out in audacity attached. The saxophone recorded without the fethead at a distance gives not as hot a signal - but with the fethead, even with a gain of 30 it's giving quite a boost.

Here are some audio samples:

DeadAudiolink Removed (Saxophone with fethead, gain 35)
DeadAudiolink Removed (Saxophone, no fethead, gain 60 - sadly soundcloud automatically normalized the gain)

DeadAudiolink Removed (Vocals with fethead, gain 45)
DeadAudiolink Removed (Vocals no fethead, gain 60)

I bought the fethead with my own £££ and I do think it does make an interesting change to my saxophone's sound, seems to give it more body and less whine, less airy. Note that this is mainly designed for dynamic mics.

HTHs!

EDIT: I just listened through my laptop's speakers, can't tell much of a difference. The difference is there on my AKG 240MKIIs via the audio interface.

Chris · Sep 10, 2011

Hey Gallen, it does fatten up your sound a lot, the speakers this side are BX5a's from M-Audio 75w. It sounds good.

Chris

Gallen · Sep 10, 2011

Hey Chris, thanks for confirming the sound improvement 🙂 I read that they work really well on ribbons too. Man, would love a ribbon mic.... 🙂 Have a good weekend 🙂

Nick Wyver · Sep 11, 2011

What's it actually for? You shouldn't have gain problems with a 57.

Gallen · Sep 11, 2011

Hi Nick!
The fethead is supposed to give 20db of gain and perform impedance matching. The 57 with my preamps at full gain doesn't give much signal when I'm far micing the sax though....

Nick Wyver · Sep 11, 2011

Well, having just looked at the spec on the Onyx Blackjack, I wouldn't have thought you would need anything else. When you say far miking, exactly how far do you mean?

Gallen · Sep 11, 2011

Hi Nick, about ~2 feet away from the middle of the stack?

Nick Wyver · Sep 11, 2011

Blimey. If you can't get it to clip at that sort of distance I'd be inclined to check how it's set up.

Gallen · Sep 11, 2011

Hmmm I was thinking about volume, pretty sure I got a good signal level when playing at full volume, with the mic at a further distance. However for the ones I recorded above, I was at... mf, f maybe. Perhaps that?

Young Col · Sep 12, 2011

What you've done is OK for what you want but the real problem is that at two feet away you are going to lose a lot of sensitivity with an SM57 dynamic. You really need to be much closer in with a dynamic and the SM57 gets warmer as you get closer to the source, although some people think the SM57 has too much top response for an alto sax anyway. The reason it sounds different with the Fathead is because it is boosting ambience. Have you experimented with closer miking as that's how the SM57 is designed to be used and performs best? Two feet is too far to be effective. A mic like a Sennheiser MD421 would give you a less poppy, warmer sound.
YC

Gallen · Sep 12, 2011

Hi YC, I have experimented in the past with closer micing but I don't think I got very good results, the one with the fethead is probably my favourite so far, but I will give it another go. In your experience, what position is good for the SM57?

Also, with regards to micing about 2 feet away, I was following this example on youtube - my mic was further away though, roughly at the height of the crook pointing down. Would a condenser work better for micing at a distance?

Young Col · Sep 12, 2011

Hi Gallen
Best position for an SM57 is going to be within a max of 8-12 inches from the bell, but don't be afraid to put it too close. It will take all you give it.
The example you linked to is actually using two condenser mics. There's a main one which is at most a foot away from the sax and the secondary one is to the side (almost obscured by the sax). The secondary one will give a bit of natural reverb. The example of using a condenser mic applied to a dynamic mic is not a good analogy!
Hope that helps!
YC