Looking to buy my first Audio mixer:

[Simon Zimmer]

Hello,

I am researching on which audio field mixer I should buy.

I do videos with my Panasonic HMC-150. I have two mics:

Countryman B3 - omnidirectional (lav mic)
Sennheiser EW112-p G3 (wireless lav mic)

Though I like my HMC-150 a lot, I was never very impressed with the sound quality. The interviews and narrations I do had average sound but I want to take it to the next level.

After reading "The Shut Up and Shoot Documentary Guide", I quickly learned that having a good audio mixer is essential to getting good quality sound.

So after reading various forums, everyone seems to love the SoundDevices Mixer 302. At $1300 it is a lot of money. It is in my budget but I want to make sure it will make the big difference even with my average mics that I own.

If there is a better mixer out there for an audio beginner like me, I would love to hear some suggestions.

thanks,

Simon

[Steve House]

How much of a difference you will notice depends on a lot of factors ... getting top-notch sound depends as much, if not more, on technique as it does on the hardware you use. But you will get more control by using a mixer such as the SD302 and the Sound Devices line is absolutly top quality. True it is a bit priicey but a mixer is a long term invenstment and one such as the SD will last you through a number of new camera iterations. The SD mixers in particular tend to hold their value and a well-treated used one will still sell for close to its original new price. Getting 'the right stuff' at the very start iinstead of buying cheap and upgrading later is actally the least expensive way to go in the long run.

I notice you said "interviews and narration." Lavs are good for field use for interviews but they're not the end-all and be-all. Boom mics where practical are often better sounding in an interview situation. Narration, OTOH, is usually best done in a more controlled studio setting using a dynamic announcer's mic or large-diaphram condensor mic. Different tasks, different objectives, different tools.

[Simon Zimmer]

Hi Steve,

I wrote you on the other forum. ;)

I appreciate the advice. Could you recommend a good narration microphone (dynamic announcer's mic or large-diaphram condensor mic)?

Thanks,

Simon

[Steve House]

There's a bunch at a variety of budget points. Some that come immediately to mind, in no particular order, would include the Electrovoice RE-20 or RE-27 (staples in virtually every radio station in North America), the Shure SM7, Rode NT-1a or NT-2, Rode Procaster, Neumann TLM103 or U87Ai, AKG C414 or C214, and there's a number of others.

[Bill Wilson]

There is a new item to consider when buying a mixer. Most of the mikes coming from the far east, especially all varieties of condenser mikes specify a minimum load impedance of approx. 1400 ohms.

Sound devices mixers use Lundahl input transformers on the mike inputs; what they do not state is the impedance of the primary winding of the transformers. Most mixers using input transformers have an impedance of 200 ohms on the primary winding, this is too low for many of the inexpensive condenser mikes & can result in loading induced distortion. The way to avoid this is to use a mixer that has electronically balanced mike inputs, as these typically have an input impedance of 2000 ohms or higher.
These electronically balanced inputs using high quality chips specifically designed as balanced mike preamps will have cleaner sound & lower distortion as opposed to a transformer coupled input.

[Claire Buckley]

Bill speaks very good words of wisdom. I would have put his post in quotes but VBulletin seems like it doesn't give this option for the last repsonse - no matter.

Unless you wish to struggle with f-response down to near dc levels in terms of audio with metal iron core principles or wish to isolate your feeds from some possible electrical "nasties" then why ask for a transformer coupled mic input device with the added weight, space and expense.

But let us not forget that input transformer coupling of 1:3 also provides cheap voltage gain at the expense of front-end analogue amplifier noise. But heck, that's analogue talk for you, before A-to-D conversion.

"Using high quality chips..."

Gone are the days you will see a transformer-coupled quasi hi-impedance bootstrap analgue font-end. But if you look carefully, you might find...

:)

[Steve House]

Originally Posted by Bill Wilson

There is a new item to consider when buying a mixer. Most of the mikes coming from the far east, especially all varieties of condenser mikes specify a minimum load impedance of approx. 1400 ohms.

Sound devices mixers use Lundahl input transformers on the mike inputs; what they do not state is the impedance of the primary winding of the transformers. Most mixers using input transformers have an impedance of 200 ohms on the primary winding, this is too low for many of the inexpensive condenser mikes & can result in loading induced distortion. The way to avoid this is to use a mixer that has electronically balanced mike inputs, as these typically have an input impedance of 2000 ohms or higher.
These electronically balanced inputs using high quality chips specifically designed as balanced mike preamps will have cleaner sound & lower distortion as opposed to a transformer coupled input.

Sound Devices published specs for all of their mixers state their mic inputs have actual impedances of 2k ohm or greater. (MixPre - 2k; 302 - 2.6k; 552 - 2k)