A clever way to protect your delicate ribbon mics and get a lot more clean gain!
One of the greatest fears I’ve experienced since owning my first ribbon mics, is accidentally destroying them by switching 48v phantom power on whilst having a ribbon mic connected to a preamp. It might sound like a ridiculous mistake but on many interfaces the phantom power switch can be located right next to the phase reverse or HPF switches, making an accident like this not outside the realm of possibility. And that’s not to mention other interfaces and mixing consoles that have the dreaded option of universal phantom power, with one switch for multiple channels of 48v.
Well thankfully, the latest DIY kit from Bumblebee Pro, the BB-P26 Ribbon Mic Booster offers a great solution. The BB-P26 Mic Booster gives you more gain, which can be helpful for people with cheaper interfaces and preamps or when placing a microphone in front of quieter sound sources. As an added benefit however, it is phantom powered which means it will soak up any ribbon destroying 48v in your signal path before it gets to the microphone. How does it accomplish all this? Let’s break it down.
Why do I need a Mic Booster?
Ribbon microphones, by design have a low output signal and need a lot of gain at the preamp especially when recording quieter sound sources like acoustic guitars. This isn’t much of a problem in studios that have expensive preamps like Neve or SSL’s or any other pro studio equipment. But for those of us in the project or home studio environment might find that some of our usb interfaces or preamps don’t quite offer enough gain. How do we get more gain, that is clean and noise free? A Mic Booster, also known as a “cloud lifter” will certainly do the trick. It kind of works like a DI Box, but in reverse. Where a DI Box takes an instrument level signal and lowers that signal to a Mic level, a Mic Booster can take the signal from a Ribbon or even a Dynamic mic and boost that signal BEFORE it gets to the preamp. The only trick is that the signal must be increased without adding any extra noise, otherwise it defeats the whole purpose. The BB-P26 Mic Booster certainly achieves this, whilst retaining the integrity of the original signal.
The Kit
Artur Fisher and the team at Bumblebee Pro state that;
“The Bumblebee Bb-P26 features fully balanced circuitry resulting in a near-perfect EMI immunity, as if your microphone cable was never divided. The amplification input stages are designed using ultra low-noise NOS transistors for the lowest noise floor. The circuitry uses audio-friendly C0G/NP0 ceramic capacitors and mechanical components.”
Basically, this means that the BB-P26 Mic Booster has high quality components, that supply very clean amplification to the signal. It won’t add any noise or coloration to the signal like some other mic boosters on the market, particularly any that feature a transformer-based amplification circuit. This results in up to 26dB of added gain between your microphone and preamp resulting in a clean, noise free, amplified signal.
If you’re new to soldering on circuit boards, this is a good kit to start with. The components are well spaced and the instructions are detailed and easy to follow. Artur has obviously taken time and effort to build a kit that is not just a great product, but one that can be put together by anyone with some basic soldering skills and a bit of patience. I put mine together in about an hour or so, without any problems. If you do run into any issues, Artur is easily contactable and always keen to give any advice. If you want more info on the mic build, check out my YouTube Channel video below.
Putting it to the Test
Once I built the BB-P26 Mic Booster, it was time to try it out. Instead of applying 48v to a signal path with my Ribbon mic and potentially destroying it, I decided to first test it with a Dynamic mic. I used an SM7b, another mic that could benefit from this mic booster kit. The signal was clean, and I was surprised how transparent the kit was even when engaging the boost switch. I then tried pairing it with the RM-5 Ribbon mic I had previously built from Bumblebee Pro, and we were in business.
The Ribbon mic now had that extra gain, without any noise, distortion or coloration and I tracked some acoustic guitars and drums that you can find in the YouTube video below. I tracked acoustic guitar with just the RM-5 Ribbon mic and for drums I used a Mid-Side pairing technique with the RM-5 Ribbon mic and a cardioid condenser microphone facing the kit, placed about 1.5 meters away. It came out great, so I might do a video tutorial on this soon.
End Thoughts
The BB-P26 Mic Booster from Bumblebee Pro offers a simple and affordable solution for using ribbon microphones in a variety of studio settings and if you’re not comfortable building one yourself, you can buy one pre-assembled from Artur and the Bumblebee Pro Team. If you have a small home studio without high end microphone preamps, you can now use a ribbon mic and get that extra signal that your interface preamps might lack. You can also use the Mic Booster on other dynamic mics that have notoriously low output, such as the SM7b. This on its own has me rethinking some possible uses for the classic dynamic mic.
If you’re fortunate enough to have some high-end preamps in your studio, the BB-P26 still offers the unintentional benefit as an in line, 48v Phantom Power protection circuit. I spoke to some colleagues I teach with about this and the idea of placing one of these in front of every ribbon we use, thereby protecting them from the trigger-happy students we work with, definitely piqued their interest. Even for myself, I now use the BB-P26 in my signal path as a default, just in case. Why not? A simple device, you can buy for a couple of hundred bucks to protect all those expensive ribbon mics sounds like a great idea to me.
You can Purchase the BB-P26 Mic Booster from here; http://www.bumblebeepro.com/shop/bb-p26-ribbon-mic-booster-diy-kit/
Comments