Bumblebee Pro Audio

RM-5 Ribbon Microphone Kit

$250.00

Full Kit
Step-by-Step Guide
Supported
Beginner

Description
Audio
Docs

Artur Fischer's RM-5 is a classic, figure-8 ribbon microphone featuring modern, custom-designed components manufactured in Latvia. The RM-5 shares the warm and rounded tonal qualities associated with its vintage counterparts. However, at it's core the RM-5 is simply an exceptional transducer, capturing every source, from gritty electric guitars to hushed vocals, in a way that is natural, detailed, and balanced.

The RM-5 features the same stainless steel body and gold-plated XLR connector as the flagship RM-6 Ribbon Microphone.

To purchase the RM-5 outside of the US and Canada, please visit the DIY Audio Components Store.

Features:

RE-254 ribbon transducer made of 2.5µm Japanese aluminum foil and neodymium magnets
Custom RTP-35 transformer designed specifically to complement the RE-254 ribbon
Microphone body machined in Latvia of hand-selected stainless steel and matte polished for Bumblebee Pro's signature finish
Custom XLR recepticle with gold-plated pins for decades of reliability

DIY Friendly

The RM-5 kit is designed for beginners—you don't need any mic-building experience to successfully complete the build. The required tools are a soldering iron, some solder, and a hex wrench (Allen Key) set. The entire assembly includes only six solder joints. To ensure world-class performance, the kit comes with the RE-254 ribbon transducer pre-assembled and hand tuned. And finally, the kit is backed up by our friendly Guaranteed Support.

Kit Includes:

A shock mount is not included. The SM-28 is sold separately here.

RE-254 ribbon transducer (pre-assembled)
RTP-35 transformer
Stainless steel microphone body and mounting hardware
XLR insert with gold-plated pins

What is the difference between the RM-5 and RM-6 DIY Ribbon Mic kits?

The RM-5 and RM-6 are two different designs, they just share the same type of body. The main differences are:

RM-5 is a big ribbon mic with a 2″ ribbon; RM-6 is a small ribbon mic with a 1″ ribbon
As is typical for shorter ribbons; RM-6 has less distortion and sounds more "natural"
RM-6 has a slightly flatter frequency response than the RM-5
RM-6 has significantly higher output signal level, at least +3dB higher than RM-5
RM-6 has much lower magnetic flux leakage; there is practically no attraction between two microphones standing side by side
RM-6 motor comes with a 1.2u ribbon, while the RM-5 motor comes with a 2.5u ribbon
RM-6 comes with RTX-28 toroidal transformer optimized for thinner foil gauges

The samples below demonstrate the RM-5 on a range of sources. The acoustic guitar was mic'ed with RM-5s at the bridge and 12th fret. Electric guitars were double tracked; the "Soft Overdrive" was mic'ed with the RM-5 8" from the driver, on-axis while the "Hard Overdrive" was mic'ed with the RM-5 10" from the driver, slightly off-axis. The accordian was recorded with the RM-5's in a Blumlein pair configuration about 2' from the instrument. The brass quintet and church organ were recorded in The Netherlands by Jo Smeets in a Blumlein configuration. The harmonica was recorded with the RM-5 about 8" from the instrument.

Exactly What I Wanted in Another Ribbon Microphone

We think that the RM-5 kit represents the best known value for a dark, long ribbon, vintage design. Most modern ribbons have the warmth and smoothness that only ribbons offer, but are hyped in the top end using short ribbons, mechanical diffusers, or active circuitry. The RM-5 is not like that. It’s very old school and captures the dark, fat sound that you can only get from a long-ribbon design.

If you need to tame a strident vocal, a bright guitar cabinet, or a bleating horn, while keeping room reflections out of the mix, the RM-5 will shine. You can get by using a pair for stereo Blumlein recording, but you will miss some of the high-frequency detail and the room reflections that make this such a great recording technique. For Blumlein use, we recommend the RM-6, which is a modern ribbon design with better high-frequency response.

Either kit is great and they are easy to build. You get the enjoyment of building it yourself and saving potentially thousands over microphones which may not be any better.

Ribbon RM-5

Woah, what an epic little project! Worked the first time, was totally reasonable to get through the process, and sounds great!

Awesome Ribbon Mic and very simple build.

I built this mic a couple weeks ago and have used it almost daily. It was super simple to build (took me under 45 mins). I’ve tried it on acoustic and electric guitar, vocals and percussion and it definitely has a way more expensive sound than the cost of the kit!

Fun little project.

This was a very simple and fun DIY project. The housing is very solidly built. The end result is a little bit noisy (I'm running through a DIY:RE MB2), which is the only thing holding me back from giving it a full 5 stars, so maybe I'll play around with different transformers or even different ribbons/motors if I can find them.