Sennheiser MKH20 Ring responses

All about the tools and techniques involved in capturing sound, in the studio or on location.

Moderator: Moderators

Post Reply

Sennheiser MKH20 Ring responses

Post by Hugh Robjohns »

Sennheiser's MKH20 omnidirectional microphone is supplied with a flat rubber ring to acoustically alter the mic's frequency and polar response in a broadly similar way to the use of 'Acoustic Spheres' available for other brands of omnidirectional microphone.

However, the published chart detailing the way it changes the frequency response is often lost and hard to find on the Internet — and very difficult to read even when found — so I've carefully re-drawn it here for the benefit of future enquirers.

The ring has an outer diameter of 35mm, an inner diameter of 25mm, and is 6mm thick. It must be fitted such that it is flush with the top of the microphone housing.

The information Sennheiser provides with the ring states "This pressure build-up ring increases sensitivity of the MKH20 within the frequency range 4 to 10kHz by approximately 2dB. In conjunction with the diffuse field equalisation the ring enables an easy matching of the frequency response to a given recording situation."
MKH20 Ring responses.jpg
In essence, the ring provides a modest 2dB boost between 4-10kHz, centred on 8kHz. When used with the microphone in its flat response it also provides a gentle roll-off above 15kHz. The ring can be used in combination with the microphone's diffuse-field correction EQ, if desired (the diffuse-field switch introduces a high-shelf boost reaching +6dB at 10kHz).

The microphone's polar response is naturally more directional at high frequencies, with the front/back ratio falling above 1kHz to roughly 5dB at 6kHz, and reaching 15dB at 16kHz. Fitting the ring is likely to increase this ratio further above 4kHz but, sadly, Sennheiser has not (AFAIK) published polar-pattern plots detailing the resulting changes.
User avatar
Hugh Robjohns
Moderator
Posts: 32374 Joined: Fri Jul 25, 2003 12:00 am Location: Worcestershire, UK
Technical Editor, Sound On Sound...
(But generally posting my own personal views and not necessarily those of SOS, the company or the magazine!)
In my world, things get less strange when I read the manual... 

Re: Sennheiser MKH20 Ring responses

Post by forumuser840717 »

I always find that the biggest sonic improvement comes when one drives through the 4" nail to hold the ring in place :tongue:
forumuser840717
Regular
Posts: 347 Joined: Thu Jun 16, 2016 5:20 pm

Re: Sennheiser MKH20 Ring responses

Post by Hugh Robjohns »

:lol:
User avatar
Hugh Robjohns
Moderator
Posts: 32374 Joined: Fri Jul 25, 2003 12:00 am Location: Worcestershire, UK
Technical Editor, Sound On Sound...
(But generally posting my own personal views and not necessarily those of SOS, the company or the magazine!)
In my world, things get less strange when I read the manual... 

Re: Sennheiser MKH20 Ring responses

Post by MOF »

I always find that the biggest sonic improvement comes when one drives through the 4" nail to hold the ring in place :tongue:

Do you have any advice as to what sort of hammer one should use? Just asking for a friend. :lol:
MOF
Frequent Poster
Posts: 1758 Joined: Thu Mar 06, 2003 12:00 am Location: United Kingdom

Re: Sennheiser MKH20 Ring responses

Post by jimjazzdad »

All joking aside, the MKH20 is a fantastic mic; its a pity that Sennheiser has stopped making it. I have not done a head-to-head comparison with the MKH8020 (I don't have access to a pair of the newer ones) but I have read that they are "not quite the same". Any opinion Mr. Robjohns? A pair of closely spaced MKH20 is my all-time favourite setup for grand piano. Your post has reminded me I must try the rings when using them as main pair / room mics.
User avatar
jimjazzdad
Regular
Posts: 127 Joined: Sun Dec 15, 2013 12:00 am
Halifax, NS, CANADA

Re: Sennheiser MKH20 Ring responses

Post by Hugh Robjohns »

A friend has some 8020s which are excellent, but when I compared them I ended up preferring the MKH20s -- although I'm struggling to come up with a rational reason for that preference.

I'm a fan of the MKH mics in general and have rather a lot of them, although one of my (five) MKH20s has started whistling at around 16kHz so it needs a visit to the lab to be realigned.
User avatar
Hugh Robjohns
Moderator
Posts: 32374 Joined: Fri Jul 25, 2003 12:00 am Location: Worcestershire, UK
Technical Editor, Sound On Sound...
(But generally posting my own personal views and not necessarily those of SOS, the company or the magazine!)
In my world, things get less strange when I read the manual... 

Re: Sennheiser MKH20 Ring responses

Post by John Willett »

I could have sworn I have seen a polar plot of the MKH 20 with ring, but I cannot be sure - I will have a look.

In many ways I still prefer the MKH 20/30/40 series to the 8000 series - but I do have pairs of both MKH 40/8040 and MKH 20/8020 in both versions.

Though I now do tend to use my Gefell M221 omnis on piano more (nickel diaphragm capsule) ;)
User avatar
John Willett
Jedi Poster
Posts: 7250 Joined: Tue Mar 07, 2000 12:00 am Location: Oxfordshire UK
John
Sound-Link ProAudio
Circle Sound Services
Sound-Link are UK Distributors for: Microtech Gefell, ME-Geithain, AETA, HUM, Håkan, Meyer Turtle

Re: Sennheiser MKH20 Ring responses

Post by Arpangel »

Hugh Robjohns wrote: Tue Sep 21, 2021 10:50 am A friend has some 8020s which are excellent, but when I compared them I ended up preferring the MKH20s -- although I'm struggling to come up with a rational reason for that preference.

I prefer the MKH20 too, I think the 8020 "may" sound brighter overall, all I’m doing is asking if you can confirm this, or not, just wondering what differences people are hearing?
User avatar
Arpangel
Jedi Poster
Posts: 9194 Joined: Sat Jul 12, 2003 12:00 am
"Don’t let the noise of other peoples opinions drown your inner voice"
Post Reply