Fethead to the rescue! (was "What to do with a crippled MD421?")

[Dubmaniac]

A few years ago, I got a used MD421 U-5. It sounded awful- weak output, pure midrange honk, zero bass. Very disappointing, and just about useless. Last year, I bought an EV V2 ribbon mic. It had extremely low output, as is to be expected from a vintage ribbon. I started looking for a Cloudlifter at a good price, but the used ones tend to go for almost as much as the new ones. I finally got a Fethead preamp and tried it with the EV ribbon. It's definitely louder, but it sounds like mush. Almost no high end, at least on vocals. I was thinking about sending back the Fethead, but I thought I'd try it first with a few dynamics. My Shure SM53 and My EV RE11 sounded fairly good, my AKG D200E, not so much. Then I looked up and saw my 421 sitting on a desk stand as a decoration on a speaker. I plugged it in, turned it up and WOW! It's rich, full, deep (good proximity effect), good highs and midrange- pretty much perfect! I sound like a million damn dollars just talking into it! My ribbon mic is kind of a letdown, but that's more than made up by getting to use my 421 after all this time, and the improvement in sound quality!

[trodden]

Interesting.
I wonder what specifically is going on with the 421 to make that the fix?

[Nick Sevilla]

Interesting.
I wonder what specifically is going on with the 421 to make that the fix?

MD421s have a "music / speech" switch, which is a black ring around the bottom of the mic, near the XLR connector.

If he had the switch on "speech", it would indeed sound thin and honky with a regular instrument.

https://assets.sennheiser.com/global-do ... 1_2022.pdf

[vvv]

I don't have the FEThead or Cloudlifter

I do have a pair of these and think they is the tease's knees:

https://www.cathedralpipes.site/the-dur ... p-208.html

[trodden]

Interesting.
I wonder what specifically is going on with the 421 to make that the fix?

MD421s have a "music / speech" switch, which is a black ring around the bottom of the mic, near the XLR connector.

If he had the switch on "speech", it would indeed sound thin and honky with a regular instrument.

https://assets.sennheiser.com/global-do ... 1_2022.pdf

Yeah, i know that. I always keep mine on M. Wonder why the Fet Head would change that though?

[Dubmaniac]

Interesting.
I wonder what specifically is going on with the 421 to make that the fix?

MD421s have a "music / speech" switch, which is a black ring around the bottom of the mic, near the XLR connector.

If he had the switch on "speech", it would indeed sound thin and honky with a regular instrument.

https://assets.sennheiser.com/global-do ... 1_2022.pdf

That was the first thing I checked. It made no difference. But now it makes quite a big difference. Fun fact- when plugged into the Fethead, even with the switch on "speech", it now has more bass than it ever did on its own. It sounds like what you would expect from a 421.

[winky dinglehoffer]

My 2 absolutely uninformed thoughts on what could possibly make a difference here:
1. Impedance. FETs have a very high impedance, & maybe that is helping to compensate for some issue upstream in the mic.
2. There's a bad connection within the mic (like pin 2 or pin 3 is not connected to the transformer, or there's a similar issue elsewhere in the mic), & the circuit of the FEThead is such that it works roughly the same whether that problem exists or not.

Whatever the cause, it's great you've found a way to make your mic useful.

[analogika]

Probably still a good idea to get that 421 fixed, though.

[The Scum]

Probably still a good idea to get that 421 fixed, though.

I agree. If the FETHead fixes it, then it seems like maybe there's a bad connection somewhere...the "low output and thin" symptom can be observed when one leg of the output transformer is floating.

Does anyone in North America have recent experience with Sennheiser service? I had some mixed experiences with them, but that was 20 years ago.

[trodden]

My 2 absolutely uninformed thoughts on what could possibly make a difference here:
1. Impedance. FETs have a very high impedance, & maybe that is helping to compensate for some issue upstream in the mic.
2. There's a bad connection within the mic (like pin 2 or pin 3 is not connected to the transformer, or there's a similar issue elsewhere in the mic), & the circuit of the FEThead is such that it works roughly the same whether that problem exists or not.

Whatever the cause, it's great you've found a way to make your mic useful.

Very good theories!

[Scodiddly]

Does anyone in North America have recent experience with Sennheiser service? I had some mixed experiences with them, but that was 20 years ago.

If it's an old one they won't have parts.

[digitaldrummer]

unless you can troubleshoot and fix it yourself (i.e., loose wire) your FEThead "fix" is probably a lot cheaper than if you send the mic back to Sennheiser and they essentially charge you for a new mic...

[KuruPrionz]

I don't have the FEThead or Cloudlifter

I do have a pair of these and think they is the tease's knees:

https://www.cathedralpipes.site/the-dur ... p-208.html

I have a Cloudlifter (pawn shop bargain) and a Cathedral Pipes. They don't sound much different at all, both are great little boxes.