The AM Forum

I am partial to the WECo 639, and the Turner 99 :D

http://radiomagonline.com/media/2007/0607/706rad1502lg.jpg

http://www.k-bay106.com/turn_999.jpg

I suspect about half of you will say the D-104.  Nothing wrong with that! 8)

So what say? :)

73DG

ALL of me says the D-104.

I will say the D-104 as well.  But I have been looking for years for a nice old studio RCA ribbon or at least a Electro Voice ribbon to add to my shack.

RE20 or 27

Years ago, when I was in the sound and recording business, I had a pair of Shure 330 ribbons. Great sounding mics. Don't know what they're going for now, but they might be another ribbon to add to your list.

Behringer B1 - No doubt about it!  I have an RE-20 - it is very good, but the B1 is smoother, and definitely has better frequency response.

Vintage rig high Z any 10 meg xtal mic

Modern low Z gear most any dynamic can be made to sound good with processing (most low Z modern mics require processing).

Avoid:  Condensers, hand held mics (except in the car), ribbon mics.

Blain

I like my RE15.  It's the daddy of the rest of the RE series.  OK OK There is the RE 10, 11 But this is still my  fav..  It's what you hear from my station

http://www.coutant.org/contents.html#ev

Al

I like the Heil PR-40. It's even made in 'merica. 

However, just about anything old looks better than just about anything new.

well, define 'ham' microphone.. whether specifically marketed to hams, or, meaning that hams use them.. In any case, for m the old desktop mike from an RCA or GE base station, I think it is an EV. Has a bar with a locking key as well.

Steve, I agree, the large diaphragm condenser mics sound awesome, I have a 20 year old AKG C3000 that blows away any of my RE20/27's and my sure SM7B
what I don't like about the condensers is the very large pickup pattern, the B1 and the Marshall MX990 hears everything in the room, too much noise for me.
the sharp cardioid pattern on the RE20's gives good if not great off axis rejection.
nothing worse than hearing blowers and fans or transformers humming on air.
now if I am recording someone singing, I use the condenser, but for on air, especially in a multi microphone setup, I'll take the re20 any day.

D-104, EV 664, EV 636, EV 623, and Shure 55 in that order.  (Buzzard Microphones)  ;D

73,  Jack, W9GT

For almost 30 years I've tried all kinds of mics. They were always cheap, "ham" mikes from flea markets. Eventually I settled on a $3 Radio Shark electret cartridge. It worked "OK" but had its problems.

Finally, about 10 years ago I found the mic that made all the difference... the ElectroVoice RE-20.    Mike/ W2ZE gave me a super deal on it with a boom. After EQing and some processing this mic put me into the hi-fi class with the E-rig and 4X1. Before this it was marginal. What a mic !!

As mentioned here, room noise is a BIG issue. I can rotate the RE-20 until I null out a lot of the blower noise from the various amps or AM rigs here. It's not always 180 degrees, but something less for the null.   This gives another -15db+ of noise reduction, especially on SSB where blower noise can get out of hand when running some RF speech processing for DX work.

I use the RE-20 for ALL modes of ham operation - and recording. A used one can be had for $250?  If a directional mike is not needed, then a Berhinger B1 for <$100 is a steal. (if you're lucky to get one that holds together for a few years)

The bottom line is it pays to find a good quality mike. It all starts there. For years I fooled myself into thinking I could cheap out there.  A hi-fi mike with good directional characteristics is a plus.  An RE-20 will hold its value too, just like a Collins radio.  The RE-20 and its later version, the RE-27, have been used for decades in many TV, radio and recording studios throughout the whirl.



T

I have had nothing but problems with my B-1. I'm thinking of going with an inexpensive ribbon mic since I never used one.

 

Someone mentioned an AKG C-3000.  I use an AKG C-4000B condenser almost exclusively.  Have compared it to an MXl 990, Shure SM-7B, Shure 330 ribbon, Nady RSM-4 ribbon, several other Chinese 'cheapo' condensers (which have gone to hamfest heaven), even a RCA 77D.  I keep returning to the C-4000B set to the hypercardoid mode.  Well, anyway, for what its worth...a lot of this is 'what ever sounds good to you'.

I've used many mikes in the past; D104, 10DA, Shure, Electrovoice, etc
but always come back to my 1950's American DR332 from Pasadena, CA.

Never heard of it?  Google it at "American DR332 Mike", there's an interesting
complete writeup on the DR mikes along with an audio clip. I also have a 50
ohm D8 that I use occasionally.  The specs for it are also included in the '332
writeup...

Does the job and I'm told and with the correct EQ, reproduces my vocal output
closely ...  

Too many guys try to sound like something their not by EQing that extra (muddy)
bass into their audio  ...   Either you have it naturally or you don't; live with it!

The unamplified D-104 is right at the top, if the crystal is working into the proper load, ≥ 5 megohms, preferably closer to 10 megs.

Mine works into 20 megohms, but it takes special circuitry to successfully do that.

Also, the D-104 mixed in with a dynamic that has good low frequency response.

I agree with Don, going by the 'ham' description. Works with pretty much anything, requires no outboard processing or equalizing to sound pretty damned good right out of the box. For quality, utility, and longevity, nothing comes close.

Been having fun with the RCA 77D for the last few months, love it and it gets excellent reports. Has switchable patterns as well as impedance. But it's a commercial broadcast/recording mic, and requires some "adjustments" for ham use. Plug it in straight, it sounds soft and mushy.

Don's 2 mic setup sounds great with his strapping carrier. Clean and smooth, easy on the ears.

My favorite is a Heil boom setup with dual elements, a HC4 and 5. The 5 gets nice AM reports with the TS-950SD audio and IF BW opened as wide as it can go

My AM only rigs mikes are all unamplified D-104's. I dont like a bunch of different ones obviously.

Carl

RadioShack® PC-Mount Condenser Microphone Element
Model:  270-090
Catalog #: 270-090

$3.19

It's the only thing I use in all my microphones, using a little pre-emphasis circuit that Steve QIX shared with me back in the early '80s. It broke my heart to see the price go up from $2.79 which effectively moved it into the high priced class of microphones.

Rob W1AEX

On the Drake I like the Marshall 990. On the Viking Bud it's an old Shure Prolog hi Z!

Love the Marshall 990 into the Behringer when using the DX-60 or the TS-570.

For the Viking II, my unamplified, plain stand (no PTT's on handle or base) two-wire D-104 is the hot ticket.

D-104 w/o the preamp in the base. Some are better than others as they do vary somewhat. They have a crisp articulation, which to my ears, is superior to dynamics. This, of course, is for vacuum tube transmitters requiring hi Z mics. Too bad they are not being made anymore, but they are still easily had at hamfests for about $30. Most of the half dozen or so I have came with the preamp in the base. I just bypass the preamp.

EV 664 is my favorite:

(http://k9toa.net/sitebuildercontent/sitebuilderpictures/664x4.jpg)

Back in the early days, my favorite was a Lafayette PA-42:

(http://www.retromicrophones.com/images/mic/lafayette_crystal_6900.gif)

I like the full bodied, classic sound.


klc

There's not a lot of difference among the RE-10, 11, 15 and 16.   All of them roll off around 80 cps on the low end, and somewhere around 11K at the top end. They all have a cardioid pattern with a null you can aim toward ambient noise and attenuate it somewhat.

The 635A for about $90 is one of the best "voice" response microphones out there, as is the RE-50, which is a 635A in another housing that minimizes handling noise and wind noise. No need for a windscreen. Omnidirectional, so you can get off-axis without changing the sound, while giving up the null that can cut a noise source in the room.

Right now I'm seeing the famous Shure SM57 and SM58 going for the same money -- that's a deal.  I think they're both omnidirectional. You get broadcast quality construction / ruggedness, strong quality control, and an audio response curve good for vocals.  Rolls off around 95cps, top end is about 10K.

http://www.bswusa.com/proditem.asp?item=SM58LC

The SM57 is cardiod.  The SM58 and 57 are ubiquitous stage microphones.  Someone told me they are no longer made in America.  That is just a rumor. I bet someone on this forum actually knows.

http://www.shure.com/americas/products/microphones/sm/sm57-instrument-microphone

I'm trying to buy another 664 (that would make 3 of them) but I still like my old D-104's.

A pair of NIB 664's with matching stands just sold for $220.00.  Too rich for my blood.

D104...all though it has a new high Z X-tal cartridge and JFET preamp.. (is it still a D104?)
and I like my Behringer C-1

The only AMers with a good sounding D10-4s are Dirk (CYT) and Tim (HLR).  I'm sure there are others but on my HIFI receiving system, they're the best.  Most others have verying degrees of level of fingenail-scratching-on-blackboard to ear-bleeding audio.  Most of the time the copy is good though.

That's either on my SP600 + SE3 SAM or the Flex.   RX AF chain = Dynaco PAT5 + Stereo 80 + AR bookshelves - the sound is the same - good if the source is good.

Al

I see your bad sounding D-104s and raise you bad audio from fancy audio chains with the knobs turned to 11. Maybe this only happens on the left coast.

Very, very nice receive set-up by the way.

FWIW..... I just purchased an SM58 several months ago.  I haven't checked where they are made (I think their headquarters is in Chicago), but I have used many of them over the years.   If your rig has a Lo-Z mic input, the SM58 should work very well.  It has a slight rising frequency response that tends to sound pretty good on most transceivers.

I presently have an SM58 connected to my K3, no other processing, and have tweaked the K3's hi end EQ a bit, as well as setting the compression level to about 6-8db on peaks.  I got "broadcast quality" comments from several stations on 40.   YMMV.

73
Ted  W8IXY

Very well put.  We are really plagued locally by an ESSBer on 3860 (or there abouts) who,
 
1) puts on tons of reverb 
2) tons of compression,
3) a wide BW setting, 
4) tons of overdrive to linear.

Result is a very broad signal both on lower SB and really crappy upper SB components er distortion products and a constant din of plain crap downband and upband.

Al

My favorite ham microphone is Irb's D-104 with 60 years of brown crud on the front screen:

EUUWWW!

If it has the original Astatic high Z crystal or ceramic cartridge, and no amplifier in the base, it's a Dee One Oh Four.

If it has an amplifier in the base, or some other type of cartridge JSed into the head, that makes it a Dee Ten Four.   ;D

Wow the S20R.  I have one of those.  I should get to work on it.

I also have a genuwine Dee 1 oh 4--G stand, Astatic high Z ceramic element, Amphenol connector.  It was part of an estate and regarded as the worst mic there.   I have quickly learned the D104s most folks don't want are the good ones.

This is what a real D-1O4 looks like.

And  here's another one.

Is that yours in the first set of pics, Don? If so, looks like you were able to snag one of those bakelite cord grommets as well as getting it mounted in a ring. Nice rope job! Need to find a ring holder for mine someday.

I'd always seen the D-104 ceramic elements as best suited for SSB work. Never heard one that sounded as nice as a good working crystal element. Does yours have a green tag on top Rob, or a -C after the designation?

Yes, the ones in the first set are mine.  The one in the desk stand still has the original grommet (hard rubber, I think). The one on the boom stand was one I reconstructed.  The threaded barrel part had disintegrated, but the visible part was still sound. I carefully filed away the remains of the barrel, and epoxied it to a piece of threaded brass that I had carefully cut and filed to fit. So far, it seems to be holding together fine.

I still have the ceramic element, but haven't used it for years.  They don't have the output that the real crystals do.  I got it because I thought the high humidity we have here would quickly destroy a crystal one, but after decades, none of my crystal ones has ever gone bad, although several mics that I have picked up at hamfests were duds.

The one on the boom stand is the one I got off ePay after the listing was posted in this board.  Turns out it had been partially  re-assembled with post-1937 parts, but I had another incomplete head, and between the two I was able to assemble one with all the correct period parts. The threads in one of the holes for the eyelets had been stripped, but I fixed that with JB Weld. It's amazing how Hammy Hambone can manage to screw some things so completely up.

I copied the  rope configuration from the Dutch photo in the second posting. The ring I'm using is actually too small for the mic, so not enough room inside for spring mount, but the rope suspension works fine. The smaller ring is perfect for the boom stand, which I fabricated out of an old workbench lamp that probably dates back before WW2.  Came from an old-timer's work bench in a pile of junk I got.  I quit using the lamp years ago because I got tired of banging my head on the damned thing.

I like the T-17 microphone used in conjunction with a high level splatter choke. Now that's a sound to strive for!

Hi Todd, well the deal with the ceramics is they are less risky--most of the crystal salt elements out there have probably been destroyed.  There was a brief item in ER around a year ago on how to "restore" a D104 by a ham in AZ who began by saying he put his mic in his garage and left it there for a few years (in AZ in summer, the garage temp. probably hit 200 F).  So his restoration involved  sticking one of those Kobitone elements in it.   With hams like that you can see how these mics get wrecked.  Anyway, I have no idea now if mine has a green tag on top or C in the cartridge part number--I just don't remember.  I know it is a ceramic because it either says so on it, or at the time when I looked at it, I put the part number into google and found out it is ceramic.  What does the green tag mean?

I once had a crystal microphone on a homebrew AM transmitter I built years ago made by Olson Radio. I could not find a picture of it in a Google Images search, but let me describe it. It was sort of a dark forest green with a chrome grill on a short desk stand. The mic part could be tilted up and down. Anybody know what that might have been?


I fully agree. I've tried a lot of mics over the years, but the D-104 is the best for weak signal work. I wrote an article that talks about the D-104 and SSB at http://www.w0btu.com/ssb_audio-weak_signal.html.

However, when I ever get around to building my 833 AM transmitter, I certainly won't use the 100K load resistor that I describe in that article. :-)

I took the back off mine and found the mic element is black (plastic I guess) and a small rectangular label pasted on the back which may have been light green said:   
Made with
"CERAMIC"
Heat and Moisture
Resistant Element
Astatic Corp.
Conneaut Ohio

and stamped on the label with purple ink was:  637

I've attached a photo of the D-104 ceramic here, Rob. Dug it out a few months back when we had a lengthy discussion about the different types. It's clearly an older example as the tag is riveted to the top. Green paint along with the word 'ceramic' embossed. I've seen one other that had a -C stamped after the D-104 nomenclature on the top tag.

My guess is that they discarded the green tag approach for cost reasons and went with the stamped foil tags, or maybe just added an inside tag, though this wouldn't give the user any idea of the element inside. This assumes that the generic D-104 was assumed to be crystal unless otherwise noted. When folks changed out a cartridge at home, any company naming convention would be a moot point.


There's a passel of D-104s here, many have come with other rigs. One came with the big AM rig which also included a CE 200V in the deal. The same mic is wired for and works with both rigs. Another came with a Drake TR-6 that a friend used exclusively for SSB work. Another came with a set of RELiant/Eldico twins, also SSB. So there would appear to be no exclusivity for the crystal versions being made for AM. They just mate up and work well with most of the old rigs. Clearly folks recognized the abilities of the mic regardless of mode. They are punchy.

The original crystal element remains in the D-104 that came with the big rig back in '88 and still works great, despite being knocked over several times by me and dropped on the floor once, as well as experiencing numerous temperature swings. Who knows what it went through prior to my getting it, but it was already old then.

 

Back in the 60s, just before the major AM vs Slopbucket Wars exploded, urban legend had it that the D-104 was "no good" for SSB.

I think the problem was that most of the SSB rigs then were using such narrow and pinched audio, that combined with the acoustical peak in the D-104, it sounded too tinny even for those obsessed with "communications quality" audio.  For a D-104 to sound good, it needs good low-end response to complement the upper mid-range peak. That's why Astatic always recommended a minimum of 5 megohms grid resistance for the mic to work into.

RCA recommends a maximum of about 0.5 megohms grid resistance for most tubes, but I have never had a problem with up to 5 megs.  10 megs can be made to work, but the tube must be carefully selected to avoid bias and plate current drift, particularly in a push-pull  circuit where the tubes must be balanced. 

I load my D-104 with 20 megohms, by using the push-pull preamp, with 10 megs grid resistor at each tube.  I had to  carefully select tubes for balance and absence of hum.

I have a circuit somewhere for a special cathode follower circuit designed especially for crystal mics.  It maintains a low grid resistance for the tube, but by inverse feedback makes the effective load resistance to the mic almost infinite. If I can locate it, I'll try to scan or copy it and post it here.  I have never tried it, but it might be an interesting project.

For years I used the D-104 working into a 12AX7, combined with a dynamic mic I have with a particularly poor high frequency response.  Since I built the push-pull preamp I have been using the D-104 standing alone.  I have several good crystal elements, and one of my "round toits" is to evaluate all my elements and use the one that produces the best sound with the push-pull pre-amp.  I have noticed a significant variation in the low-frequency response amongst the elements I have on hand.

In addition to the built-in presence rise in the D-104, I add about 8-9 dB of additional boost in the pre-amp. But I try to maintain good low frequency response all way down below 100~. Something peculiar I have noticed, especially with one of my mics, is that the D-104 actually has superior response to the dynamic at near sub-audible frequencies. Sometimes I get 30-50% modulation with what looks like a sub-sonic sine wave.  For a long time I thought it was a malfunction in the pre-amp, but finally discovered it was the sound of distant aircraft, that I could just barely hear. I could switch between the dynamic and D-104, and the low frequency rumble would go away with the dynamic standing alone.  Yet the dynamic added to the audible lows within the voice range.

The combination always sounded good with my voice, but I have had guest operators whose voice sounded terrible with the same mic settings.  This suggests that the mic and preamp response curves should be set to custom match the operator's voice.

My first AM microphone was an Electrovoice 638 and of course I used a T17 on the military gear.

Steve W1QIX (KA1SI at that time), did not like this sound at all. The Electrovoice was replaced by a microphone described to me over the air by Steve. It was simply a Radio shack electret mounted with contact cement behind a 1/8" countersunk hole on a 6 inch square piece of plexiglass set at a 45 degree angle into a chunk of walnut with big rubber feet on it. It had an onboard FET follower. This contraption was Hi-Fi compared to the the Dynamic.

Nowadays I want mobility so use a surplus Dynamic "entertainment" hand mic with decent specs and a long cord and walk around the shack.

Mike WU2D

Years ago I had a D104 that had much more low end then any of the other D104s in my collection.  I removed the grille and found this element had a single pin hole in the metal face of the cartridge. This hole was not in the center but half way from the center to the edge.

This prompted me to check my other D104 cartridges and I found the hole on some mics.  If one hole adds bass, a second will add more right? 

I believe this was a factory modification. On some cartridges the hole is punched and NOT poked with a pin. You can see a nice clean edge. The good news is that I took a single safety pin and punched a hole in a D104 and sure enough, I got that added low end.  The theory is that the pressure is less behind the metal cone allowing it to move easier on low end frequencys. 

The bad news is, I hate to modify any D104 cartridge as they are sacred to me and I do not suggest you go sticking pins through your Cartrdge. 

C

Maybe that explains why CBers sometimes poke multiple holes in the D-104 diaphragm and make it look like a salt shaker.

I once bought a cartridge brand new back in the early 60s, and when it arrived, it had the fibreglass disc over the diaphragm.  I thought that was packing material and discarded it.  Then I noticed the hole in the diaphragm, and figured it got punched  by accident, so I took a drop of glue and sealed it.

Eventually, I figured out that the hole and fibreglass disc were supposed to be there.  I took some fibreglass insulation and recreated another disc, and re-punched the hole.  Don't recall if it made any difference in the sound.

Been listening to you lately Blaine, you've got your audio dialed in nicely. SO which are you running, the 20 or the 27?
I had an RE-20 in the 1980s on my homebrew transmitter.  It did okay.  A broadcast supply house came up with an introductory offer for what was the new RE-27, a big discount if you traded in a working RE-20. 

I saw the specs, and heard some good analysis of the differences, and went for it. 

Sure enough, on my voice the '27 sounds better. There's also the advantage (to anyone) of a higher output from the 27's voice coil compared to the '20, so your mic pre-amp does not have to work as hard, conceivably meaning a lower noise level.

Pause for this message:

From the ZRF Estate Sale, there is an Electro-Voice RE-27, with original mic holder PLUS the (optional) matching suspension cage, and a pop-filter.

Package deal. Those interested, please consider, and send a note to Dave, W2VW with offers. Proceeds entirely to the family.

It's clean, never been smoked on, and if you heard and remember Dave's voice with that low end, this is the mic that started his audio chain.

EV has a new RE mic the 320 I think it is, priced to compete with the PR40.  I wonder if they brought it out to try to hang on to customers Bob was stealing away with the PR40.  I've heard more broadcasters talking about the PR40 and liking it. 

Paul,
I am currently using the RE27, I also have a few RE20's and find that they are very similar in sound, and I can hear the presence rise on the 27.
i run them all through separate symetrix 528e's and 528's and really the only difference is the gain setting on the mic preamp and a little more high end boost on the parametric for the 20's, then everything gets mixed down and sent through the Breakaway Broadcast processor then into the E-rig.
I have been looking at the re320, its not a bad price and looks cool with the black finish

I kinda like the microphone Charles Herrold used in his ARC PHONE transmitter.........

http://www.charlesherrold.org/know.html

The microphone was in series with the B+ and modulated the "carrier". A battle still goes on for him, that he was the very first scheduled broadcaster on the air. Even though using the spark technology. He lost out when radio stations went on the air with TUBES and generate frequencies instead of a tuned hash.
In the link there is offered a very informative background and ( I have) the VHS tape about this guy and his love of radio. It's about 1 hour long. Kinda like a PBS presentation.
CLIK on this link  and you will see some pictures and narration of his station
http://www.charlesherrold.org/see.html

Can you imagine the excitement over radio back then????

Electro Voice RE320.

Good looking set-up.
Is that a Gates/Harris board of some kind?
The switches look like those on the older sister to the Stereo 80, but the meters look more like an LPB.

I have not heard nor messed with the RE-320, so I looked it up just now.

Interesting response curve and comparison to the ones I do know.  Should be a good vocal mic for what we do on AM.
Looking forward to hearing you on it.

The board is a LPB Signature 3 model S-24 , 12 channel with 3 inputs per channel, built in 89. Picked it up from a local TV station which had some older gear in a rented climate storage unit and wanted to clean it out to stop the rent. I passed on (3) 7 ft RCA racks , what a dummy !