another mod question

[PhilGood]

How important is the output transformer to the sound of a mic? Is it pretty dramatic, or minorly perceptible? I mean, I know the ones in chinese mics are crap, but what about the difference between Jensen, Cinemag and AMI? Will I really hear a difference?

 

[PhilGood]

OK. I guess I chose a bad nickname. Was there another PhilGood who P.O.'d somebody? Am I being ignored or just no one knows the answer?

 

[crazydoc]

I don't think it's you. Just not many here with first hand knowledge of your question, especially regarding brand differences, myself included.

Transformers are generally felt to be a very significant part of the mic's quality and performance. Here's a thread that touches on it:
http://www.homerecording.com/bbs/showthread.php?t=124563

You can do a search for more.

Marik, a frequent poster here, has quite a bit of knowledge about this subject - maybe he'll add something.

 

[Marik]

How important is the output transformer to the sound of a mic? Is it pretty dramatic, or minorly perceptible? I mean, I know the ones in chinese mics are crap, but what about the difference between Jensen, Cinemag and AMI? Will I really hear a difference?

The transformer has a huge impact on overall sound. Since it is the last part in signal chain of the microphone before the signal hits a pre (let's disregards cable), it should have a wide band, and pass the signal without distortions and artifacts.
I am not familiar with AMI transformers, but Cinemags are very good. Since both Cinemag and Jensen have Nickel core their sonic signature is pretty similar, but Jensens are much more expensive. Also, you could check out Amorthous core Lundahl, which also is a very good iron, but sounds very different from Nickel.
It is really what kind of sound you are after.
One thing to point out. The simple transformer exchange would not make such a huge difference. The microphone is a system, in which everything should be balanced--quality of capsule, quality of parts used (esp. capacitors), quality of design, etc.

 

[PhilGood]

Marik, I highly value your input! I have done some of the mods you've listed and they have worked very well for me. Thanks!

I spoke with someone at AMI, which is in Gaylord Kansas.

http://www.tab-funkenwerk.com

They rewind and restore old Neumann Trafos or build replacements. I believe they are associated with Neumann USA, but I'm not THAT sure. The person I spoke to regarding their trafos went into a huge diatribe about the laminates and Cinemag vs. Jensen etc. He seemed to be a Senheiser/Nuemann evangelist. (who isn't)

The price for an AMI trafo for a chinese mic is $150. They have higher quality ones for $190. Jensen's are roughly $65. I spoke with Dave Geren at Cinemag who informed me that the Jensens are for DI boxes and Cinemag has trafos that are really designed for tube mics. Their cost for these is $40. Better laminates etc. than Jensen. Better in general? For less?

So is there going to be an audible difference for a Royer mod between the $150 AMI or should I just go with the $40 Cinemag? I also want to change the trafo in my Apex 460, but only if it's really going to make a difference.

Who do I trust? FOR THE LOVE OF GOD AND ALL THINGS GOOD, HELP ME!!

Aaahh! Glad I got that out...

 

[crazydoc]

...So is there going to be an audible difference for a Royer mod between the $150 AMI or should I just go with the $40 Cinemag? I also want to change the trafo in my Apex 460, but only if it's really going to make a difference.

...One thing to point out. The simple transformer exchange would not make such a huge difference. The microphone is a system, in which everything should be balanced--quality of capsule, quality of parts used (esp. capacitors), quality of design, etc.

I think this is your answer. Your quality is only as good as the weakest link. This goes for the signal chain inside the mic also - if you're passing the signal from a cheap Chinese capsule, possibly through poor quality caps, a top quality trafo isn't going to improve it, and might only make defects in the sound more apparent.

 

[PhilGood]

I think this is your answer. Your quality is only as good as the weakest link. This goes for the signal chain inside the mic also - if you're passing the signal from a cheap Chinese capsule, possibly through poor quality caps, a top quality trafo isn't going to improve it, and might only make defects in the sound more apparent.

Well, the cheap chinese caps are gone, since I've replaced it with the Royer Mod, so all that's left is the capsule and the trafo. I could use a peluso capsule if it's that much better.

 

[Flatpicker]

Some things I’ve learned from my friends Marik, Gus, and others:

In general, a Chinese mic can only be reasonably manufactured using a cheap low-ratio (2:1) output transformer. By reasonably I mean completely built in China using Chinese parts with no external parts vending or after-work involved. For this reason, they starve the tube plate current to create a tube output impedance that matches the cheap transformer to provide the correct 150 – 300 ohm output impedance.

The transformers you’ll get from Cinemag, Jensen, Lundahl, etc… are not only much greater quality, but have much higher ratios like 12:1 and are for REAL tube circuits – not the starved plate current designs. So the bottom line is, if you use one of these you’ll have to modify, if not completely rebuild the tube circuit as well.

(Marik, jump in here anytime and fill up the cracks I left. )

 

[Marik]

I spoke with someone at AMI, which is in Gaylord Kansas.

http://www.tab-funkenwerk.com

OK, now I see what we are talking about. The person you were talking to most likely was Oliver Archut himself. You don't expect him to tell you how good Cinemags are, don't you?

I spent two hours at Cinemag's facility in LA, talking to Tom and Dave. They know exactly what they are doing. Along with Lundahl, I use some of their stuff, and also, they do some custom work for me.
Check their website:

www.cinemag.biz

On the front page you will find a shootout between their new NiCo against U47 transformer. Listen to it and deside.

My pick on this.... If you've got some dough, first, get Neumann K87 or K67 capsule. It will sound good rolleyes with either Oliver's or Cinemag higher end transformers. Which one between them to choose? It is really a matter of taste.
If your budget limited, get 797 34mm capsule, and use Cinemag. I've got some mods for this capsule, and it can sound very good.

 

[PhilGood]

OK, now I see what we are talking about. The person you were talking to most likely was Oliver Archut himself. You don't expect him to tell you how good Cinemags are, don't you?

Ho-Nnooooo!!... as a matter of fact he was willing to send me a BV308 to try and said I could return in within 7 days if I didn't like it. The only condition was I couldn't cut the leads. I didn't ask him how good the Cinemag's were, he offered of his own valition. I asked Dave Geren how the Cinemags were. He was very concise. I like him. My question was: is the $150 AMI going to be THAT much better than the $40 Cinemag, or is that still just a matter of taste.

If your budget limited, get 797 34mm capsule, and use Cinemag. I've got some mods for this capsule, and it can sound very good.

Where would you get a bare 797 capsule without just buying an MXL 2003 and throwing the body away? (Then again, I could probably do the mod in the 2003 body and just get the trafo with the mu-metal can.) How you mod capsule?!! Me too clumsy to mess with 3 micron mylar and not get frustrated and throw capsule through wall!! Grrrr!!

How 'bout the capsules from John Peluso? Any good?

 

[Marik]

Some things I’ve learned from my friends Marik, Gus, and others:

In general, a Chinese mic can only be reasonably manufactured using a cheap low-ratio (2:1) output transformer. By reasonably I mean completely built in China using Chinese parts with no external parts vending or after-work involved. For this reason, they starve the tube plate current to create a tube output impedance that matches the cheap transformer to provide the correct 150 – 300 ohm output impedance.

The transformers you’ll get from Cinemag, Jensen, Lundahl, etc… are not only much greater quality, but have much higher ratios like 12:1 and are for REAL tube circuits – not the starved plate current designs. So the bottom line is, if you use one of these you’ll have to modify, if not completely rebuild the tube circuit as well.

(Marik, jump in here anytime and fill up the cracks I left. )

Well Tim.... OK I am jumping in
The 1:2 transformer is not that hard to manufacture and make more or less reasonable. The lower ratio--the easier make it. The problem is that Chinese transformers use very poor lamination, so they have high distortions, and inductance goes down and low end sucks as a result. If you do 1:2 the simple interleaving is already OK if you have enough turns.
Off-shelf 1:10 Chinese stuff still makes it 1 to 2 interleaving, which together with their lamination results in what we hear. I like Gus' joke about he thinks the Chinese lams are made out of car bumpers.
There are different ways of doing good quality high ratio transformers. One is to use E core and make a multisectional secondary, or make a multiple interleaving. Another way is to use L or U core (what Cinemag and Lundahl do). Of course, high quality lamination is essential, and the whole transformer should be calculated around it. Depending on your taste you can get high Nickel, Amorphous, or mixed Cobalt cores. All of them are good, but have different sonic signatures. You really have to listen to them to deside what you like.

BTW Tim, I think you are kinda refering to Nady 1050 mic. It does not use starving plate, but since they have only 1:2 and 1:10 off-shelf transformers, for some unexplainable reason they desided to use cathode follower in output. They put much lower current on output stage, and thus raise output impedance of the tube, so they could use 1:10 instead of 1:4. In fact, from top of my head I don't remember any mic, which uses starving plate.

 

[Flatpicker]

BTW Tim, I think you are kinda refering to Nady 1050 mic...

No, actually I was referring to the MXL V69. I'm not a very good tube mechanic ( ) but seems like it works simular to this...

 

[Marik]

Ho-Nnooooo!!... as a matter of fact he was willing to send me a BV308 to try and said I could return in within 7 days if I didn't like it. The only condition was I couldn't cut the leads. I didn't ask him how good the Cinemag's were, he offered of his own valition. I asked Dave Geren how the Cinemags were. He was very concise. I like him. My question was: is the $150 AMI going to be THAT much better than the $40 Cinemag, or is that still just a matter of taste.

Just get both to try and keep the one you like.

Where would you get a bare 797 capsule...

Call PMI and ask Brent nicely .

How 'bout the capsules from John Peluso? Any good?

Unfortunately, I did not have good experience dealing with him, and I don't like the way he conducts and promotes his business. Personally, I cannot recomend him.

 

[Flatpicker]

Oh, wait...

I'm thinking about the solid state mics using an extra transistor to match the cheap 2:1 transformer... Glad you "jumped" in, lol!

Nevermind...

 

[Marik]

No, actually I was referring to the MXL V69. I'm not a very good tube mechanic ( ) but seems like it works simular to this...

The V69 is transformerless.

 

[Marik]

Ha! look at the times. We miss each other by a few minutes. Lol

 

[Flatpicker]

The V69 is transformerless.

Hmmm... that's correct. Well maybe I was thinking about the Nady! You not only filled the cracks, you cemented a gaping hole!

I'll shut up now and go back to building solid state preamps which I'm a little more experienced with, hehe.

 

[PhilGood]

Holy Crap!! i just went to the PMI site and noticed that Alan Hyatt knows Tony Merrill from Stephen Paul Audio. I used to play drums for Tony back in 1990-91!!

I'VE GOT AN "IN"!!!!!!!!!!!!!!!

 

[chessrock]

Holy Crap!! i just went to the PMI site and noticed that Alan Hyatt knows Tony Merrill from Stephen Paul Audio. I used to play drums for Tony back in 1990-91!!

I'VE GOT AN "IN"!!!!!!!!!!!!!!!

Yea, and if you're really nice to him, he might let you buy one of his mics. Heck, he might even knock a buch off the shipping cost and autograph it for ya if he's in a good mood. You really kinda' have to be in his inner circle for that, though.

 

[PhilGood]

Yea, and if you're really nice to him, he might let you buy one of his mics. Heck, he might even knock a buch off the shipping cost and autograph it for ya if he's in a good mood. You really kinda' have to be in his inner circle for that, though.

Or I could just drive over there. That alone would save me $4.50...