Apex 460 Mod DIY Tutorial Video...

[Rossi]

On the transformer I measured (as I said, not the same mic), I measured a gain loss of about 21 dB and secondary inductance of 1.6H. primary inductance was off the meter (goes to 20H), but given a ratio of about 11:1 (could be 10.5:1 like the Cinemag, I don't care for the peanut crumbs), the primary inductance must be somewhere between 150-200H. Distortion was perfectly okay, too, and even at 47k source (+ 1.5k termination), the response looked good enough. Unfortunately my program ate some of the data. I'll post some curves later on.

 

[speakercoil]

So I did a final part of the mod which is optional today... I painted the body to get rid of the ugly black and the PPA logo... As I did not want to screw up the grill, I taped over it when spray painting everything... I used Rustoleum which is made for metal, and it has come out quite beautiful. I used their hammered series which gives a very detailed and pretty finish. At first I was going to spray paint the grill gold and then I thought... Hmmmm that would probably end up drying weird and clogging the holes in the mesh, completely ruining it. So I decided not to.

The finish came out amazing. I am waiting for it to dry right now. Then the mic is 100% finished... Minus a custom badge I want to have made for it... Anyone know a company that does curved metal badges that would stick on with adhesive of some sort?

-Grant

 

[3nity]

Since we are talking 460 mods here.
I have a CM-2510 transformer but i'm not sure it will work on the 460??
Thanls

 

[Rossi]

Here we go: Transformer in a t.bone SCT700mic whose circuit is similar to the Apex460 (it uses an 12AX7, though).
I measured with various source impedances. These measurements are not super accurate, I did not look at the actual source impedance of the sound card used (an Emu 1820m). I just hooked it up to the line out and used a Universal Audio DCS Preamp (DI in) for gain make up. The transformer secondary was terminated with a 1.5k resistor (typical mic pre input impedance). To simulate source impedance I used 10k, 22k and 47k resistors in series with the sound card line out.

Please note the fine dB scale, the response is flatter than it appears at first sight. Even at 47k the response is absolutely usable, especially since we'd like a little treble attenuation for the K67 style capsule anyway.

 

[Kingston]

Since we are talking 460 mods here.
I have a CM-2510 transformer but i'm not sure it will work on the 460??
Thanls

It'll work fine. You'll have a bit higher output impedance, but also a couple of dB more output. If it was only 5:1 ratio, it might not be such a good idea.

 

[speakercoil]

OK... So I am just dumped the video footage down and will begin editing the video tomorrow night. I filmed a lot of footage including a mistake a made early on (with the transformer wiring), and will have to go through it all and edit it down to an acceptable youtube tutorial amount of time.

The tonality of this mic is amazing now, and I am glad I went with the t14 instead of the cinemag... It's very smooth and creamy in the high end now. Lots of clarity. I tracked a lot of percussion with it this weekend... Let's just say I am working on a track with 14 different percussion parts and used this mic on all of them. I was expecting to have a big jumbled mess that I was going to have to EQ to make fit into place... Instead just a little bit of panning and everything fits perfectly... No harshness anywhere... I was blown away. I mean literally I don't think a single one of those tracks is going to need any EQ. I was so relieved.

I plan on making a second one of these soon, and will do a second round of video tutorial for it... Sort of a revisited shorter video to review the mods.

Also I want to mod a Nady TCM 1050 with a K47 and BV8 type of transformer if that is possible without significant circuit changes. Not sure if it is, and was kind of hoping someone could maybe shed some light on that.

I do want to do a G7 soon, but I am going to wait on Skylar's bodies to be done...

I will let you guys know when the video is up and posted! I have a pretty busy next two weeks, but will be fitting as much editing time in as possible.

-Grant

 

[Jim50hertz]

Hi grant,

I looked through the thread but couldn't find exactly which tranformer you used, you say T14 but not cinemag?

Any chance you can post a link?

Peace

Jim

 

[speakercoil]

Hey... Yeah ummm... Peluso claims you can get it from his site, but I couldn't find it on there. Just contact Peluso and he will get you one. He said he gets them custom made, but yet they have a Peluso badge on them so I have no idea who really makes them. All I know is that it sounds AMAZING. I guess it's supposed to be a clone of the original transformer used in the C12.

Hope that helps!

-Grant

 

[maxwall]

How about a listening test between the Stock 11:1 transformer , Peluso T14 and the Cinemag 2480 maybe there is not a big difference at all, just the peluso price tag for a custom knock off..

FYI , Advanced Audio offers parts too, prices are within reason.

http://www.aamicrophones.com/parts.htm

 

[speakercoil]

Nah, I don't think it's Peluso trying to hype things. I only say this because the cost of the two transformers from him are exactly the same. So it's not like he would be making any extra money. It is what he uses in his C12 clone mic. I will say having heard clips from other Apex mics, this one does sound less on the bright side... Which is what Peluso claimed. However this can always be attributed to a different signal chain, room, sound source, etc...

-Grant

 

[maxwall]

C12 is inherently a very bright sounding mic by nature so if the hi frequency in Peluso transformers are rolled off then they don't represent what I would expect, no big deal. more or less , it seems the lack of bright might be intended in the design maybe, if not then I would expect a repro to be able to attenuate highs like a real C12 , but this could also include the capsule influence as well which needs to be taken into perspective. I know there were at least three different
original C12 transformers , so its possible for it to be modeled from one that is not commonly heard of.

Nonetheless, your video ideas are now much anticipated and your mic build would add to the knowldge base around here.
Now quiet on the set , Grants Mic video .....take 2.

 

[speakercoil]

lol. Yeah I have begun editing it. I need to figure out what parts are crap and what parts are useful. There is a lot of me going "wait that looks out of focus, let me zoom", when in reality it was in focus all along and it was the crappy LCD on the camera that sucked. So there is a lot of useless areas to get rid of. Also I ramble at times so I might do a voice over at parts explaining what is going on (which would be done with the mic!)

I will warn everyone, I was kind of brutal in my approach to modifying this mic. What I mean is that a lot of it wasn't done very safely... As in... No safety goggles, no safety mask, sometimes soldering in my lap to try and get a better camera angle. However the actual footage turned out great. There are times when my arm blocks the camera, but the critical parts seem to be in place. It's a lot of the repetitive work that got blocked. Oh, and excuse any foul language I use when trying to screw in the capsule... That part was ridiculously annoying. Possibly the smallest screws on the planet and they kept falling... Hence the swearing. lol...

I know, I was expecting the mic to be much brighter considering the nature of the C12. I have used the C12 reissue many times, and been sitting in on sessions where vintage ones were used. I had no idea there were three different transformers made for it over time?!?!?!? That's crazy, but awesome.

This is what Peluso told me when I was inquiring... I hope he doesn't mind me quoting and e-mail...

"Hi Grant:
Yes I do have a CM2480 75.00 each with 34.78 next day air. We also have our Custom Made T/14/1 AKG C-12 transformer remake same price but not as brutally bright as the 2480."

Oh yeah I got it overnighted because I wanted to do the mod for a session that weekend and had all parts arriving that friday except Cinemag hadn't contacted me yet! Actually it took cinemag about 2-3 weeks to finally get to me. They said they are very busy with orders, especially for that transformer... Wonder why? lol. Actually I guess they said a lot of OEM guys are ordering it in bulk besides just us 1-2 piece order guys.

-Grant

 

[shot]

What happened with the video?!? Did you edit it? Can you post it?

 

[olympiaboy23]

Hey guys im new modding i recently did  the advanced audio mod  for the apex 460. Everything seemed great till i plugged it up and noticed its recording really low to where i have to turn The gain all the way up om my Preamp can you please tell me what i need to do to fix this. With preamp gain all the way up im gettin lots of noise

 

[RuudNL]

Where is the video? (We live 3,5 years later now...)

 

[okgb]

FWIW , I tried phoning & emailing  peluso a few times asking about their
" Shoeps " references with their sd mics and never received a response ,
I moved on and bought the real thing .
my 460 mod with Cinemag  [ a great company by my experience ] sounds quite
improved over the stock unit, I replaced the tube with 12ay7 and changed the one output cap to
to a non polar mylar type , that's all .