AML ezAM16-500

Just saw this  a new micpre there. Anyone knows what kind of pre it is? 1073 without EQ? :http://www.audiomaintenance.com/acatalog/aml-17-030_extended_info.html

Langevin AM16 maybe?

oh, thanks.  Does it sound more like an API micpre?

I have no idea  ;D I'm just guessing. Might be a different design.
I'm pretty sure Colin will let us know sooner or later.

Looks like Langevin.  Langevin is push pull from in to out.  Been on my list for a while, very simple circuit but the trafos are very important, and I hear difficult to wind.  Originals were probably wound by Reichenbach, since Cinemag still offers remakes, I wonder if this PCB will take those? 

Anyway, here is the schematic from Cinemag's site.:

http://cinemag.biz/application_notes/PDF/AN-107.pdf

I'd like to know how he's changing gain, I thought these were fixed gain amps?

mitsos said:

Anyway, here is the schematic from Cinemag's site.:

http://cinemag.biz/application_notes/PDF/AN-107.pdf

I'd like to know how he's changing gain, I thought these were fixed gain amps?

Click to expand...

In the schematic there's a 1K linear pot on the secondaries. Wouldn't this affect the gain?

BTW, what are these 4 white "bricks" on the PCB? 

warpie said:

mitsos said:

Anyway, here is the schematic from Cinemag's site.:

http://cinemag.biz/application_notes/PDF/AN-107.pdf

I'd like to know how he's changing gain, I thought these were fixed gain amps?

Click to expand...

In the schematic there's a 1K linear pot on the secondaries. Wouldn't this affect the gain?

BTW, what are these 4 white "bricks" on the PCB? 

Click to expand...

Power resistors according to the build guide

The instructions pdf is available, it shows that it's a Langevin AM16. now I'm curious how it sounds.
http://www.audiomaintenance.com/downloads/ezam16-500_colourbook.pdf

We compared it to an API console, it sounds similar, some sources were better through the console, some sources were better through these (just as you would expect).

The idea of this kit was to make something which is easy enough for beginners to make but good quality and also cheap like API kits.

Colin
www.audiomaintenance.com

Would it be possible to add an output attenuator to the ezAM16-500, so that you can drive the input transformer to saturation?

Cheers,
Tommy

mitsos said:

very simple circuit but the trafos are very important, and I hear difficult to wind.  Originals were probably wound by Reichenbach

Click to expand...

Langevin wound everything in-house during that era.  Mr Reichenbach may have had something to do with it as an employee or contractor. 

Colin,

I just got my kit and I started building it during my free time at FOH. The schematic and the BOM shows a C8=10nF and R64=270R, but in the color book instructions, there is no step where either of these are soldered. Also, there were only 1 of the 270 ohm resistors (bag was also labeled as quantity of 1) and no 10nF capacitors. I can only deduce that these are not needed and the instructions just haven't been updated, but I don't want to assume anything.

I will say this is a very well put together kit. All the resistors were individually bagged, labeled and even the leads were pre-bent and trimmed perfectly. The PCB is also very high quality and the solder pads are very sturdy. It's not quite as easy as putting together one of Jeff's VP2x/312 modules, but it still goes together quickly. A great kit for beginners and for touring guys who need something to do in order to remain sober. Excellent work, Colin!

Thanks!

Paul

So I finished assembling it without R64 and C8 and it seems to work great. Couple of observations I have are that the width of the faceplate and the height of the output transformer require all of the intended space for the 500 series slot. Adjacent modules in my little lunchbox had to have the mounting screws loosened so I could make the ezAM16 fit. There is clicking sound that corresponds with the stepped switch when turning up the gain. I do not know if R64 and C8 would help with this. But it is very quite, even without adjusting R46 per the instructions, as I have to wait till I get home because that is where I left my extension jig. And I'm too lazy to rig something up out here on the road.

Again, great kit, Colin!

Paul

Wiper noise clicking is probably unavoidable.  It's a fixed gain amp with a stepped pad in front of it. 

Anywhere I could listen to samples/shootouts with these?