dukasound

Langevin AM16 on my bench!!!
« on: April 02, 2005, 10:21:13 AM »
Hi Langevinians :sam:
Langevin is on my bench :grin:

After about three months I received AM16 :grin:
I resoldered a couple of wires and IT WORKS. All parts are original. Transistor Q1-Q6 are 2N5210 and I suppose Q7 and Q8 are 2N3053. Both input and output transformers I connected to 600ohm. Now I use «Low Power»..
On PSU I saw 24,3VDC. Checked voltages who is higher than in manual (maybe with «High Power» will be lower).

Then I adjusted balance. Because I havent distortion meter I check with simple method. I adjust trimmer for zero voltage beetween emiters of Q5 and Q6.



A little crash on AM16 face :sad:

Also I make and chech a Joe' input pad. It works very good.


Sound is nice and FAT. I compare AM16 and my dbx286A (bypass compressor,etc) and it sounds much better.
Thanks to my best man Mickey from Chicago who bought this for me and Joe for suggestions about input pad and other dilemmas.
Duka


Langevin AM16 on my bench!!!
« Reply #1 on: April 02, 2005, 10:28:30 AM »
Congratulations, Duka! I bought a pair of these a few years ago. I really like the sound. Very thick with a smooth, mellow top end.
Regards,
Scott

dukasound

Langevin AM16 on my bench!!!
« Reply #2 on: April 02, 2005, 10:50:26 AM »
Quote from: "scott_humphrey"
Congratulations, Duka! I bought a pair of these a few years ago. I really like the sound. Very thick with a smooth, mellow top end.
Regards,
Scott

Thanks Scott
Did you checked voltages and do you have some input pad?
Duka

Langevin AM16 on my bench!!!
« Reply #3 on: April 02, 2005, 11:21:59 AM »
Quote from: "dukasound"
Thanks Scott
Did you checked voltages and do you have some input pad?
Duka


I built a fixed pad (~ -20 dB) that I can switch in and out. I like the way you and Joe did it, though.

I don't have a distortion meter, either, so I had to adjust based on voltages like the manual said. As I recall the voltages were fine and I didn't have to adjust anything. I did put some attenuators at the output.




Am16 New
« Reply #4 on: April 02, 2005, 11:41:48 AM »
I have DIY circuit boards for the AM16 , send me a email if your interested.
« Last Edit: January 31, 2019, 03:37:10 PM by electrochronic »
curiousaudioparts at  gmail  dot  com
https://sites.google.com/site/diypartsstore/

chrissugar

Langevin AM16 on my bench!!!
« Reply #5 on: April 02, 2005, 11:50:39 AM »
Hey Scott

Very nice box. I love those red knobs. Who make them?
Where can I buy some?

chrissugar
Christian Mike Sugar
        CMS-LAB

Langevin AM16 on my bench!!!
« Reply #6 on: April 02, 2005, 12:16:13 PM »
Quote from: "chrissugar"
Hey Scott

Very nice box. I love those red knobs. Who make them?
Where can I buy some?

chrissugar


They're Daka Ware knobs. I bought them from http://www.leedselect.com/parts-knobs.html. I just ordered the last two, though. Sorry. The guy that I talked to at Leeds Electronics said that they used to have hundreds, but apparently these went fast. You might try checking eBay.

jensenmann

Langevin AM16 on my bench!!!
« Reply #7 on: April 02, 2005, 03:04:22 PM »
maxwall, there was another thread where you can find  at least pdfs for etching.
http://www.groupdiy.com/index.php?topic=2672&postdays=0&postorder=asc&highlight=langevin+am16&start=0
CJ finished some and was pretty satisfied with the result. He also used the Sowter trannies.
The input attenuator is probably imedance-matched to the Zin of the input tranny, an output pad should be impedance-matched to the Zout of this trannie. In this case you can maybe use the same pad for in- and out, depending on how the trannies are soldered. But you should have a inputpad for preventing the input from overloading .
Jens
Jens
Quote from: PRR
The tubes of course don't care what frequency they distort

dukasound

Langevin AM16 on my bench!!!
« Reply #8 on: April 03, 2005, 09:15:24 AM »
Nice pots Scott :thumb: . What kind :?:
How did you fix AM16 on chassis?
I measured voltages with High Power

Duka

Langevin AM16 on my bench!!!
« Reply #9 on: April 03, 2005, 09:51:04 AM »
Quote from: "dukasound"
Nice pots Scott :thumb: . What kind :?:
How did you fix AM16 on chassis?
I measured voltages with High Power

Duka


I used Daven attenuators (model # laq-350-g). The are 600ohm/600ohm attenuators.

I used the high voltage configuation, too. I used to have an original manual for these, but unfortunately I moved recently and the literature I have is packed in a box somewhere in my garage.


Langevin AM16 on my bench!!!
« Reply #10 on: April 03, 2005, 09:56:53 AM »
Quote from: "dukasound"

How did you fix AM16 on chassis?

Duka


I used silicon sealer, the stuff that you can by at automotive stores. I was careful not to let the chassis of the AM16 contact the rack chassis (to keep the ground loops away).

matthias

Langevin AM16 on my bench!!!
« Reply #11 on: April 03, 2005, 09:57:19 AM »
@  scott:

that looks really professional !!

how did you do the panel labeling ??
is that somthing like a printed clear foil or a real print...??

mat

Langevin AM16 on my bench!!!
« Reply #12 on: April 03, 2005, 12:24:45 PM »
Quote from: "matthias"
@  scott:

that looks really professional !!

how did you do the panel labeling ??
is that somthing like a printed clear foil or a real print...??

mat


Thanks, Mat!

The labels are from my deskjet printer. I bought some silver, metallic stickers and printed onto them, then I coated them with spray lacquer. It's not very durable, however, but it's good enough for light use in the studio rack. Future projects will be done with front panel express.

soundguy

Langevin AM16 on my bench!!!
« Reply #13 on: April 03, 2005, 05:24:08 PM »
sharp looking project scott!


dave

chips are good with dip...

Rob Flinn

Langevin AM16 on my bench!!!
« Reply #14 on: April 03, 2005, 08:24:50 PM »
Quote
Scott


I used the high voltage configuation, too.


Just a small point but if you have these mic amps set for +24dBm operation the harmonic generation is greater by 0.25% than if you have them set for +18dBm.  Check page 4 of the spec sheet.
regards Rob

Langevin AM16 on my bench!!!
« Reply #15 on: April 03, 2005, 10:06:05 PM »
Quote from: "Rob Flinn"


Just a small point but if you have these mic amps set for +24dBm operation the harmonic generation is greater by 0.25% than if you have them set for +18dBm.  Check page 4 of the spec sheet.


Thanks for the info! Here's a link to the manual for anyone else who's interested:

http://www.geocities.com/ciminosound/langevin-am-16.html

Am16 New
« Reply #16 on: April 04, 2005, 12:37:14 AM »


« Last Edit: January 31, 2019, 03:38:43 PM by electrochronic »
curiousaudioparts at  gmail  dot  com
https://sites.google.com/site/diypartsstore/

Sleeper

Langevin AM16 on my bench!!!
« Reply #17 on: April 04, 2005, 01:28:01 AM »
hey Scott,
nice looking rack up.
I love mine, but my metalwork is so much better now, I'm thinking about a rerack, maybe add a few more bells and whistles as I do so.

What are those caps i see hanging off the connector?
a litle psu bypass/stabilasition?

Nice pics
Sleeper

JLM Audio

Langevin AM16 on my bench!!!
« Reply #18 on: April 04, 2005, 10:41:46 AM »
Remember the AM16 output must be loaded by 600ohms to keep the frequency response flat. If you do not load the output you will have a 1 to 3dB rise by 20kHz which rises to about 6 to 8dB at around 40khz. Doesn't sound much but in listening term it is the difference between warm or harsh.

Also if you are running into pro level recording A/D systems which take +18dBM to +24dBM to clip using an output pad will stop the output from actually reaching these levels without the AM16 clipping. So really all that is needed is a variable input PAD. To change the 20dB PAD shown on the previous page to a variable 45dB PAD change the 150ohm resistor to 10ohm.

Joe

www.jlmaudio.com
Joe

http://www.jlmaudio.com/shop
Capturing Audio without Injury

Langevin AM16 on my bench!!!
« Reply #19 on: April 04, 2005, 05:41:44 PM »
Quote from: "JLM Audio"
Remember the AM16 output must be loaded by 600ohms to keep the frequency response flat. If you do not load the output you will have a 1 to 3dB rise by 20kHz which rises to about 6 to 8dB at around 40khz. Doesn't sound much but in listening term it is the difference between warm or harsh.

Also if you are running into pro level recording A/D systems which take +18dBM to +24dBM to clip using an output pad will stop the output from actually reaching these levels without the AM16 clipping. So really all that is needed is a variable input PAD. To change the 20dB PAD shown on the previous page to a variable 45dB PAD change the 150ohm resistor to 10ohm.

Joe

www.jlmaudio.com


Great info, Joe. Thanks.


 

Related Topics

  Subject / Started by Replies Last post
2 Replies
1911 Views
Last post July 22, 2007, 02:37:42 PM
by EmRR
41 Replies
11754 Views
Last post February 17, 2016, 11:10:56 PM
by Whoops
22 Replies
6120 Views
Last post January 31, 2015, 04:45:21 PM
by Rob Flinn
1 Replies
637 Views
Last post April 28, 2018, 09:21:10 AM
by jensenmann