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Laurence T

COS-11D SMQV transmitters gain issues

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Hi all,

 

I just purchased 2 more COS11D mics, this time wired for my recently purchased lectrosoncis SMVQ transmitters. I chose the universal wiring option as I may need to use them with older lectro transmitters.

 

However I’m experiencing some issues with transmitter volume/sensitivity when attempting to set up the optimum gain structure. In order to ‘tickle’ the -10 led I have to have the transmitter gain at maximum (44) and shout very very loudly. In fact, relatively normal interview talking volume rarely hits the green of -10.

 

Is this because I should have perhaps opted for the servo wiring? Or some other issue?

 

I definitely do not have the red dot versions (unless something untoward has happened) so am confused. Any help would be greatly appreciated!

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Thanks for all your input guys, I’m also of the opinion it’s an error in wiring. I just can’t quite believe both mics have exactly the same issue, although as they are both from the same supplier maybe I can. So frustrating.

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The best wiring for the COS-11 to Lectro TA-5 is as follows. The white wire and the ground wire goes to pin 1, the black wire goes to pin 3, jump pins 2 & 4. Guaranteed to give you more gain than you can ever need.

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Just to be clear, I didn’t wire these (I’m terrible at soldering!) - I bought them terminated for Lectro from the store. I guess I should just return them.

 

EDIT:

I have noticed TA5F - UNLE written onto both boxes, UNLE seems to correspond to the reduced sensitivity version serial on B&H. If i’m correct I think they may have sent my the incorrect microphones!

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Thanks Larry - that makes a lot of sense. 

 

Strange thing is when i google the Sanken model number with the UNLE suffix, it seems to mostly bring up he reduced sensitivity versions.

 

I can’t for the life of me think what else could be causing the low gain on the Tx. Really do have to shout in order to light up the -10 led and audio level is on 44!

 

On further research, the Sanken product codes for the different wiring seem to be as follows:

 

Lectro TA5F normal sensitivitiy: SAN-11DWNBKSMLE (is this the servo wiring?)

 

Lectro TA5F Reduced sensitivity: SAN-11DWRBKUNLE (The code on the mics I have been supplied)

 

Sennheiser LEMO normal sensitivity: SAN-11DANBSE

 

Sure TA4F normal sensitivity: SAN-11DANGYT4SH

 

Seems that I may have the red dot version?

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Reduced sensitivity functions are built into the mic not the connector. The Sanken reduced output versions are 10db down from the regular versions regardless of what connector is attached.

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41 minutes ago, Eric Toline said:

Reduced sensitivity functions are built into the mic not the connector. The Sanken reduced output versions are 10db down from the regular versions regardless of what connector is attached.

Indeed, and even though my mic does not have the ‘red’ band - the model number written on the box does correspond to Sankens  reduced sensitivity model number as seen I this picture. I realise thanks to Larry that UNLE is universal lectrosoncis, but also I’ve noticed on the Internet that the code only appears on Sanken models with reduced sensitivity. 

F41E1A89-A007-462B-80E4-6E946D2FF23C.jpeg

0187E0BF-AE58-4B3E-8242-D1F06AEB4A0B.jpeg

89D2B5E8-AA0A-4F12-A3E2-6E0A2C8E06B7.jpeg

D13E4681-EBF1-41F5-8B37-D39FF8ECFFE9.jpeg

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I had exposed the connecter and have found the following. Could anyone perhaps tell me if this is correct? 

 

Pin 1 -white (audio?) to a resistor, and another wire I think is the shield

 

pin 2 - 4 jump

 

pin 3 - black (bias?)

 

this seems to match up with fig 5 in lectrosonics wiring diagrams.

 

 

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5 minutes ago, jason porter said:

That is the correct universal wiring.

Thanks, it does seem to be. This is so odd.

 

 

So I have the lav in mid chest position, and when speaking at normal conversation volume, with a Tx audio level of 40(!) I only occasionally light the -20 led green.  

 

When I shout I’ll light the -10 green. I really have to go crazy to get them to go red and just hit the limiter (which is fulll modulation and optimum gain structure correct?)

 

Having the Tx audio level at anything less doesn’t even light the LEDs at all.

 

Am I missing something on my Tx?

 

 

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Just now, jason porter said:

Maybe the resistor is way bigger (more resistance!) than in should be? Effectively, padding the signal?

That would make sense - is the resistor thebonku thing that makes it ‘universal’?

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From Larry F -

 

'Smaller resistors give proportionally more gain. 2k is 6 dB more gain than 4k and 1k is 6 dB more again.'

 

They recommend a 1k on the wiring diagram...so if they used a 4k resistor by accident, that would be -12db ( I think!). Imagine if they used a 10k by mistake!

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Something is not right. I would send it back and get them re-wired or replaced by the store.

I usually keep my SMQVs with COS11D wired universal Lectro at level 16. That gives me enough gain for pretty much anything. If someone is soft spoken, I may up it to 18-20.

For reference, running the same SMQVs with DPA4061, I usually have the level anywhere between 30 to 36 for similar output.

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Thank you for all your help guys, really appreciate it.

Just now, ryanpeds said:

And that's why I normally don't buy through B&H

It actually wasn’t from B&H!

Am I right in thinking that if I remove the resistor completely, and attach the white wire straight to pin 5, it will be the correct (and non universal) servo bias wiring?

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