Lectrosonics SMB/DPA issues

[Conor998]

We are using lots of 4071's on tv drama's here for the last 5 years.

 

The 3056 adapters are working perfect with lectro sra's and uma's.

 

Tried and Tested.

[Henry the RFS Wireman]

Reading these thread has prompted me to join the JW Sound forum.

 

So firstly to clear up some speculation. Correct, here at Richmond Film Services we do not have any Lectrosonics to hire. When Lectrosonics products began to increase in popularity, I started to accept my clients personal wiring requests on the proviso that they check the microphones on their transmitters as soon as they receive them back from me. I do have a personal microphone power supply on my bench which delivers a positive bias voltage to the commonly found connectors on most radio microphone transmitters to give me an indication as to whether I have the wiring correct. But I have always said that there is no substitute for checking the personal mics with the transmitter. Also, please bear in mind all I do is wiring, I do not get out in the field like you guys, so I rely on feedback and constructive criticism to deliver my service to you.

 

Secondly, for DPA microphones into Lectrosonics transmitters I have always followed wiring scheme #3 and fitted a 3K3 ohm resistor (in the early days I fitted 3K9 resistors, but have found 3K3 ohm resistors more useful to keep in stock, as they can double up for wiring scheme #1). The exceptions being personal mics for Tim and Tom (mentioned above) who prefer 1K7 ohm resistors, and now it looks like Seb will prefer that too. He will be returning his mics to me shortly to see if this solves his problem. I have terminated scores and scores of DPA mics for use with Lectros. How is it I haven't had more returned to me?

 

Thirdly, I always use the Rean connector, unless the client supplies me with something else. The Reans are what I hold in stock.

[LarryF]

Reading these thread has prompted me to join the JW Sound forum.

 

So firstly to clear up some speculation. Correct, here at Richmond Film Services we do not have any Lectrosonics to hire. When Lectrosonics products began to increase in popularity, I started to accept my clients personal wiring requests on the proviso that they check the microphones on their transmitters as soon as they receive them back from me. I do have a personal microphone power supply on my bench which delivers a positive bias voltage to the commonly found connectors on most radio microphone transmitters to give me an indication as to whether I have the wiring correct. But I have always said that there is no substitute for checking the personal mics with the transmitter. Also, please bear in mind all I do is wiring, I do not get out in the field like you guys, so I rely on feedback and constructive criticism to deliver my service to you.

 

Secondly, for DPA microphones into Lectrosonics transmitters I have always followed wiring scheme #3 and fitted a 3K3 ohm resistor (in the early days I fitted 3K9 resistors, but have found 3K3 ohm resistors more useful to keep in stock, as they can double up for wiring scheme #1). The exceptions being personal mics for Tim and Tom (mentioned above) who prefer 1K7 ohm resistors, and now it looks like Seb will prefer that too. He will be returning his mics to me shortly to see if this solves his problem. I have terminated scores and scores of DPA mics for use with Lectros. How is it I haven't had more returned to me?

 

Thirdly, I always use the Rean connector, unless the client supplies me with something else. The Reans are what I hold in stock.

Hi Henry,

Your values are certainly in the ballpark for good performance with the DPA's. Please let us know what you find with Seb's mics. This problem has been very curious.

Best Regards,

Larry Fisher

Lectrosonics

[Simon Hayes]

Henry at Richmond Film Services has wired all my DPA 4071 lavs that I use with Lectrosonics SMB transmitters and there has never been a mismatch.

[Stuart Piggott]

Henry's wiring would be the last thing I'd look at. Over the years he's wired everything from lavs to my sound cart and I've had zero issues

[Simon Hayter]

+1for Henry. Never had a problem

[sergiofucchi]

With this DPA adaptor I have no issues....

 

[LarryF]

 

With this DPA adaptor I have no issues....

 

Hi Sergio,

That adapter will work just fine on the older Lectros but not for the servo input units. The DAD6021 is all wrong for the UM400a, LMa and Sm series.

Best,

Larry F

Lectro

[Math]

I just want to chime in with the fact that Henry has rewired every single one of my current set of lav mics; DPA 4060, 4071 and Cos-11's, as well as numerous repairs of varying complexity and i have not once had cause to complain or return anything. His work is excellent. 

[sergiofucchi]

Hi Sergio,

That adapter will work just fine on the older Lectros but not for the servo input units. The DAD6021 is all wrong for the UM400a, LMa and Sm series.

Best,

Larry F

Lectro

 

But with my SMDB/E01 this works fine with DPA 4060 and 4071....

[sebblach]

Thanks for all your responses guys. Just to clarify, I've tested mics both hardwired and with the appropriate adaptor (dad3056) with the same poor results. I have never used the 2021 adaptors.

I'd also like to mention that I've never been anything other than happy with the work Henry at rfs has done for me. The fact that I'm having the same issues with brand new mics that are yet to be rewired suggests to me a problem other than wiring. The mics will be going back to Henry this week to try a lower value resistor, although I'm not entirely sure this will solve the problem.

I'll post the results as soon as I've tested them.

Thanks again.

[rich]

where are you based Seb?

i think it would be easier to trouble shoot if Henry had your entire system in front of him. and certainly quicker to see if things work or not.

and sorry of thats volunteering you for additional work Henry.

[sebblach]

Hi Rich, I'm London based, I'll be taking my whole bag in this time! Cheers.

[rich]

sorry, knew you were london based as well from your posts as it lists your location on the left. 

meant which part of london.

 

but yes, if you bring your rig along, then Henry has a fighting chance of helping you find where the problem lies.

[sebblach]

Hi guys,

 

I took my bag in to Henry last week, sadly we couldn't get to the bottom of the problem. We tested the resistor values that Henry had fitted last time at 1k7. We double checked his work against the recommended wiring and are both happy that this is absolutely not a wiring issue, I have the same results with the recommended DPA adaptors (3056) as I do hardwired. Henry has wired up 100s of DPAs with no complaints, so the wiring was never in question for me. My DPA4071s have been back to DPA and been given a clean bill of health, reterminated with microdots, and still sound bad through my lectros.

 

The problem is that I just can't get enough level into my tx. According to the manuals, I should be setting levels on the tx so the first red l.e.d. occasionally reads the peaks. With my tx on full (44) I have to shout to get the first l.e.d. to turn red. I have 4 transmitters and have tested through all of them, so it's unlikely a fault with the tx. I asked a few of the guys on facebook groups this week what sort of gain settings they regularly used on their transmitters and the average answer was 20-25. With all my mics (tr50/kat66/cos11) I seem to be having to run them much hotter (35-40) to get decent signal to noise ratio. 

 

Any more thoughts anyone?

[studiomprd]

" Any more thoughts anyone? "

have you offended your Deity ?

CRAP happens ??

 

maybe you should get ace problem solver Larry F on the case...

send him a mic-TX set at the Secret Lab in NM, USA...

Or the appropriate local region SPA...

Edited September 25, 2013 by studiomprd

[LarryF]

Hi Seb,

I'd say send the transmitter and mic to me to get it looked at but that's a lot of water to cover. Not knocking Henry, but take the stuff to Pyers at Raycom. A second set of eyeballs can sometimes find a problem in a few minutes if not seconds. At least it works like that around here. Pyers has all the schematics, other transmitters, etc., to try to nail this problem down. When we duplicated your setup, we had good gain at 4k (our recommended value) with that model mic and the 1.7k that is installed should give you 6 dB more output.

Best Regards,

Larry Fisher

Lectrosonics

[sebblach]

Thanks Larry, I've arranged to pay Pyers a visit next week. I'll let you know how I get on.

 

Best,

 

Seb

[LarryF]

Thanks Larry, I've arranged to pay Pyers a visit next week. I'll let you know how I get on.

 

Best,

 

Seb

Hi Seb,

I will be very curious.

Best,

Larry F

Lectro

[sergiofucchi]

Contrary to what was stated by Larry Fisher and from what is written on the website of the DPA, I continue to say that your problem is that the correct adapter is not the DAD3056 but the DAD6021 that provides the right level of input to the SM series.

 

So it is for me and so it is for all those who bought in Italy and use the DPA 4071/4060 with the transmitters of SM series. You should do a test with a DAD6021.

 

 

Sergio.

[sebblach]

Hi guys. Here's an update.

After several months of trying to get to the bottom of this I feel I've made some progress. I've tested DPA mics (all models, hardwired, and with microdot adaptors) on 5 separate block 606 srb systems. All with the same poor results. With the 411 and venue receivers, the DPAs sound as they should. Also, on a US bought block 24 sra, sounded as they should.

I'd really love to hear from anyone running block 606 srb receivers with DPA lavs who's getting good results.

Cheers guys.

[karlw]

Hi Seb,

 

Based on your latest post, we have been able to draw some conclusions about why you are probably experiencing these results.

 

We believe that your SMb transmitter/s are set to North American Hybrid (400) mode which is not correct for use in the UK. Our evidence for this is that your SMb transmitter works fine with a US spec SRa receiver.

 

As it turns out, we ship all UCR411A units with the default compatibility set to 400-NA (North American) mode. Our guess is that the 411A you used for testing is still set to this mode, and thus works fine with your SMb transmitter/s. As a side note, we will be changing our procedures so that any 411A shipped to Europe will be set to HBR-EU mode.

 

The SRB/E01, however, is set to HBR-EU mode, which is the default setting when shipped. Because of the difference in RF deviation specs between the NA and EU versions, you are hearing a distorted signal from your SRb receivers.

 

One way to test for this is to go into the menu of the 411A and change the compatibility from 400 NA to HBR EU. After you have done this, you should have the same (distorted) sound with the SMb + UCR411A combo as you have from the SMb + SRb/E01 combination.

 

You have two options:

 

1. Re-set your SMb transmitter/s to the HBR-EU mode. This is the proper mode for EU operation because of your local regulations. You may be able to do this in the menu if all modes have been unlocked. If so, select HBR mode. If all modes have not been enabled (i.e. if the unit only shows the North American modes like 400, Mode3, 200, etc.) you may have to have a servicing dealer convert it back to EU spec or unlock all modes.

 

2. Have the North American firmware put into your SRb receiver/s. This can be done at a servicing dealer.

 

Once either of these operations has been done, you should have good results from these systems.

[TJW]

I'd really love to hear from anyone running block 606 srb receivers with DPA lavs who's getting good results.

 

Hi Seb,

 

I hope that you have the answer to your conundrum in Karlw's response. I am using EU spec SM transmitters with a Venue receiver for the first 6 and an SR for seven and eight, linking in to the RF out from the Venue. For a year now - and that is working on two feature films and a TV series - I have mixed and matched between Venue and SRbs and I detect no fundamental difference between the performance of the two receive systems. If the problem is as highlighted in Karlw's reply, it is interesting that the open and natural sound of the DPAs highlights the problem whereas the Cos-11s or the level settings used with the Cos-11 tend to mask it? You have my contact details. Call me if I can be of assistance.

 

All best

 

Tim

[RPSharman]

Karl,

I have Venue with 606 modules. My Venue does not have HBR as an option. Will they work properly? I haven't really tested them, since I'm not using 606 until I move to the UK at the end of next year.

Robert

[karlw]

Answered by PM as well. It depends on if you are planning to use E01 (EU spec) transmitters. If so, then you'll need HBR mode (400 mode with EU specs) otherwise you will lose about 6-8 dB of s/n. You can load the E01 firmware into your VR frame to get those modes.