LGB Black Box sound unit - quick question....

[Zerogee]

Hi all,

A fairly basic question that I THINK I already know the answer to, but thought I'd ask for other opinions on here before I b*gger something up....
I have a spare LGB "black box" all-in-one sound unit, the Euro Diesel type, that I'm planning to use in the factory-MTS 251 Pressnitztalbahn blue diesel. Now, I know from previous threads that it's quite acceptable to open the black box up and remove the circuit board and speaker from the case, in order to mount the speaker where it will work best - but is it OK to swap the speaker for a larger one of the same ohm rating?
I'm assuming that the sound unit will only deliver whatever wattage it is capable of, provided the speaker impedance is correct?
Can anyone confirm that the speaker used in the "black box" unit is an 8 ohm type as used by Massoth in everything else they make for LGB?

Thanks!

Jon.

 

[nicebutdim]

Not sure what rating maybe in there but yes it is ok to up the speaker size as long as the impedance matches. You 'may' lose a little volume but nothing drastic.

 

[Gizzy]

Why not mount the 'Black Box' above the location for the speaker in the chassis John?

It'll work just as well. You might also find a hole for the volume pot in the chassis, close to the fuel tank and accesible from between the bogies when on the track....

 

[Zerogee]

I had considered that, Giz, and might still do it IF there is a suitable space when I take the loco apart - depends where the weights and the MTS board are located. There is always room for a speaker, but LGB have a habit of putting other stuff in the way so that mounting the whole box is tricky - on my orange-and-cream whizzy-cranks 2095, the speaker has to be tucked halfway under one of the weights, severely restricting the type of speaker that can easily be fitted.
This particular black box that I have is an older one, with the volume pot integrated into the circuit board rather than the external one on wires like the newer type. Normally I wouldn't use the LGB sound units at all due to their horrendous prices compared with other stand-alone sound units such as the S (when you can get one!), but I just happen to have a couple here (one diesel, one steam) that I stripped out of other locos, so I may as well use one in the 251.

Will make my final decision when I get the body off the new loco!

Jon.

 

[Philbahn]

If I remember right they are 8ohm , so any speaker of that range would do.
I use Visaton from Impact Audio Crewe FRS8

 

[Gizzy]

There is a space for a speaker/sound unit in the large hood.

It's quite obvious when you open up the loco jon....

 

[Zerogee]

There is a space for a speaker/sound unit in the large hood.

It's quite obvious when you open up the loco jon....

Thanks Giz - I know the layout of the old-model red V51/52, 'cos I've done an XLS install in one of those, just not 100% sure if they've changed anything internally for the new blue 251 until I actually get inside! Hopefully as you say there will be the same big space as the old one.

Jon.

 

[beavercreek]

Hi Jon I have opened up a few of them and added larger speakers. They will work with 4 or 8 ohm jobbies.
You will know that they can be set to the same loco address as the DCC board in the loco.

I used my ones on DC but will be combining them with some DCC decoders for future projects.

 

[Brixham]

Sorry to hi-jack this....

The mini conectors on the side of the black box..these are for the whistle/bell/horn function, also the wheel tacho....

But what type are they? They look like 0.05 inch pitch

And while we're at it...the connector type for the power buffer ( I do have a diagram for the buffer...courtesy of somwhere on this forum... ) .

I do have access to RS and Farnell

Malcolm

 

[Zerogee]

Malcolm - I think they are all standard miniCT connectors as used by Massoth - Mark (Muns) can supply them with leads fitted:

http://www.gardenrailoutlet.co.uk/minict-cable Jon.

 

[Railway42]

Hi.
As a reply to your post the speaker must be 8 ohm, but the thing to watch is the wattage. You want 2 watt or more to give you the best results. DO NOT use a 4 ohm speaker as this will draw twice the current through the amplifier. If you use a 16 ohm the volume will drop but it wont harm the amp. So to get a better sound it is not just the size but the type. To get some idea look at the Massoth.de site it is in English
plus they sell the plugs for the LGB sound unit and you can order direct.

Alan

 

[Tim Brien]

As stated, the original speaker is 8 ohms. I definately would not go with a single 4 ohm speaker as you will over drive the sound board amplifier and let the expensive smoke out. Two 4 ohm speakers in series (total 8 ohms) could be used but I cannot see any advantage over a single decent 8 ohm.

The stock LGB mylar cone speaker found in the black boxes is prone to failure so I have sourced aftermarket speakers to replace any failed units. My recommendation is the 3 watt Massoth speaker around 50 -60mm diameter. This gives far better bass response than the slimline 2 watt speaker fitted standard to the black box.

 

[beavercreek]

The reason why I said 4 or 8 ohm is that I have used both with the LGB modules (what speakers I had to hand at the time) and there was no problem so I can only pass on what I have experienced.

 

[Brixham]

Thanks Zerogee..connectors ordered and now arrived.

Malcolm