Sugar Cube speaker without enclosure

[M. Matthews]

There is a small loco that I wish to give the HM7000 treatment. Room is extremely limited and after assessing the space, it looks like I can only fit the speaker without an enclosure. Does anybody have any experience of what the resulting sound quality might be like?

Thanks

[SteveM6]

Short answer - it will sound terrible. They are designed to work with an enclosure.

[M. Matthews]

I thought as much. Thanks anyway!

[My name is Bond]

You receive an assortment of speaker enclosures with the sound decoder. Maybe one could be used or modified?

[Rallymatt]

Someone has 3D printed a super small enclosure to add sound to a TT:120 Class 08 shunter.

You could test a speaker without an enclosure just to confirm it is not desirable.

[Fishmanoz]

Any detail on how they did that Rm?

I’m assuming an -8TXS with the plug cut off and 6 pins terminating the appropriate cables. But then where is it fitted, let alone the speaker.

[Rallymatt]

Fishy, here is YT link

Quite inventive although long term the smaller motor clips could be an issue, depends on the properties of the 3D print resin.

[96RAF]

A pity we don’t have any TT120 service sheets to refer to.

Could not the larger clip seen in the video just be cropped shorter to match the new print items, thus providing space.

The Hornby speaker drives from both sides apparently so an enclosure is essential to separate the sound phasing.

[Fishmanoz]

Thanks Rm, interesting.

He’s using a Zimo MS500N decoder at 14x10x2.6mm 6-pin which will fit into the socket in the 08 with the challenge being the speaker (added this to avoid having to go the YT to get that detail). It’s around the same price as the -8TXS which is much larger at 18x10x7mm. You could always put the speaker in a wagon behind.

[Rallymatt]

There is an updated video with more of what Richard has done to achieve this.

In addition to your idea of trimming down the motor clip Rob, I would think it could be possible to cut down the smaller speaker enclosure too or make one from plasicard, for those of us without a 3D printer 😁

Although, making a new motor clip does mean you have an option to return to original if you needed to. I would be more keen to get a stay alive in there though, ahead of sound.