Hello, I have had problems with my last couple sound installs in Atlas locomotives. My first attempt was in an Atlas GP38 with very good results. I used a soundtaxx tsunami and a small oval speaker and encloser. I mounted the speaker in the rear of the loco on top of a milled down weight. The sound is great very clear and good volume.
The next two installs I did were in an Atlas GP40 and a U23B. Both resulted in a very crackly speaker sound. I tried turning the volume way down and still had the crackling. Its alsmost like the speaker is getting to much power? but its the same setup as the other loco. Only difference is that I removed the rear weight altogether and glued the speaker in the top of the loco body facing downward. I suspected a bad speaker so I ordered some new ones(QSI small oval) with the same result from multiple speakers. They are 8ohm 1 watt speakers whichI believe are appropriate for tsunami. Sorry this is so long but I am stumped. Thanks
I agree. Bad idea on mounting to the shell. It’s very light and has a bunch of details, etc attached that are prone to buzzing, humming, and rattling – and not in a good way.
If you mount the speaker to the chassis, it’s heavy and resists this sort of thing.
You didn’t mention whether or not the speaker on the latter two locos is in an enclosure. That will also help with sound quality – a bunch – but again shouldn’t be attached to the shell.
I’d double check the soldering of the wires, it can happen that a little bit of solder can bleed over (on the speaker) to the other post where the other wire is connected, causing a short that doesn’t have enough power going thru it to register as a short circuit, but causes distortion.
I have installed 16mm x 35mm speakers into home made styrene baffles and slipped them up into the shell and they work fine in a HO 44 ton and HO 70 ton.
The same speakers in larger diesels over the rear truck with no baffles. Also 28 mm round.
Thankyou for the repies. The speakers on the second two are in enclosures. Also to check if it was the shell i removed the shell and the speaker from the shell and let it idle and blew the horn with the speaker/encloser loose and in my hand. The cracking is definately coming from the speaker. I’ll check the soldering next. Also it is the drop in atlas style board with all connections soldered.
Check the cone of the speaker to make sure it is not deformed or has any metal pieces stuck to it. The cone may have gotten deformed while you handled it. If it is deformed, you might be able to get it back in shape. Put some sitcky glue on a finger,not too much, and gently press the cone, then gently lift your finger up and off the cone. It might spring back into shape. I did this on one of my speakers. Joe
OK, does sound more like the speaker is part of the issue. Still a better idea to mount the speakers to the chassis.
I know some of the OEM Tsunamis don’t have the equalizer as part of the package. I’d check to see if yours does. If so, finding what range the funky sounds are in and adjusting the EQ to cut those freqs down might help.
Could be an over-driven speaker. I damaged a few speakers with similar results from not first turning down the volume from the factory default maximum setting. I’ve since gotten in the habit of turning the volume down to at least 50% before ever trying it.
That is why I recommended the reset. It is possible to adjust the EQ so much that the math on the soundwave causes the soundwave to distort or clip. The sound is distored mathematically before it enters the amplifier. So no matter how little or much you turn it up, it’s still distorted. So a reset would give you an even level EQ (in fact it would turn off the custom EQ)
Thanks again everyone for the replies. After considering all the responses and doing a bit more reading elsewhere. I decided to give the tsunami equalizer a try. For my first attempt I selected one of the preset equaliser options that sound traxx specifies for different speakers available. I selected the small speaker option since I use a small oval. It made an imediate and very noticible improvement. I think I can still detect a small bit of cracking under certain circumstances so I may try doing some custom adjustments but I think this may be the the solution. Thanks again for the replies.