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Have you asked the manufacturer? Not being familiar with the product, I would say to look in the instructions, or ask MTH, or take the cover off and see if there's a volume control inside. If not, it's easy to reduce the volume with a couple of resistors or a potentiometer.

There are things to ask MTH, if there's no built-in way to reduce the volume. You need to ask what impedance the speaker is, for starters. I'm sure that they have an engineer at their HQ who can give you the answers.
Like I said, you need to do this scientifically. You need to find out the impedance of the speaker circuit. The speaker may be marked, or you can ask MTH. Then you need to use a potentiometer, wired as such, (three connections) not wired with two connections...that's a rheostat...

Using a potentiometer that has a high impedance wired as a rheostat, will not significantly reduce the speaker signal, and you will probably not even notice any reduction in volume.

You need to create a voltage divider circuit---that's what a pot does...and you will then have a linear volume control that will allow you to do an infinite adjustment.

Once you know the impedance of the speaker, we can continue and you'll be satisfied.
Trying to drive a low-impedance loudspeaker in a potentiometric configuration isn't a good idea. The potentiometer value would need to be lower than the impedance of the loudspeaker, and that would add additional load to the amplifier.

If you make the potentiometer value high, you essentially wind up with a rheostat because not much of the current will flow through the bottom leg of the pot.

A potentiometer with a resistance of about 20 ohms connected as a rheostat would give at least a 10 dB control range with an 8 ohm speaker. The pot must have enough power handling rating to carry the speaker's current - probably a minimum of 1 watt.
quote:
Originally posted by Dale Manquen:
Sam, I doubt that the amplifier cares what the load impedance is as long at it is no lower than the original speaker load.
True Dale, just the engineer in me musing over what it should be over reality. Doubt the amp chip really cares what the impedance is unless shorted wires and even then probably has some protection. So any low value pot would work as a voltage divider.

Wally,

 

I hope this helps

Connect A - to transformer AC (Positive)

also Connect A - to one side of activation button (NOTE: you need 2 wires on A)

Connect B - to transformer AC (Ground)

Connect C - to other side of activation button

Connect D - to transformer AC (Positive)activationbutton

Connect E - to transformer AC (Ground)

 

D & E control the lighting

 

A-B-C control the mechanism

Originally Posted by Dennis S:

Wally,

 

When using Lionel type power supplies the terminal marked - U - is the common or ground terminal.

That's not universally true. Specifically, for the 1033, the U terminal goes to the center rail.  If not, the whistle will ring the bell instead.  There are a couple of other PW transformers that are wired that way as well, but the numbers escape me right now.  I happen to have a couple of 1033's here, so I know that one for sure.

Originally Posted by gunrunnerjohn:
Originally Posted by Dennis S:

Wally,

 

When using Lionel type power supplies the terminal marked - U - is the common or ground terminal.

That's not universally true. Specifically, for the 1033, the U terminal goes to the center rail.  If not, the whistle will ring the bell instead.  There are a couple of other PW transformers that are wired that way as well, but the numbers escape me right now.  I happen to have a couple of 1033's here, so I know that one for sure.

Another one is the TW.  (Happened to have one under the desk from when I updated a sound file recently )  U is the center, A is common.

 

-Dave

Based on my experience...put a piece of tape over the speaker opening. Cover as much as you want to reduce volume. That is how the old Victrolas did it. Open the door to increase sound, close as much as you want to make quieter. If the other guys hate it just cut the wire. Keep it simple. Chances are no trips for parts, you most likely have a piece of tape. 

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