I have emailed Weber about the MASS dummyload and...

[zonta]

got this response:

Me: Is the element called "motor" just the magnet of a speaker as it is or
do you modify it in order to get better results?

Weber: It is the voice coil, spider, small magnet,  and voice coil wires. It is exactly like a speaker, unmodified.

http://www.webervst.com/mass.html



I think I will be buying a cheapey 50watt noname speaker and try to make my own dummyload out of it by removing the cone.

Wish me lock.  :roll:

[Dai H.]

I don't believe that your speaker w/out the cone will be the same (no movement). Why not just buy a MASS motor? They aren't that expensive.

[zonta]

Dai H., in theory, if his one is moving without any modifications, mine should also.

Yes the motor is cheap itself but, shipped to Europe, it won't be.

Any other comments?

[aron]

His motor is cheap and why do people think that USPS is expensive?

Not only that, Weber does it right.

Did you check and see how much it would cost?

I ship switches all over the world starting at a measley $2.

[John Egerton]

I was thinking of buying one of these....

If I was to purchase the 16ohm motor for the mass, would some of you guys help me to construct this thing?

Basically, I don;t want any fancy features, no treble/bass controls, just the function to set the level....

What would this involve?

Thanks..

John

[Peter Snowberg]

The schematic at the top of the topic is from Weber, so it looks like all you need are two jacks, the MASS motor, a 100 ohm 1 watt pot, and a 100 ohm 2 watt resistor. Looks pretty straight forward.

Adding the tone stack just takes four pots, 1 resistor, and three or four caps. Something to consider, but you could always add it later if you wanted.

Take care,
-Peter

[Mike Burgundy]

if you (or anyone) cuts up a speaker to use as a silent load, keep in mind you have to find a way to center the voice coil into the gap in the magnet/chassis. Under no circumstances should the coil be able to touch the gap wall, you should also allow for a bit of axial movement. Could be tough.

[Dai H.]

Dai H., in theory, if his one is moving without any modifications, mine should also.

Yes the motor is cheap itself but, shipped to Europe, it won't be.

Any other comments?

How about if you wait and ship it surface mail? What is it going to be for? Have you explored other ways of lowering the volume? Post-PI MV, etc.?

[Nasse]

I have no experience about dummy speaker loads and have stayed away from tube amps for some time, but who knows if I chance my mind...

But just thought that there may be a ready made product available that is just like what is described: a silent speaker with moving coil. Things like this are made for car stereo use or home cinema use. Look after such product as "bass shaker" or something. Such item is intended to be bolted under your TV chair or sofa or car seat. Feed it with your subwoofer and it vibrates direct your body, and gives the illusion of very powerfull bass. Or so they claim. I think there is some diy story around the net somewhere, try epanorama hifi and subwoofer links maybe.

But probaply it has drawbacks, I quess at middle and treble freqs this kind of gadget does not move just not at all, and resonance peak is tuned for heavy bass. So it may give different response than Celestion Blue speaker.

[zonta]

ok. how much do you think it would weigh? around 5 pounds? usps charges 26$ for a 5 pound weighing package.

Have you explored other ways of lowering the volume? Post-PI MV, etc.?

Dai H., can you explain a bit further mate?

[Dai H.]

= post phase inverter master volume

It's for amps like Marshalls where a lot of distortion comes from driving the phase inverter. So placing the master AFTER the PI helps you keep more of the sound while still being a master volume. I don't know anything about the Peavey 30, so there isn't much advice I can give you there.

[Bill_F]

What about the inline attenuators they sell? Are they any good?

http://www.webervst.com/load.html

I imagine that would be a pretty easy build.