Useful Electronics

As of the beginning of 2003 IWAC AB have started a small production of electronics of items that are hard to find elswhere.

Electronic Loudspeaker Guard LSP1

When your solid-state amplifier fails in the final output stage, the result is almost always that harmful DC current is beeing fed to your speakers, destroying them as well.

A fuse in serial may provide some protection against overloading, but does not protect against DC (DC=Directive Current).

These hand-built and individually tested units comes at a price that is not cheap, but compared to the investment of your more expensive loudspeakers, they can soon pay off!

Standard model LSP1 features:

• Practical boxes, screw or clamp them directly on the rear of the speaker.
• Rugged design, can take alot of punishment. Both physical and electrical, see data below.
• No external power supply needed.
• Double marking of input / output connections, label and permanent marking on box.
• Simple connection via push-spring connectors. These allows for pre-soldered wires.
• No demands on speaker impedance.
• Standard model for amplifiers with more than 30Watts output.
• LSP1a available for amplifiers less than 30Watts.
• Perfect for car audio as well.
• Automatic reset (no 'reset'-button needed).
• Manual included in price.

Technical data:

• Maximum relay break current: 10 Amps.
• Relay spark reduction with capacitor.
• Minimum protect voltage 10-12 Volts.
• Breakpoint DC current ~0.2 Amp.
• Maximum voltage 85 V.

Who needs them?

Depending on your equipment, you must calculate the possibility of a loss. If you have invested alot of money in your speakers and insurances cannot cover a loss; this is most probably for you. This becomes especially true for expensive vintage speakers. A loss there may not even be possible to recover!

Electrostatic loudspeakers, Quad, Martin Logain etc; the input transformers saturates quite quickly when subjected to DC so a protection circuit is highly recommended.

Who does not need them?

If your speakers are quite new and insurance will cover a loss; why bother? Also, if your system is in the normal or budget class.

If you are running power amps based on tubes and output transformers, any DC to the speakers are very unlikely (unless a shortage in the windings occur).

Special versions

For apmlifiers less than 30 Watts the LSP1w is ideal. Note that connecting this model to >30 Watts may destroy the unit! Same cost as the standard model.

Pricing, warranties

All prices in pairs. Freight not included. Prices are approximate, for detailed pricing, email me at:

k a j . l b @ i w a c . s e (remove spaces, spam-mail-robots are a pain!)

US: $170
UK: £100
EURO: 152
SEK: 1480

3 months of warranty if used properly. Warranty is limited to the product only. Supplier (IWAC AB) determines if warranty is valid or not. Suffice to say; if the returned unit was poorly put together or a component failed; it will be replaced with a repaired or a new one.

No liability to damage whatsoever: by purchasing this product you agree that IWAC AB cannot be held responsible in any way for any damage, either direct or indirect for using this product.

Availability

These units are hand made. I keep a small stock for immediate delivery of the LSP1 and LSP1w, but demand is varying. This means you could get a delivery from anywhere between days up to a month. At order I will return a good estimate.