The QED SS50 5 way speaker switch allows you to connect and switch up to 5 pairs of speakers from one stereo amplifier. This new push button version of the popular Transmatch has a unique impedance matching design, that converts a net 2 Ohm load back to a safe 4 Ohm load to protect your amplifier. The QED SS50 product ensures that you are able to use up to five pairs of speakers in series from the same stereo amplifier to cater for your audio needs.
The terminals on the rear of the unit are marked ‘A’ and ‘B1’ – ‘B4’. The ‘A’ pair are switched directly for the highest quality, ‘B1’ – ‘B4’ are used for the remaining connections. Suitable for amplifiers up to 60 Watts RMS with a minimum impedance loading of 4 Ohms, although higher powered amplifiers can be used providing the safe operating limits of the Transmatch are not exceeded.
By using only the 4 ‘B’ outputs you can safely connect up to 4 pairs of 4 Ohm speakers
Suitable for use with the WM14 wall mounted volume control. Electronic overload protected. Silver plated switch contacts.
QED SWITCHING FAQ
What are the differences between Speaker Switches in terms of Impedance ?
All the speaker switches are configured so that if you use 8 Ohm speakers the minimum impedance seen by the amplifier will be 4 Ohms
What are the benefits of Series vs Parallel ?
The switches which have more than two sets of speakers use a combination of series and parallel switching to achieve the minimum impedance of 4 ohms no matter what combination of speakers are switched on. For the two way switches there is a choice between exclusively series or parallel versions. If you have 8 ohm speakers (and a 4 ohm min amp) you should always use the parallel switch. If you have 4 ohm speakers and a 4 ohm min amp you should always use the series switch.
All QED switches load on 4OHMS using 8OHMS speakers, what if you speakers are 6OHMS?
1. Check your amp – if it can cope with a 3 ohm load or less (and some can) then you are alright. The rule is you must always use speakers with double the impedance of the amp minimum. 2. If you only have two pairs of speakers then use the two way SERIES switch.
How do the switches deal with power, e.g. If I have an amplifier more than 150 watts?
These accessories use mains switches which are rated at 6A which means the max power they can handle is 288W given an 8 ohm load
If my amp is rated 6-16OHMS should I really be running a 4OHMS load?
NO, NEVER – you should use 12 ohm minimum speakers. You can get 16 ohm speakers though – but it may just be easier to change the amp.
Can I use them in reverse e.eg. As an amplifier switch.
NO – because the speaker switches are designed to have two sets or more of speakers attached to one amp, if used in reverse there is always the possibility of connecting two amps at once to one pair of speakers resulting in damage to one or both amps.
What is the technical definition of Transmatch
For the 5 way speaker switch we don’t use parallel or series switching but use transformer coupling instead. Again you have to use 8 ohm speakers minimum if your amp is a 4 ohm minimum amp. The impedance is then matched by the transformer (hence the name) so that a net 1.6 ohm load (all 5 sets of 8 ohm speakers switched on)is converted back to a 4 ohm load. One pair of speakers (A) is not connected to the transformer but is directly connected to the amp, these will be the main speakers. The four B pairs are connected via the transformer.