Multi-Room Madness - Resistance is Futile!

mintyjim

Novice Member
Hi, I’m new to this forum but not to the world of mid-range hifi. I have a working understanding of how the various components interact, of amplifier and speaker resistance etc. I am, however, struggling to find a solution to my latest first-world problem:

I run a pair of Quad 12L speakers, (6ohms, 88db) which were perfect for bi-wiring from my old Onkyo network receiver.

I’ve now tipped the boat by flipping the Onkyo and (shortly) replacing it with a Quad Vena II Play streaming amp. The Vena is 6ohms so happy days. NO!

I’ve also got a pair of KEF Ventura 4 outdoor speakers (also 6ohms and 88dB) which I’d like to run off the Vena.

Ideally, I want to use a speaker switch, with an in-wall volume control for the KEFs. I’ve identified the QED SS20 (or SS21) parallel speaker switch and corresponding WM14 volume control. Easy. NO!

Connected in parallel, the Quads and KEFs show the amp 3ohms. While the QED switch claims to maintain a minimum 4ohm load to the amp, that spec is based on two pairs of 8ohm speakers. In any case, 4ohms is still to low for the 6ohm Vena II Play.

Does anyone have any suggestions for a protected speaker switch with a variable set resistance so I can show the amp 6ohms? Ideally, a switch which works with an in-line volume control for the outdoor speakers? I definitely don’t want to swap the speakers, but I would consider a different streaming network amplifier (rather than the Vena as long as it wasn’t too much more outlay).

I have looked but I’ve found nothing suitable. I’d be very grateful for any suggestions!
 

Mark.Yudkin

Distinguished Member
You need an impedance matching speaker selector, which cost a bit more. If you google on the term (or on the term autoformer) you'll find a bunch of options, such as from Russound, Sonance, Niles or Monoprice - all of which are of decent quality, plus a bunch of others from brands I don't know and hence can't judge.

The main issue you will face is that most of these devices are designed to control 4 or more pairs of speakers, which is reflected in the cost. There are models with volume controls, which allows you to have different speaker pairs at different levels, again adding to the cost, but if you already have a KEF in-wall volume control you won't need that feature.

In the end your specific choice will be dictated by your budget. For example the 2 channel Russound SDB-2.1 comes in at £275.
 

mintyjim

Novice Member
You need an impedance matching speaker selector, which cost a bit more. If you google on the term (or on the term autoformer) you'll find a bunch of options, such as from Russound, Sonance, Niles or Monoprice - all of which are of decent quality, plus a bunch of others from brands I don't know and hence can't judge.

The main issue you will face is that most of these devices are designed to control 4 or more pairs of speakers, which is reflected in the cost. There are models with volume controls, which allows you to have different speaker pairs at different levels, again adding to the cost, but if you already have a KEF in-wall volume control you won't need that feature.

In the end your specific choice will be dictated by your budget. For example the 2 channel Russound SDB-2.1 comes in at £275.
Thanks for the reply Mark!

I’m aware of the impedance matching option, I’ve actually already looked at Russound products. Unfortunately they’re “Designed for use with either 4- or 8-ohm speakers” (that’s taken from the description of the SDB-2.1).

If there was an audiophile two way switch with transformer protection and impedance matching suitable for 6 ohm speakers (or indeed, any combination of speaker impedance) then I wouldn’t mind spending a little extra. I can’t seem to find that though.

I think my only realistic choice is a series switch. With two pairs of 6 ohm speakers the amp would see 12 ohms (double the stated amp impedance level). I’d just have to suck up the loss in power/sound quality. Have you any experience of such a set-up and the resultant audio loss?

I’ve chatted with AudioFlow and they confirmed that their 2 way switch is in series; with one pair selected the amp would see 6 ohms and with both pairs, 12 ohms. It’s resistor protected so if both pairs are disconnected then the amp automatically gets a 200 ohm dummy load.

I’ve also been offered a used QED SS-22 series switch for less than £20. As it’s discontinued, I need to dig around to check what protection it offers.

I always seem to need the that one, specific, elusive piece of tech to make things work!
 

Mark.Yudkin

Distinguished Member
Although the Russound SDB-2.1 description says 4 or 8 Ohm, it will be fine with 6 Ohm speakers. The manual is clearer; see https://www.ceiling-speakershop.co.uk/pub/media/Productattachments//r/u/russound_sdb_manual_rev5.pdf.
The SDB speaker selectors work with all speakers rated from 4 to 8 ohms, and amplifiers rated for 4 to 8 ohm loads.
It remains my 2 speaker recommendation for your case, if you don't have an issue with the cost.

The QED SS22 is not autotransformer based and I would not recommend it. Of course, if your budget is limited to "less than £20" it may be the best compromise you can achieve, but that is a different question.
 
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