Bi-Wirable Speaker Question

choons

Hello,

I have a question on Bi-Wirable speakers when connected to a single output amp. Parallel to high/low seems to be most common way of wiring. The speakers are 8 & 6 ohms but the amp is rated 8-16 ohms so I am reluctant to use them in parallel.

If I connect the speakers with the high/low in series, will I lose the high and low frequency due to crossovers in the speakers?

Can't seem to find an answer online!
Thanks

ZENER

The rating on the speaker is the impedance and is an indication of the speakers opposition to AC current at 1KHz. The figure is nominal and differs at different frequencies.

Bi-Wirable speakers will have 2 sets of posts on the input which are normally bridged RED to RED and BLACK to BLACK thus allowing one pair of wires to supply both the low frequency and high frequency drivers simultaneously or, by removing the bridges, to supply each section separately. The two pairs of wires are then connected to the same pair of posts on the amplifier - Bi-Wired, or to two different amplifiers - Bi-Amped.

The belief (I'm a sceptic) for Bi-Wiring is that the cable feeding the High Frequencies will not be "poisoned" by the low frequency current normally fed to that section of the speaker thus improving the sound quality (supposedly) obviously the cable feeding the Low Frequencies won't be effected by the Highs either.

Bi-Amping is the real way to go but is a lot trickier to set up. With Bi-Amping the cross-overs are removed from the speakers and Hi-Pass and Low-Pass filters are used on the inputs of two separate amplifiers to separate high frequencies and low frequencies actively and only amplify those signals with a particular amplifier before feeding out through different cables to the respective speakers.

So if you have a set of speakers which have the required 4 posts on the rear and you have removed the bridge pieces then running 2 cables back to a single pair of posts on the amplifier then you are not presenting a different load to the amplifier. The Low frequency section of the speaker will present it's loading impedance only at low frequencies while the high frequency section (tweeter) will present its loading only at high frequencies. The resultant loading is the total printed on the sticker or plate on the rear of the speaker housing.

As to connecting in Series or Parallel, generally commercially made speakers will have some form of crossover built in, the post presented on the connection plate allow you to connect to each section of the crossover. Wiring these to connect the 2 sections in a series load won't work. They are designed to be connected in parallel.

I hope this hasn't caused even more confusion. Where are you reading the 8 and 6 ohm figures from ?

Ken

choons

Ken, great description and all makes sense, thanks for that. 8 and 6 ohms are written on the back of the speakers next to the terminals.

I've done some testing and more googling. Series connection does indeed not work - I guess the high and low frequencies are being removed by the crossovers so you end up with a narrow middle range.

I'll run them in parallel which results in 3.43 ohms - not enough for the 8ohm amp unfortunately. This is a spare system so happy enough to just see how long the amp lasts :pac:

Amp Denon UDRA-M7
Speakers Technics SB-CH7

ZENER

Don't confuse resistance with impedance. You don't say what speakers you have bit I'd guess they have an indicated impedance for each range, HF and LF. The amplifier won't see it as 3.4 ohms, it will see different impedance at each part of the range.

If you give the make/model of the speakers we could give better advice but unless you're driving the amp and speakers flat out I wouldn't worry too much.

Ken

Didn't see that you'd provided details, sorry.

choons

ZENER wrote: »

Don't confuse resistance with impedance. You don't say what speakers you have bit I'd guess they have an indicated impedance for each range, HF and LF. The amplifier won't see it as 3.4 ohms, it will see different impedance at each part of the range.

If you give the make/model of the speakers we could give better advice but unless you're driving the amp and speakers flat out I wouldn't worry too much.

Ken

Didn't see that you'd provided details, sorry.

Also sort of makes sense, thanks again