View Single Post
  #16   Report Post  
Posted to rec.audio.high-end
[email protected] skybuck2000@hotmail.com is offline
external usenet poster
 
Posts: 50
Default Powering Cambridge 210w 8ohm Sub woofers

On Thursday, July 27, 2017 at 10:01:55 PM UTC+2, Peter Wieck wrote:
NONONONONONONO
=20
Did I mention NO?=20
=20
You are making this WAYYYyyyy too complicated, and why I asked the questi=

on in the first place, and why I mentioned KISS earlier, AKA, K-eep I-t S-i=
mple S-tupid.=20
=20
Please go back and look over what has been posted to-date:
=20
a) This speaker is designed to accept *UP TO THREE* separate outputs in t=

he same speaker.=20
b) Those outputs, typically are Channels A, B, & Center. Or, Right, Left =

& Center.=20
c) You *DO NOT* have to drive all three voice-coils.=20
d) You should *NOT* run the voice-coils in Series or Parallel. =20
e) You may need some sort of crossover system from your A & B & C outputs=

I do not know what sort of speakers you have, or their impedance. Hence th=
e term "May".=20
f) It !! DOES NOT !! require 70 watts to drive it. That rating is for the=

maximum average power over a specified range of frequencies over a specifi=
ed time. Were you to run 70 watts into that device continuously, it would b=
urn up. Don't understand? How long can you hold onto a (lit) 60-watt incand=
escent light bulb without damage? That speaker will make plenty of noise on=
as little as 2 or 3 watts.=20
=20
Essentially, you have a sub-woofer designed to accept input from Channels=

A, B, & Center from the receiver detailed below.=20
=20
https://www.amazon.com/Denon-7-1-Cha...ued-Manufactu=

rer/dp/B001BKND5W
=20
You need to find a way to provide mid & tweet to your main speakers for c=

hannels A, B & Center. That is your ONLY task here. This may involve some s=
ort of crossover, or some sort of careful wiring of your existing speakers.=
Please note the impedance range on the Denon, and do not go outside those =
nominal ratings.=20
=20
It seems to me that you are expending a great deal of effort to use a mar=

ginal far device outside of its design parameters.=20
=20
Peter Wieck
Melrose Park, PA


I think you miss understand.

I want to accomplish the following for a full pictu

I want the denon receiver to power 7 satelite speakers which it is doing fi=
ne as I write this.

But I also want *something* to power the subwoofer.

Now if I was a millionare I could:


1. Buy 1 receiver + 1 subwoofer per channel + 1 speaker per channel.

For a total ammount of 7 speakers + 7 subwoofers + 7 receiver.

Every receiver would then be in control of 1 speaker + 1 subwoofer.

The receiver would split the signal of the channel in two signals 1 for the=
speaker 1 for the subwoofer.

2. There would be an 8th subwoofer and 8th receiver to simply process the L=
FE signal.

So in total there would be 7 speakers 8 receivers 8 subwoofers.

However a cheaper solution costing less space would be:

3 receivers + 7 satelites + 3 subwoofers.


Receiver 1 processes left/center/right and splits this off to 3 speakers an=
d 1 subwoofer.

Receiver 2 processes side left/side right and splits this off to 2 speakers=
and 1 subwoofer.

Receiver 3 processes rear rear/ rear left and LFE and splits this of to 2 a=
nd 1 subwoofer.

So then I would some something like "surround bass".

However I suspect the Gigaworks S750 is already doing this.

It's electronics seperate the signals as above but instead of three receive=
s and 3 subwoofers it's simply 1 subwoofer with three voice coils for more =
fine grained bass/more control over bass.

So at least we agree on something: the tripple voice coil subwoofer is acce=
pting 3 inputs.

However those 3 inputs could be a mixed signal as described above as sinus/=
cosinus signals should mix quite easy.

What the Gigaworks is actually doing will remain a mystery for now.

One possible way to reverse engineering it is to place a monitor/volt meter=
or something on each coil, one at a time and play the same audio file and =
see what happens.

Also disconnecting some plugs/signals could shed further light on this.

This subwoofer is part of a 7.1 surround sound set.... so sending only left=
/center/right to it makes no sense what's so ever.

Why not send all 8 signals to it by mixing them down to 3 first ?

Also the subwoofer is rated at 210 RMS.

So how can you say it's only 3 watts ? Sounds weird to me.

This subwoofer is according to repair man and pictures and guys on forum po=
wered by 3 amplifiers each of 70 watts so you were dead wrong there or some=
thing is amiss

Also pretty much all speaker outputs are already used from the denon receiv=
er.

You did give me an idea though.

I could re-write some off the speaker outputs directly into the subwoofer, =
perhaps even the three seperate coils.

Then I would indeed how to get rid of cross over frequencies and make sure =
all signals are passed raw/unmodified or reverse it and send low frequencie=
s... not sure if denon can do this... but it's beside the point since denon=
in normal operation mode only has 1 subwoofer output.

So this *main stream* device can simply NOT do with the Gigaworks might be =
doing.

Which could mean the Gigaworks is a revolutionary home theater system which=
could explain why a Saboteur sabotaged the production facility to use "con=
ductive glue" Which would only reveal it self after Q&A already passe=
d the devices.

The Q&A did not test the devices properly to simulate prolonged use of heat=
..

Bye,
Skybuck.