This could be exactly what you are looking for...:-)
tinyurl.com/38b3xy
One or two other manufacturers are, or are about to, produce similar products.
By the way home cinema surround sound is mainly used for DVDs and similar outputs rather than TV.
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What\'s for you won\'t pass you by
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I've got a set of Bose AM5's that are approaching ten years old. They still give excellent performance.
One of the key's to good performance of them is to get a minimal length of speaker cable between the power amp and the base box. I've got mine less than a foot long and it really does help.
I chose the AM5's for the power handling, I know they used to do a lower power model, but that wasn't capable of drowsing out my lawnmower when I was at the bottom of the garden!
Your best bet is to find a decent hi-fi shop where you can actually listen to several different set ups as we all have different ears.
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I read often, only post occasionally
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i had some bose 301's IV but sold them when i had the apartment. i was generally pleased with the sound. I had considered the Bose AM5 but reading reviews they tended to dislike the sub as its a passive unit and not active.
I do like bose products its just annoying that you cant get any discount and the prices tend to be set.
thanks
dave
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If you wish to spend your money on their products
at least look for a discount!
www.bose.co.uk/GB/en/about-bose/bose-stores-outlet...p
A triumph of marketing, and form over function.
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pmh (was peter)
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I recall a few years ago a friend in the trade telling me that a particular television set from this company was (allegedly) a rebadged Hitachi made in Turkey.
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What\'s for you won\'t pass you by
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Wandering round Tesco on Saturday I noticed TVs from two 'premium' brands were, on closer inspection, made in Turkey, presumably by Vestel.
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Short speaker leads
There is nothing technically or in properly conducted tests to support an argument that you need leads as short as one foot to improve speaker quality. A few feet of flat twin of reasonable cross section is OK, i.e. having a core that would otherwise be able to carry about 10-15 amps, is thick enough wire.
Nor is there any proof that you will improve sound quality by using 'oxygen free' speaker leads (ask the seller to tell you where the technical proof of this is -- he will not be able to). There is however both test and theory showing the problem that 'oxygen free' leads claim to cure, does not exist.
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Agree fully on the wiring side - the fancy cables have always been regarded by me as the Emperor's New Clothes.
However, using top quality Scart, HDMI and similar leads really does make a difference over the basic examples.
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What\'s for you won\'t pass you by
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If you are putting hi tech leads on, make sure that both cable runs are the same length - apparently it makes a difference.
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No, that is another myth.
The signal travels down the wire at a speed of about 186, 000 miles per second! (Just a bit less, if we want to be pedantic, due to the wire spacing and the nature of the cable insulation).
I will leave you to work out what the extra signal delay is from adding an extra 10 feet -- you arn't going to be able to hear it.
The audio signals, for all practical purposes, arrive at the speaker end of the wire, at same time as they are output by the amplifier. In fact the biggest delay, that can be an odd millisecond or so, is caused inside the speakers by things like the inductance-capacitance crossover networks. There you do have a design problem to address.
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>>No, that is another myth.
Indeed.
If you take an extreme signal at 20 kHz, and consider a 0.1 degree phase error, using C= f * lambda
3e8/(20000*3600)
ans =
4.1667
0.1 degrees of phase is equivalent to 4m difference in cable length.
On its own, this might make you think that it is important to get the cables exactly the right length.
But, when you look at the propagation of the sound through the air
340/(20000*3600)
ans =
4.7222e-006
You can recover this phase "error" by moving your head all of 4 microns to compensate. The natural movements of your body, even the elastic response to your heartbeat will leave this 4 microns figure in the noise.
At the low end of the frequency spectrum, you would need a cable length mismatch of about 4 km to get 0.1 degrees of phase error - even No_Fm2r doesn't have a house that big!
:-)
Number_Cruncher
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There's a good site here discussing some of the HiFi myths:-
sound.westhost.com/cables.htm
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Your reference is a very interesting one and starts off well. But, like most who challenge the audio fairy stories, I suspect he eventually succumbed to the opposition furor to the extent that he backs off a little with statements similar to 'there may be some who can hear a difference but they are the exceptions'.
For too many years UK hi fi magazines peddled tripe and built up such a great following that those who now oppose that religion get jumped on by large numbers who think the critic must be a nut.
The magazine writers became 'consultants' to (not for) amplifier manufacturers, because those (M's) could not afford their amplifiers getting rubbished in print and losing sales. Nor could they risk challenging rubbish articles, for the same reason.
But here is a hi fi site and a guy who spent £4000 on a pair of speaker cables and then did tests against some simple cable without hearing any difference.
Also read the inverted amplifier method of testing both amplifiers and wire for imperfections. Very clever, simple, and virtually can't be challenged. Far better detector than human ears.
www.avforums.com/forums/showthread.php?t=251658&hi...s
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You're wrong on the short speaker leads. Taken from one of the links posted elsewhere are a couple of examples of real difference, detailed halfway down the page in the link below.
sound.westhost.com/cables-p2.htm#spkr-leads
I'd copy the relevant section, under "Difficult loads" but I'd rather respect the author's copyright notice.
Once you've read the real scientific measurements that are detailed half way down the page you may find that cable inductance can, in some instances, where amplifier and speaker have some interesting impedances, make a real, scientifically measurable difference.
The author suggests several sensible ways of minimizing the inductance of the speaker cable. The way I gained some significant benefit was to move the power amp away from the rest of the stack to just behind the sub-woofer, which in the case of the Bose AM5's also contains the cross-overs. Thus, speaker length to the sub-woofer was reduced from 4m to about 20cm. This will reduce inductance by a factor directly proportional to the length change. Much easier than any of the methods that the author shows scientifically give measurable improvement. It also removes the capacitance increase that may possibly cause instability in the amplifiers using the methods suggested in the link.
I'm quite happy to debunk many of myths surrounding audio cables.
Oxygen free, directional and so many other phrases loved by the marketing people are all snake oil.
Whilst it probably wouldn't make a noticeable difference if the length I used went from 20cm to 1m, it certainly sounded so much better that the 4m length I had in the original set-up.
The other thing that really makes a difference is room layout and furniture. I've double blind tested with a few people just opening and closing curtains at one end of the room or the other. There's been good correlation that having curtains open at one end and not the other gives noticeably improved performance. It doesn't matter which end the curtains are open at, so long as one end is and the other isn't. That's a problem with having a hi-fi in a room that has patio doors in one end and a large window at the other, two larger reflecting surfaces allow standing waves to be set up.
There's a limit to what can be heard in the average house that's used for real living.
--
I read often, only post occasionally
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Speaker Leads
It is unlikely your leads reference brings up anything that was not covered very well in the amplifier designs of over 20 years ago, when I was active, and so I have not read it. But I know of exceptions.
The 'leads don't matter' exceptions area was one I avoided due to the amount of time it needs to explain it. I just covered leads with well designed amplifiers.
Here is an explanation, my last. Amplifiers use large amounts of negative feedback. At certain frequencies, and under certain load conditions, they risk that feedback will become positive, due to the phase shift caused by the load and by overdrive peaks. (An oscillator is often an amplifier with positive feedback -- it provides its own drive signal)
If it does, it will almost always occur at very high frequencies, usually well above audibility, and the output (as seen on a 'scope) can then display a range of effects, from occasional transient oscillations on the audio peaks, to full blown oscillation, and that in turn will affect amplifier bias points and that in turn cause distortion. Note, you will NOT hear this oscillation. Only the audio.
Having to drive inductive/capacitive cross-over networks, that are inside the speaker cabinets, is one of the most difficult design areas to cater for. Any well reputed manufacturer will know of this problem area and will have taken measures to minimise the risk, but there are rogue amplifiers that get through. The parts used for manufacture have spreads and transistors driven into overload (on peaks) exhibit difficult to predict behavior! And there will be a variety of speakers used with it.
One solution, used almost universally, is a small choke in series with the amplifier output followed by a resistor of about 10 ohms that is not effective until frequencies above audio where this oscillation is most likely to occur. At that frequency the resistor comes into play to control the phase and hold it in the stable region until the loop gain drops below unity.
If you have a rogue amplifier, that is prone to doing this, yes, altering the speaker leads can make a difference.
What you are actually doing, is altering what was happening at much higher frequencies than audio, that should never have be there in the first place, and stopping that has made the amplifier stable again. That in turn has improved the audio.
Many will use this to continue with their religion. Me? I bow out here.
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