system polarity

[electric beach]

Has anyone taken the trouble to check the polarity of your system from start button to speakers? Anyone have an opinion on whether it actually matters?

I did experiment with a previous setup after seeing it suggested that a transformer winding would sound smoother connected one way than the other, but that the manufacturer connection could be arbitrary. I ended up with the CD player having a reversed mains lead.

The Bantam Monoblocks come with three power leads; one earthed and the other two are figure 8 L/N cables with an adaptor for the power supply connection. Unearthed is recommended, but then it strikes me that the live orientation would be completely random (so assume doesn't matter?) :confused:

I'm thinking of mains polarity with components here, but I have experienced a difference with speaker cables; with the Mini-T amp it sounded 'fuller' with cables reversed to the main speakers. My sub, which is fed from the same speaker terminals, seems considerably tighter when wired 'correctly' i.e. left to left, right to right but actually more bassy when reversed as compared to the main speakers - and they both come from the same amplifier posts :scratch:

I don't want to get anal about this but on the other hand, am I missing a basic set-up fundamental?

[Reid Malenfant]

With the figure of 8 mains cables it shouldn't make any difference which way round they are connected :)

The cables from your amps to your speakers depends in reality. What you need to find out is if any parts of your system reverse the phase. Some might & maybe the amplifiers do as some amps use shunt feedback & these will reverse the phase from absolute.

Assuming your system doesn't reverse the phase connect + to + & - to - on the speakers. Now most people cant hear the difference between absolute phase & reversed. The differences will possibly be noticeable in the bass & on something like a kickdrum. One way it might well thump you a tad & the other it might kind of suck :lol: What i mean is it might sound different.

Once you have established which way the speakers are to be connected the sub should be connected to give the greatest bass! You can then set the level, crossover frequency & phase control if you have one.

If you only have a switch that allows the phase to change from 0 to 180 degrees it doesn't matter how the sub is connected as you can simply flick the switch to see which gives most bass.

If you have a switch & variable phase control then set the variable to 0, select the switch for most bass & then gradually alter the variable phase to get the most bass. If you find any position from 0 decreases the bass then flick the switch & set the variable to 180 degrees & gradually lower it. Once the bass has peaked in volume you know that the sub & speakers are fully in phase & then you can adjust the crossover frequency & volume to fully integrate the system :)

Hope that makes sense :lolsign:

[DSJR]

Been there, done it loads of times and found that some systems are immune from a lot of this, whereas others make quite a difference if the fig-8 leads are the wrong way round or not.

As for absolute phase, some speakers are VERY sensitive to this, possibly because they have phasing issues of their own, but others are kinder to this artifact.

[Alex_UK]

As for absolute phase, some speakers are VERY sensitive to this, possibly because they have phasing issues of their own, but others are kinder to this artifact.

So, in simpleton terms for me, try swapping the red for the black on each speaker and see if it makes any difference? :)

[Reid Malenfant]

That's about it :eyebrows:

[Alex_UK]

Thanks Mark. :)

[Macca]

I tried reversing the phase at the speaker cables (amp out end) when I was using a Linn LK1 pre - the LK1 manual says you should do this. Sounded much worse straight away - I immediatley swapped back to normal.:scratch:

[Jac Hawk]

did any of you have that LP made by Decca I think, which you played obviously, while setting up your system, it tackled Phase, left and right channels etc. hhmmmmmm the old days:)

[Reid Malenfant]

I think i have that here, or at least some other test record :scratch: It also has a load of test tones, some just pure bass at different frequencies & one is a sweep from about 80Hz down to 16Hz if i remember right :eek:

Also test tones from 1KHz upwards to...

Might be the same thing or it might not :eyebrows:

[DSJR]

We're talking ABSOLUTE PHASE, not one speaker wired out of phase with the other ;)

The LK1 and 2 did indeed reverse phase from input to output and I found that doing as Linn suggested made the sound better. If you disliked the sound doing it this way, maybe you were alergic to the over-bland presentation :lolsign:

The Quad 33/303 BOTH reverse phase I understand, which isn't an issue when both are used together, but if like me you use them separately, this may need to be taken into account.

At the end of the day, if you don't notice a difference, don't worry and if you do, just use the way that seems best overall. if, on the other hand, you have a system "on the edge" where every bloody recording needs fine adjustments, then change your gear :D

[Jac Hawk]

I think i have that here, or at least some other test record :scratch: It also has a load of test tones, some just pure bass at different frequencies & one is a sweep from about 80Hz down to 16Hz if i remember right :eek:

Also test tones from 1KHz upwards to...

Might be the same thing or it might not :eyebrows:

this is the LP http://cgi.ebay.co.uk/UK-1967-DECCA-STEREO-CHECK-OUT-LP-SKL-4861-KERTESZ-EXC-/200615801084?pt=UK_Records&hash=item2eb5a230fc

[Reid Malenfant]

Looks different Mike, i seem to remember the label in the centre of the record is silver in colour. This just has a plain white (now more cream due to age) sleeve..

[electric beach]

Thanks Mark

I think... :scratch: