Tweaking Sextets.

[bob orbell]

Completely agree Chris, especially power supply's, capacitors, well, get the power supply right first, it makes a world of difference. Bob

[Black Stuart]

Chris completely agree - **** in - **** out.

I still can't believe what I found inside the enclosures - quality control, inter stage inspection and of course final inspection, having worked for a couple of years in an engineering company - Gross Cash Registers this is mumbo jumbo for many British companies.

When I was moved up to final inspection I was greeted by a someone who told me " the only things you need here are a mallet and a screwdriver, if bashing it does'nt work, graunching it with a screwdriver will".

I had noticed that one speaker seemed more powerful than the other. When I opened up the enclosures the reason was obvious - there are two chambers inside the Sextets, one is for the Tonigen tweeter and the SEAS mid unit and the other for the SEAS bass.

For the upper chamber to work it needs to be sealed to achieve the sound pressure needed for those units to work properly.

So what did I find - work carried out by someone a few bricks short of a wall or a Friday afternoon job.

The Mk 1V units come with ribbon cable for the tweeter/mids. So, logically a slot needed to be made to take the ribbon cable into the bass chamber - what did I find?

4 x small shallow holes I suspect someone was trying to make a slot for the ribbon cables - they stopped - then a very large drill bit was used and again they were stopped and a smaller drill bit was used. The ribbon cable was then screwed up to be pushed through the cavity into the bass chamber.

Then one enclosure had a mountian of hot melt glue used to seal the chamber - and the other was'nt both were a total aberration in engineering terms.

I removed all the hot melt glue and used some plywood to seal both chambers from underneath and then used hot melt glue levelled off to fill the holes and used plywood to finally seal the upper chambers. At least now both chambers should yield the same SP output.

At the beginnning of this thread there should of course have been a total description of the internal construction of these speakers - hey but this is the UK.

The pipes used for the bass are very interesting indeed - why did no one mention this? They are made of a very dead/inert material and the upper 25% are 'bulbous' and are full of holes about the size of a pea - this is the only avenue for the bass notes to exit, I have never seen anything like it and I suspect they were specified by Peter Comeau. The last couple of inches of these pipes are lined with something resembling the 'hooked' part of velcro.

Due to the incredible heat here in the Tarn for a few weeks I did'nt work on the Sextets, now I am about to fit the new wiring and connect up to the external open ended sleeves of the new suspended x/overs.

I have decided to use the new external speaker wiring and the new (to me) Parasound Z3 amp. If all is well then I shall use the Hypex amp I bought from Dave Senior for the bass.

I could have saved quite a bit of money if I had thought about using the oxygen tubing instead of buying the 3.9mm FEP tubing. This is not being used as dialectric - the 4 x 0.5 mm copper conductors are inside the FEP oversized tubing which I do not twist and used to hold the 4 x together. This oxygen tubing is soft and pliable, excellent for the purpose - and it came for free.

I am using the 2mm solid core copper first for the bass but if I don't like it I shall use 6 x 0.5 mm. The way I have constructed the external x/over sleeves will make it easy to change wiring or components.

[Chris]

Are you using solid core copper without insulation and then inserting into tubing? I prefer multi strand wires, may be the skin effect with electrons migrating to the surface and stuff.
I have in my crossover teflon tubing then silicone tubing over the top, but that is using silver wire which does not suffer the effects so much of being oxidise by the air.

Chris.

[Black Stuart]

Chris,
The obsession with electrons is totally misplaced, they travel at a snail's pace unlike the actual signal. Take a look at Audiophilereview.com and the articles by Roger Skoff on cables, particularly the one - The Telephone is a Lie. This particular article shows conclusively that the whole audio industry refuses to see that the 'accepted wisdom' that has been used for decades is in fact total b/s.

Over 10 years ago now I tried using oversized PTFE and then FEP tubing and would never use anything else now. I repeat once again - the signal travels not only within the conductor/s but around it/them. This is established, proven scientific fact, since long before the 20th century, time for cable makers to ditch the b/s.

Yes I always use solid core conductors whether for low signal i/connects or high signal speaker wiring. Your point about electrons migrating to the surface even if true is irrelevant - it is'nt the electrons that carry the signal, see my comment in the first paragraph.

For my new speaker wiring I will first use 2 mm solid core copper inside 3.9 mm FEP tubing this then inside 5.5 mm hospital oxygen tubing. I shall also use 6 x 0.4 mm conductors, if multiple conductors dramatically enable more of the signal to pass through in i/connects I see no reason why this should'nt be the case with speaker cables.This s/hand tubing is excellent used this way as it is very pliable and will absorb any air borne vibration, It was only being in hospital after a cancer op.that I saw the opportunity that this material offered to those with an open mind.

I am going to contact the manufacturer to see exactly what fluorocarbon is used, what the melt point is and what adhesive is used to bond the different gauges together. This last point is important if longer speaker cables are required, the actual length is 203 cm.

[bob orbell]

Don't miss next months exiting post from Stuart on how to make the most of cable's. . Bob

[Greg.]

If I were an electron, being agitated in an alternating current in a cable between the ends of an amp and it’s speaker, I would love this thread for its entertainment value. Nothing like a good sci-fi tale. Having said that, science fiction and a writer’s imagination has often been the prompt for something real to start. Nevertheless, the thread to me reveals that it is no wonder we are living in a world that seems to be constantly influenced by conspiracy theories and fake news. So glad I don’t do Facebook.

[bob orbell]

You can rest assured Greg, that there will be more bits of pipe and copper to come, I am thinking of something like 20mm solid copper buss bars in 7/8" overflow pipe supported on PTFE standoffs. Bob

[A Stuart]

Tried that. Gave a curious liquidity to the sound. The music bubbled along nicely.
Alastair

[bikerhifinut]

if the electrons in a wire don't carry the signal, then what does? Given that his postulation that they don't travel all the way down a wire in an AC environment is a well known fact but doesn't detract from conventional electronic theory.
Has Stuart discovered a new branch of physics whereby electronics is merely a distraction to the true quantum magic?
The clues in the name.

A.

[Stanton]

Well I’m surprised, I had thought the signal was carried by the movement of electrons through the wire at the speed of light, and back again for AC. Thought that’s what I’d been told at college. But looking at Wikipedia it seems I am wrong and Black Stuart knows more than I first thought. See link below:

https://en.m.wikipedia.org/wiki/Speed_of_electricity