Goodmans Magnum K Refurb and Modification (part 2)

[Daniel Quinn]

I will leave 2 out of 3 of your questions to the doc, but if it was me I would plug/play them to make sure they work and to get a handle on what they currently sound like .

[Dr Bunsen Honeydew]

Just play and listen, they won't be right but you get a handle on them. Wires fine, bit scruffy but it matters not. I am not doing the job I cannot hold your hand just do it and learn. There is loads of inf in back posts on lots of threads so why do I have to repeat it.

[Ronin]

Thanks guys.

I will hook them up and report back.

Ronin

[istari_knight]

Ronin, capacitors look fine, as does the wiring. All + cables to to + connections on the drivers & likewise for the -'s... 1st order (single component in series, as you have done) has 90 degree phase shift whereas 2nd order (as was originally fitted) has a 180 degree shift necessitating the tweeters wires be reversed.

Give them a go now, I would expect them to sound very lively and probably quite bright but at least it will give you some idea of what you've got to work with. Using the Doc's method you apply a layer of Bison over the dust caps & a worm of Bison around the dustcaps. Here is a picture showing one of Alfi's AP2 drivers:



Once that's dried you can add a coat of Plastidip over the entire cone surface. Try to listen to a familiar track after each application (preferably the same track each time!) The first thing you're trying to achieve is good integration between the bass and mid drivers, once they sound right to you its time to find the right tweeter balance playing with padding resistors... Of course the tweeters may be fine as they are, I don't know their sensitivity rating or the originals ? Most paper cone tweeters are fairly efficient so if the new one's are less efficient that will work in your favour.

[Dr Bunsen Honeydew]

It looks like everyone is skimping on the doping I use far more around and over the dustcap, but try yourself and see.

http://www.cyanotec.com/bison/ I recommend a small tin for value http://www.bison.net/en/products/642-co ... bison-kit/ and just keep the driver flat on its back and pour evenly onto dust cap, gravity will do the rest.

[istari_knight]

Agreed, I would definitely add more than shown in the above picture - It was just an example to give Ronin an idea of where to start

[Alfi]

Just like to add this guy's..

That photograph is showing the first worm of Bison I applied, since then I've applied a whole lot more! I've used Blu tac too because I couldn't wait for that amount of glue to dry!

Doc's pics of his kevlar drivers really woke me up to the fact I should be looking to add more glue. It makes a big difference - oh yes- it certainly does!

Alfi.

[Ronin]

Ronin, capacitors look fine, as does the wiring. All + cables to to + connections on the drivers & likewise for the -'s... 1st order (single component in series, as you have done) has 90 degree phase shift whereas 2nd order (as was originally fitted) has a 180 degree shift necessitating the tweeters wires be reversed.

Thank you,I'm a little confused about the "phase shift" thing.should I have done something differently

Using the Doc's method you apply a layer of Bison over the dust caps & a worm of Bison around the dustcaps. Here is a picture showing one of Alfi's AP2 drivers:

Thank you so much for this info istari ,I've spent ages trawling through this forum looking for it and the picture is a big help

Once that's dried you can add a coat of Plastidip over the entire cone surface. Try to listen to a familiar track after each application (preferably the same track each time!) The first thing you're trying to achieve is good integration between the bass and mid drivers, once they sound right to you its time to find the right tweeter balance playing with padding resistors... Of course the tweeters may be fine as they are, I don't know their sensitivity rating or the originals ? Most paper cone tweeters are fairly efficient so if the new one's are less efficient that will work in your favour.

I'll follow your advice thanks.Here's the specifications on the new tweeter http://www.madisound.com/loudspeaker_sp ... %2032s.pdf

Give them a go now, I would expect them to sound very lively and probably quite bright but at least it will give you some idea of what you've got to work with

Switched the amplifier on and only one speaker was working and the other had a loud fluttering sound (like strong wind through a ships sail) .Turned it off straight away and checked all my work,everything looks ok not sure whats happened I've got a multimeter,but I'm not sure what I can check with it that would help apart from continuity .Any advice would be most welcome

Thanks for the links Doc and your opinion on extra doping.

And thanks Alfi for you input.

Ronin

[Dr Bunsen Honeydew]

The amplifier is going unstable (motorboating) on that channel, you have done something wrong. Compare what you did between the two speakers one is fine the other is not. The other possibility is that the amp has developed a fault, but an amp doesn't suddenly go unstable, something is driving it to do it.

This really is becoming a high work load with questions you can work out for yourself. Relax use logic sit and compare and follow what we have said. Use the archive, it is all in there. It is called DIY (do it yourself) for a reason.

[istari_knight]

Motorboating as Doc says... What amp are you using Ronin ?