Sub down - rescue mission initiated
 

OK, the sub's down - it's resting on a crumbling ledge and the least noise
or vibration will send it sliding into the icy, black, bottomless, crushing
depths below. To make matters worse, the cook has just used up a sack of
Brussels Sprouts which were a tad past their Sell By and now the crew have
all got chronic wind. The situation's desperate - it's only a matter of
time...

Woah! Woah! Woah!

Scrub all that - wrong text! (That's my new movie plotline!! :-)


OK, the replacement sub from Proelektra.de turned up today and releases the
damaged one

http://www.apah69.dsl.pipex.com/keit...ustedsub02.JPG

for a spot of fettling....

As an HT sub, even the damaged one has been quite good just taped up, but a
quick try on my audio kit shows it up to be a hooty thing that, quite
frankly, isn't as good as my speakers on their own! It sounds a lot better
with me sitting on it, so I'm hopeful I can turn it into summat useful for
not much wedge.

I want the sub for 'Headphones' (ask Fleetie) but I'm taking the line that
if it ends up no worse then the original it will be good for another HT sub
if nothing else. I mentioned a while back that I wanted to get the LF off my
fronts. That's been achieved now and (I think) I perceive a cleaner sound
all round - plenty good enough for our requirements anyway.

I haven't dismantled it yet so I don't know what the driver is - chances are
it'll be a bit 'oriental' and a totally unknown quantity in any case. I'm
wishin' and hopin' that transferring the gubbins into a much stouter cabinet
will result in a better sub.

A few questions then:

19mm MDF for the cabinet - any problem with that??

Crossbracing - good idea or don't bother? (It's got none atm, as far as I
can see....)

This one's ported - does the new cabinet have to be?

If not ported, what then?

Glenn B mentioned TS parameters - important or would just copying the
internal dimensions do?

I would appreciate any thoughts or ideas.

TIA

Sub down - rescue mission initiated
 

Keith G wrote:

A few questions then:

19mm MDF for the cabinet - any problem with that??

Crossbracing - good idea or don't bother? (It's got none atm, as far as I
can see....)



see posts 4 and 7 on this thread for ideas on cross bracing.

apologies for the very long link

http://groups.google.com/groups?hl=e...%2 5404ax.com

Sub down - rescue mission initiated
 

"Tat Chan" wrote in message
...
Keith G wrote:

A few questions then:

19mm MDF for the cabinet - any problem with that??

Crossbracing - good idea or don't bother? (It's got none atm, as far as I
can see....)



see posts 4 and 7 on this thread for ideas on cross bracing.

apologies for the very long link


Thanks for that - very useful. I'm thinking to construct an entirely new
cabinet (research being carried out to see if we can work 19mm particle
board) and I will now definitely crossbrace the cabinet.

I've taken a few more hasty snaps if anyone is interested*:

http://www.apah69.dsl.pipex.com/keit...ustedsub06.JPG

http://www.apah69.dsl.pipex.com/keit...ustedsub07.JPG

http://www.apah69.dsl.pipex.com/keit...ustedsub08.JPG

http://www.apah69.dsl.pipex.com/keit...ustedsub09.JPG

http://www.apah69.dsl.pipex.com/keit...ustedsub10.JPG

http://www.apah69.dsl.pipex.com/keit...ustedsub11.JPG

http://www.apah69.dsl.pipex.com/keit...ustedsub12.JPG


It can easily be seen that the box is constructed from little better than
cardboard, the driver is a bit 'anonymous' to say the least and the amp is
quite surprisingly good by comparison. There's a bit of a prob to be sorted
in the amp - works fine on Line In (ie AV amp feed) but is a bit 'silent' in
one channel using the 'Hi Level' (speaker wires) Ins and Outs. Nothing too
obvious, but I haven't had a good scrute yet.

I'll probably post a webpage on my site when I'm done in case it's of any
use or interest.

*Having said that - does anyone here think this 'Show N Tell' malarkey is of
any interest at all or am I just wasting my time?

Me? - I love pix of anybody's kit and/or their doings and would like to see
more of them. (Eternal yap about 'flat responses' do get a bit wearying
after a while, I find....)

Sub down - rescue mission initiated
 

Keith G wrote:

*Having said that - does anyone here think this 'Show N Tell'
malarkey is of any interest at all or am I just wasting my time?

I'm most definitely into it.


Me? - I love pix of anybody's kit and/or their doings and would like
to see more of them.

I've cleared away the arty stuff from the studio and will be using the space
for some leccytronics. I've hijacked the studio webcam and will be using it
as a benchcam - it's taped to an anglepoise lamp. I'll see if I can get
round to adding a webcam page to my wee site about the speaker rebuild
fantasy. Meantime, find the webcam page on my arty site if you want to take
a look (it's currently showing a bit of paper lit by IR emitters in a dark
room - the webcam's IR filter has been removed).

Tonight's fun ******** is to see how many voltage regulators I can fry...


--
Wally
www.artbywally.com
www.wally.myby.co.uk

Sub down - rescue mission initiated
 

"Wally" wrote in message
...
Keith G wrote:

*Having said that - does anyone here think this 'Show N Tell'
malarkey is of any interest at all or am I just wasting my time?

I'm most definitely into it.


Me? - I love pix of anybody's kit and/or their doings and would like
to see more of them.

I've cleared away the arty stuff from the studio and will be using the
space
for some leccytronics. I've hijacked the studio webcam and will be using
it
as a benchcam - it's taped to an anglepoise lamp. I'll see if I can get
round to adding a webcam page to my wee site about the speaker rebuild
fantasy. Meantime, find the webcam page on my arty site if you want to
take
a look (it's currently showing a bit of paper lit by IR emitters in a dark
room - the webcam's IR filter has been removed).


OK, Wally - links to pix then!!


Tonight's fun ******** is to see how many voltage regulators I can fry...


And I'm going to have a poke about in the plate amp to see if I can see why
one channel is dead on the 'Hi Level' connections:

http://www.apah69.dsl.pipex.com/keit...ustedsub10.JPG



Wally
www.artbywally.com
www.wally.myby.co.uk


Nice sites, but you definitely got shafted on the walling stones (under the
speakers).....

;-)

Sub down - rescue mission initiated
 

Keith G wrote:

OK, Wally - links to pix then!!

What, pics of the webcam?


And I'm going to have a poke about in the plate amp to see if I can
see why one channel is dead on the 'Hi Level' connections:

You'll be wanting your scope out, then...


Nice sites, but you definitely got shafted on the walling stones
(under the speakers).....

You're right - Homebase ain't the cheapest. ;-)


--
Wally
www.artbywally.com
www.wally.myby.co.uk

Sub down - rescue mission initiated
 

"Wally" wrote in message
...
Keith G wrote:

OK, Wally - links to pix then!!

What, pics of the webcam?


And I'm going to have a poke about in the plate amp to see if I can
see why one channel is dead on the 'Hi Level' connections:

You'll be wanting your scope out, then...



I've had a poke about wiv me meter and it all looks OK, but summat's not
right - when the sound is routed out to the speakers one of them's severely
attenuated (barely audible) while the sub works fine. I've tried to find a
short but no luck so far.

The speaker connectors are on the board above the surprisingly large
trannie:

http://www.apah69.dsl.pipex.com/keit...ustedsub10.JPG


The amp side (fed from a Line In) is fine and it looks like the speakers are
a simple 'pass through' (??). I've put it back on the AV setup and it's
working very well (for a tenner.....!!! ;-) - any ideas? (I know bugger-all
about electronics and bugger-all² about SS circuitry!!)

Trying the other (perfect) sub on the audio has brought some startling
results. I might be about to change my mind about subs on audio and might
have to consider summat a bit more 'musical'....???

(Or swap the plate amps over leaving the dodgy amp in the OK cabinet for AV
use and putting the OK amp in a better box....)