Potential Bargain on Ebay

[ShinOBIWAN]

I'm not sure if the guy ships overseas but if your in the UK then you'll realise that £60 including delivery isn't much for a pair of speakers.

Then consider that you've got an d'appo design featuring 4" Aerogel mid/bass units (not sure on the model no. but looks to prestige series with the phase plug but with the basket design from the standard?). The tweeters are almost certainly TM025-F15.

I couldn't build and finish a pair for £60 so it makes sense to me. The crossover may well be suspect though, we'll see... if it is then a rework should prove fun.

Anyway, I've bought a pair for the shed so I can finally have some background music whist building stuff.

Here's the link:

http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWN%3AIT&rd=1

PS. Sorry but the auction ends in a few hours, I got in late myself and only just spotted them but thought it may benefit someone else looking for dirt cheap speakers using quality components. Maybe for the kitchen/shed/bedroom etc.

BTW I don't have affiliation with the chap selling them, just thought it was good enough value to tell others about.

EDIT:

Pics:

[ShinOBIWAN]

Al, if your out there, do you know what model no. those Audax 4" mid/bass are? Looks like these speakers were in production from 2001 to around 2004. Can't really find much more info about them other than they are manufactured and designed by Videologic of computer speaker fame.

The only thing I can identify is the TM025-F15 tweeter. It looks to have a Fs of ~1100hz and a highish Qts from the old spec sheet I've found.

Hmm... there's two things at odd's here; there's the MTM config which generally sounds better with lower XO point affording reduced off-axis lobing problems and generally improved power response. Although the center-to-center distance between the two mids looks to be around 17cm, which is pretty close in MTM terms.
And then there's the rather average tweeter that will very likely sound rough when crossed at 2khz, pretty efficient at a quoted 94dB thought. An educated guess would suggest the tweeter probably likes to be crossed at around 3Khz. Steeper slopes could help.

Has anyone worked with the Audax TM025-F15 tweeter?

Will be interesting to see what Videologic/Pure did with the XO.

[ocool_15]

"two custom made 4" Audax high definition aerogel drive units" so in theory you shouldn't be able to find them, depending how custom they are. An f3 of 55hz ported with 2 4" seems a bit optimistic.

[pinkmouse]

Well, without seeing the backs, it looks like they have the basket and cone of the AP100ZOs with the more conical rubber phase plug of the later HM100Z0s. It's not the HM cone as that is darker and much less shiny. They certainly look like a reasonable deal to me. If you're using them as upright MTMs rather than on their side as centre speakers, then my first thoughts for tweaking are to make them run as a 2 1/2 way, but of course that is always assuming there isn't more going on than we can see.

If you remember/go back to the Maplin/Audax buy out thread, I seem to remember suggesting a phase plug would be a nice improvement, it looks like someone else agreed!

[ShinOBIWAN]

ocool_15:

The Audax/Maplin buyout thread seems to suggest that the modelled response of a suitable ported enclosure would yield an F3 of around 55hz so this is feasible but with limited max SPL of around 90dB anechoic using 2 x AP100Z0's.
If these are AP100Z0's with phase plugs then the Qts of 0.65 suggests that best results aren't from porting but a sealed enclosure. Obviously this will result in an F3 of around 80hz but the groupdelay will be *much* better leading to a tighter sounding bass.

Al:

Thanks for the insights. I still don't have them with me yet and I'm just throwing idea's and what-ifs around. TBH I don't know if these are modded AP100Z0's and will have to measure them. I may just leave well alone if they sound OK but where's the fun in that?

There's some oldish Mission 70 series in the house that looks like they suspiciously use Audax units:



Looking at the textile dome and it bears a striking resemblance to the TM025 series. And the cone material on the 6.5 mid/bass looks to be the same as the Audax prestige aerogels, hell even the phase plug looks the same. I presume that these are Audax units? I picked these up a couple of years ago from Richersounds for £70 a pair, absolute bargain because they sound pretty superb for that money.

[lufbramatt]

yep lots of mission speakers from around that era used audax drive units, including the 78 series and 75 series. Although when i took the baffles off a pair of 780's the baskets of the woofers are made of plastic and appear to be integrated into the moulded removable baffle bit, so from that point of view they are custom units.

[ShinOBIWAN]

These things are tiny:



The Perceive's that you see in that shot aren't exactly large speakers. And these MTM's are even smaller than my ATC SCM7's and they're pretty small in the grand scheme. Any hopes of even half decent bass seem to be fast dissappearing.

Haven't had a chance to listen but the first impression are OK. Fit and finish is average but they're constructed out of 12mm MDF without bracing and despite being small, a knock on the side reveals that they ring badly compared to the Perceive's which are much larger speakers. So the build quality is a lacking.

I'll open them up after a listen.

[ShinOBIWAN]

Opened one of them up:



The 4" are marked AP100Z2 and the tweeter is marked TM020F3.

XO is 2-way, 2nd order with BSC. Component types look like the standard fare for a budget speaker and are of OK quality.

[Depth Charge]

How do they sound? Not much bass? Perhaps those drivers would be better suited as midrange drivers in a 3 way. How efficient are they?

If they're any good at that price I may just buy a pair for the mid drivers.

[ShinOBIWAN]

Originally posted by Depth Charge
How do they sound? Not much bass? Perhaps those drivers would be better suited as midrange drivers in a 3 way. How efficient are they?

If they're any good at that price I may just buy a pair for the mid drivers.

Still not listened to them yet. Have just finished setting them up though so will post something later.

I don't think its really worth buying them for the mids alone. When Audax used to supply drivers they did a version without the phase plug called the AP100Z0 and they sold for £15 each, and in the end, £5. The AP100Z2's are probably only worth a couple more quid and will sound very similar.

As a DIY'er I'd estimate the driver value at around £40 for all 6 then a tenner for MDF and £20 for the XO's. So all in your looking at £70 to build a pair. These cost £50 and come ready built so it makes sense to save a bit and cut out on labour.