HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

Take this....



and this steel angle



8mm by 73mm........oooo feel the girth



To produce this.....



When de-rusted and hammerite black painted on should be ok. Just need to fill in the sides and back panel and jobs a good un. Weighs a ton already just with those 4 angle sections in.

Cut the angle 8mm steel for the other speaker today and removed the rust. No pics today.

Looking online regarding steel lined speaker cabs i found this (just inquisitive)

Acoustic Energy AE1

Uses 5mm steel plates inside, front baffle is MDF + 10mm Aluminum, speaker cone is metal (Aluminum ?) like the MS902S but not continuous profile.

AE1 has a crossover , a bloody port and is £2000

Probably stuffed full of god knows what as well.

Anyway hifichoice seem to see the benefits of a rigid, high mass enclosure

So that's about £200 worth of components, at best. The bass/mid is likely to have some breakup hence the third order (!) crossover at 3khz.

From a stereophile review:

"The crossover, which is mounted on the rear of the recessed terminal panel—good-quality five-way binding posts are fitted—acts at 3kHz and consists of a third-order Butterworth, 18dB/octave high-pass leg and a 24dB/octave low-pass leg with a phase-compensating network. The low-pass section uses iron-dust-cored inductors, the high-pass air-cored coils. Both use low-loss polyester capacitors. (I must admit that I raised an eyebrow at this, polyesters, in my opinion, not being as sonically neutral as, say, polypropylenes.)"

For low-loss polyester, read low cost.

Hi Simon,

I had not looked at any more reviews of the AE1 so thanks for the info. It is a bit off topic but the steel lining is what got me interested.

Since joining this forum i am becoming more and more able to spot & translate marketing like the capacitor one you spotted. Anyway Simon, you seem to know a fair bit about speakers. Glad to have you around.


Found an article on a Leema acoustics speaker - 1.2mm steel cab with bitumen damping. Designed on the bbc principles. Oh dear

http://theaudiophileman.com/lemmas-xen- ... art-leema/

karatestu wrote: ↑Wed Aug 09, 2017 6:22 pm Cut the angle 8mm steel for the other speaker today and removed the rust. No pics today.

Looking online regarding steel lined speaker cabs i found this (just inquisitive)

Acoustic Energy AE1

Uses 5mm steel plates inside, front baffle is MDF + 10mm Aluminum, speaker cone is metal (Aluminum ?) like the MS902S but not continuous profile.

AE1 has a crossover , a bloody port and is £2000

Probably stuffed full of god knows what as well.

Anyway hifichoice seem to see the benefits of a rigid, high mass enclosure

The AE1 never sounded that great usually paired with Audiolab so I hope you get better results. Anyway less than the £800 or so they cost back in the 80's.

Thanks for the kind words Karatestu. I'd never claim to know as much as some others on the forum but i do try to keep an open mind and question 'conventional 'wisdom'. As George Bernard Shaw said, "The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man."

The original AE1 had metal cone drivers, which in their case meant a tin-can take-off in the mid hf (8khz). All the crossovers in the world can't mask it completely and it's been found that just acoustic coupling at this frequency by the tweeter can have audible effects as the cone rings in sympathy. We used them with Naim and they didn't sound so bad I remember. I wonder what doping could do to this kind of cone?

_D_S_J_R_ wrote: ↑Thu Aug 10, 2017 10:37 am The original AE1 had metal cone drivers, which in their case meant a tin-can take-off in the mid hf (8khz). All the crossovers in the world can't mask it completely and it's been found that just acoustic coupling at this frequency by the tweeter can have audible effects as the cone rings in sympathy. We used them with Naim and they didn't sound so bad I remember. I wonder what doping could do to this kind of cone?

The MS902S I am doc modding have continuous profile aluminium cones for mid/bass. I have already doped them so I will be able to answer your question fairly soon I hope. With there being no dust cap in the centre the bison kit just settled in the bottom of the cone. May need more, won't know until I listen to them. Oh and I will see what a coat of plastidip brings to the party too

Regarding metal dome tweeters - every pair of speakers I have (3) uses them except my doc mod Marantz imperial 7 (not finished yet ) which I have I visaton G25 for . I am going to have a go at doping the rear of the metal dome tweeter on these MS902S with plastidip and see what happens. May do it to others as well if results are favourable