A7M/Scanspeak 26W/8534G 2-way

[Bill poster]

After a v long hiatus (family illness) I'm starting a relatively simple 2 way build using the A7M's

The grey cones look stunning, coating and colour is very subtle.



Hopefully the Scans arrive tomorrow. Plywood being cut and delivered for the weekend

will update as I go along.

 

[Bill poster]

10" Scanspeak vs 4" Alpair (altho the cone diameter is more like 2.5")

 

[chrisb]

It will be interesting to watch progress on this -have you discussed your plan for these yet?

 

[planet10]

Nit piks The 7 in Alpair 7.3 refers to a 7 cm (2.8") cone size. They are called grey but they are actually silver (1st gen had a grey cone and it is different)

An A7.x FAST can give fantastic performance, our A7.3eN + 2xSDX7eN perform really well.

The scan has a big peak at about 4kHz, even a fairly steep XO at a low frequency won't completely quell that, one might consider some measures to damp it down. The bass driver is sensitive enuff to give you a usually appropriate baffle-step compensation if you go with a passive XO.

What kind of box? What kind of XO?

dave

 

[zman01]

Interesting project Bill, look forward to more updates.

 

[BuildMeSomething]

Yes, an interesting project ... looking forward to the updates

 

[Bill poster]

Dave, Passive XO, box design is sealed bass (50 litres) and for the Alpairs something I havent tried before
Also trying out a little experiment (with help from the guys at Tech Talk), this might involve 3D printing.

 

[Bill poster]

Found out the wood yard have a router service- a few extra days wait before assembly

basic rendering

 

[planet10]

That is becoming an often choosen format

I have a new one in the initial stages, FF85wk with 2 SilverFlute W14 push-push in an ML-TL.

dave

 

[Bill poster]

Yes, it is. My second try at a side woofer build; I built one a few years ago (similar to a Boenicke design) but it didn't come out v well at all. Hopefully this one will be better.

One possible issue tho, a dip at 350-500hz on the Alpairs. What's causing that? Its right where I don't want it..

 

[chrisb]

Bill, we've found that side mounted woofers can work really well in opposing pairs - allowing surprisingly good results with smaller midbass drivers, such as the too cute for words Peerless 830870

 

[Moset]

This looks really interesting! I'd love to see how they turn out. I'm using CSS EL70s in MLTLs and they're really quite good but I'm craving louder and more bass. Have been looking at the Pensil 7 but am afraid that if I build yet another small single driver speaker, it'll be good overall but not really satisfying enough in the lower end.

How are they coming along?

 

[Bill poster]

Bit embarrassed to say they are still not assembled yet. I'll try to make some time next week, busy with house renovation. One tweak I'm debating is a circular baffle for the alpairs to match the baffle width of the woofers.


Sent from my iPhone using Tapatalk

 

[Moset]

No worries! I spent the better part of two years off and on renovating my apartment, so I know how time consuming that can be. Looking forward to hearing more!

 

[drtebi]

+1 on house renovation, I am in the fourth year Trying to do most of everything yourself takes a lot of time...

 

[Bill poster]

Ok house renovation done, decided to build another Alpair project first as I need to evaluate the tweeters. It's a 2 way quasi TL using the Alpair 12pw and Viawave tweets crossed at 3khz. Hopefully I've got my calculations correct with the X/O. First order on Alpair and 2nd on the ribbons.
Start building the cabs today and over wknd

 

[zman01]

Look forward to updates Bill.

 

[Bill poster]

Does this circuit look ok? Worried the resistors are in the wrong place. 1st order on Alpair and 2nd with l pad on tweets

 

[zman01]

Bill,

Maybe better to post on the FR section? Not sure how many folks are checking the MA forums nowadays.

 

[Bill poster]

True dat.
Almost completed one so maybe I'll try it first