Going active ... ?

[hoopsontoast]

Fostex FF225K (8") and Veravox 5S (5")

Cheap low quality driver with a pressed steel basket.

ATC 5"

That's more like it. That looks like a good quality piece of kit.

I have a small pen1s

:hand: Whoh there boy. That's not the sort of thing you should be admitting on a public forum. Especially to a bunch of immature audiophiles. We'll be misquoting that post for months now.

Steve, you seem to be baising a drivers potential performance on its subjective aesthetic rather than any actual parameter.

In what way does a cast frame have any bearing on a drivers performance in a domestic setting, other than looking nice?

The Fostex driver is a very highly regarded full-range driver, and a very high magnet strength and low cone mass.

You point out that the ATC driver looks nice, although it probably has the joint worst set of compromises in its design.

I was commenting that you seem to think the AVI sub driver is particularly special, it isnt. Its an OEM basket with a custom magnet and cone, now most subwoofer drivers optomised for lots of equalisation and a small cabinet are likely to have a driver that looks similar with similar parameters to have one goal, to get the deepest bass from a sub-optimal cabinet.

I also ment OEM as in that its direct to the manufacturer, not for public sale, so I would not expect it to be able to be bought, although you could probably buy something similar, have a look at car audio sites.

The basket is the same, its used by a lot of people, eminence as mentioned for one, who I am guessing as they use the same cast frames as a lot of other manufacturers, and being the biggest they probably would supply them.

 

[lindsayt]

Perhaps I should have included the fact that divorce was not an option.

Be thankful he didn't recommend these...

(Lindsayt's Bozak B-4000s dwarfing some compact stand-mount speakers.)

However, it is worth noting that Lindsayt has the good fortune to be able to spread all this kit out in his Victorian mansion ...

Living in a Victorian mansion helps in blending-in large vintage hi-fi kit and giving the wife a choice of rooms in which to entertain visitors.

... so always take his advice with this in mind.

Basically, get a mansion.

Thank-you for your contribution Chebby.

 

[steve_1979]

:Steve, you seem to be baising a drivers potential performance on its subjective aesthetic rather than any actual parameter.

In what way does a cast frame have any bearing on a drivers performance in a domestic setting, other than looking nice?

Do you really think a cheap pressed steel spider is as good as a solid cast one? A cast spider is much more rigid.

I was commenting that you seem to think the AVI sub driver is particularly special, it isnt. Its an OEM basket with a custom magnet and cone, now most subwoofer drivers optomised for lots of equalisation and a small cabinet are likely to have a driver that looks similar with similar parameters to have one goal, to get the deepest bass from a sub-optimal cabinet.

I also ment OEM as in that its direct to the manufacturer, not for public sale, so I would not expect it to be able to be bought, although you could probably buy something similar, have a look at car audio sites.

The quality of many of the more expensive car audio drivers is exellent - good enough to put many hifi speaker drivers to shame. There are of course plenty of cheap boomers like you get in chavy Citroen Saxo's too.

The basket is the same, its used by a lot of people, eminence as mentioned for one, who I am guessing as they use the same cast frames as a lot of other manufacturers, and being the biggest they probably would supply them.

I honestly don't know if Sinar Baja use the same basket or just one that looks similar on some of their other speakers. I suspect that you don't know either.

 

[hoopsontoast]

I hate to nit pick but its a cast or stamped frame, the spider is part of the suspension assembly.

I do honesly think a stamped frame is as rigid as a cast one in a domestic enviroment.

Again, as mentioned the only advantages I can think of if you have a PA speaker that might be knocked about a LOT and subject to a LOT of abuse then maybe a cast frame might help with durability, even then I think its marginal given the move towards lightweight Neodymium magnets. The other is heat transfer, again only applicable to PA speakers where constant sustained high volumes are used, and the cast frame can have some heatsinking built in, much like these:

External Heat sink like the Volt Radial drivers:

Internal Heatsinking like this Eminence for example: (a more common design)

I would probably bet good money that the cast frame is the same on the AVI sub as used by a lot of other people, its not a disadvantage, means that the manufacturer has spent more of the design/research on the motor design, voice coil, cone, suspension etc rather than developing a costly frame.

 

[steve_1979]

I hate to nit pick but its a cast or stamped frame, the spider is part of the suspension assembly.

My bad. I ment to use the word 'basket' not spider (posting in a rush while getting ready for work).

 

[hoopsontoast]

The EV Sentry III bass driver has enough linear travel to play at 116 dbs at 40 hz without getting near hitting the limits of the cone suspension. They do not have rubber surrounds. They have foam surrounds. The magnet is not small for a 15" driver. You'd need to put them next to other 15" drivers to see that. Apart from that, everything in your post was correct.

This is what an AVI bass driver looks like.

The pictures speak for themselves really.

AVI 12" Sub Version: (I cant find a pic side on of the 10" one showing the vented area for the Spider)

Eminence LAB 12 Subwoofer Driver:

Quick 2min google for "10" Subwoofer" resulted in 3 different drivers with the same frame.....

 

[Andy-F73]

I love it how DIY’ers come on forums like this and think they no better than the respective manufacturer. A manufacturer will spend thousands researching and testing a product only for a DIY’er to come along with a handful of watts and a driver that was optimised back in 1973 and think they know better.

Potty the lot of them …

 

[chebby]

Perhaps I should have included the fact that divorce was not an option.

Be thankful he didn't recommend these...

(Lindsayt's Bozak B-4000s dwarfing some compact stand-mount speakers.)

However, it is worth noting that Lindsayt has the good fortune to be able to spread all this kit out in his Victorian mansion ...

Living in a Victorian mansion helps in blending-in large vintage hi-fi kit and giving the wife a choice of rooms in which to entertain visitors.

... so always take his advice with this in mind.

Basically, get a mansion.

Thank-you for your contribution Chebby.

You are the tricky one aren't you?

You know full well (because the URL has not changed but the photo has) that the photo I posted was of your Bozak speakers. (With a pair of Linn Isobariks and racks of LPs.)

(Google images still had the thumbnail pic cached.)

Obviously you have spoilt your posting on Pink Fish too (where I got the photo URL from) as a result of trying to make it look like I posted the dung picture...

http://www.pinkfishmedia.net/forum/showthread.php?t=67564 (post #13) *

It was originally (before your devious photo switch) a valid point. You have an enormous Victorian mansion and can spread out lots of vast kit that others (like fr0g) cannot. Your recommendations regarding size of kit must therefore be seen in this light.

Anyway, you have essentially altered/edited my post as a result of the photo switch and only mods have the right to edit posts so please don't do it again.

 

[hoopsontoast]

I love it how DIY’ers come on forums like this and think they no better than the respective manufacturer. A manufacturer will spend thousands researching and testing a product only for a DIY’er to come along with a handful of watts and a driver that was optimised back in 1973 and think they know better.

Potty the lot of them …

Whoa there darling, I was merely pointing out that the driver in the AVI sub is nothing but pretty standard for that kind of application, and that design as used by a lot of other people, as I pointed out.

Not sure what the handfull of watts and a driver from 1973 has to do with anything? :roll:

FWIW I dont think I know better than AVI, I have looked into it and I certainly could not form a sucessfull speaker company, I would not make any money.

It just amused me that for a company that is entirely objective would back up their speakers with purely subjective opinion, and fans/customers of said company would base a drivers potential performance on how a driver looks, rather than any measureable parameter.

 

[Alec]

for a company that is entirely objective

Oh, I dunno. They get people with golden ears to listen to products before they leave the factory.

 

[fr0g]

Perhaps I should have included the fact that divorce was not an option.

Be thankful he didn't recommend these...

(Lindsayt's Bozak B-4000s dwarfing some compact stand-mount speakers.)

However, it is worth noting that Lindsayt has the good fortune to be able to spread all this kit out in his Victorian mansion ...

Living in a Victorian mansion helps in blending-in large vintage hi-fi kit and giving the wife a choice of rooms in which to entertain visitors.

... so always take his advice with this in mind.

Basically, get a mansion.

Thank-you for your contribution Chebby.

You are the tricky one aren't you?

You know full well (because the URL has not changed but the photo has) that the photo I posted was of your Bozak speakers. (With a pair of Linn Isobariks and racks of LPs.)

(Google images still had the thumbnail pic cached.)

Obviously you have spoilt your posting on Pink Fish too (where I got the photo URL from) as a result of trying to make it look like I posted the dung picture...

http://www.pinkfishmedia.net/forum/showthread.php?t=67564 (post #13) *

It was originally (before your devious photo switch) a valid point. You have an enormous Victorian mansion and can spread out lots of vast kit that others (like fr0g) cannot. Your recommendations regarding size of kit must therefore be seen in this light.

Anyway, you have essentially altered/edited my post as a result of the photo switch and only mods have the right to edit posts so please don't do it again.

To be fair aesthetically speaking there isn't much in it

 

[Alec]

What are the Tannoys you mentioned, fr0g?

 

[John Duncan]

for a company that is entirely objective

Oh, I dunno. They get people with golden ears to listen to products before they leave the factory.

(sigh)

 

[Alec]

for a company that is entirely objective

Oh, I dunno. They get people with golden ears to listen to products before they leave the factory.

(sigh)

Hmmm?

 

[alienmango]

I love it how DIY’ers come on forums like this and think they no better than the respective manufacturer. A manufacturer will spend thousands researching and testing a product only for a DIY’er to come along with a handful of watts and a driver that was optimised back in 1973 and think they know better.

Potty the lot of them …

well..... lets be honest, in terms of sub design......... this (in a sealed cabinet) http://www.parts-express.com/pe/showdetl.cfm?partnumber=293-666

with a minidsp ($100) and a powerful enough amp will beat any product on the market at any price. Let me know if you can find a better performing product at any price, total cost is going to be under £1500.

 

[davedotco]

Building loudspeaker drive units is a complex skill, it requires expertise in many different disciplines, many of them far more complex than the shape or style of the basket.

Think about it, are you really going to melt alloy and form your own baskets, with all the work that entails just to reinvent the wheel?

Same with ferrite magnets, you virtually buy them by the pound, rectangular cross section wire for edge wound voicecoils, are you really going to draw your own?

Almost all of the obvious parameters are open to interpretation and poor implementation can easily turn a silk purse into a pigs ear.

If you are 'building' you own drive units then, unless you have some very unusual requirements or are looking to make a visual statement (like the Volts) then you concentrate on putting the important bits together, the ones that make a real difference.

 

[alienmango]

Building loudspeaker drive units is a complex skill, it requires expertise in many different disciplines, many of them far more complex than the shape or style of the basket. Think about it, are you really going to melt alloy and form your own baskets, with all the work that entails just to reinvent the wheel? Same with ferrite magnets, you virtually buy them by the pound, rectangular cross section wire for edge wound voicecoils, are you really going to draw your own? Almost all of the obvious parameters are open to interpretation and poor implementation can easily turn a silk purse into a pigs ear. If you are 'building' you own drive units then, unless you have some very unusual requirements or are looking to make a visual statement (like the Volts) then you concentrate on putting the important bits together, the ones that make a real difference.

Vector calculus, electromagnetism, being able to model the heat equation pde, fourier analysis of cone break up/basket vibration etc, multivariate optimisation over time, matlab....it's not that complex really, just basic maths/physics.

Obviously you're completely right, putting together high quality parts well is the real skill, but there's rarely a need to get a custom unit as there are so many high quality parts available.

It amazes me there's so much "research" going on all the time at all these hifi companies. How many iterations of the same quality drive units do we really need in this world?

 

[John Duncan]

for a company that is entirely objective

Oh, I dunno. They get people with golden ears to listen to products before they leave the factory.

(sigh)

Hmmm?

For a company which trumpets its objectivity and its engineering capability (and derides every other manufacturer of hifi for having neither), its product assessments do appear to rely heavily on the opinions of 'golden-eared experts' and user reviews, whilst providing zero measurements to back it up.

 

[Alec]

Indeed. see, whereas you can measure amps and DACs, speakers not so much, apparently.

Oh will you look at that; I've become you

 

[John Duncan]

Indeed. see, whereas you can measure amps and DACs, speakers not so much, apparently.

Incorrect. You can measure them, it's just that we wouldn't understand the results...

 

[davedotco]

Building loudspeaker drive units is a complex skill, it requires expertise in many different disciplines, many of them far more complex than the shape or style of the basket. Think about it, are you really going to melt alloy and form your own baskets, with all the work that entails just to reinvent the wheel? Same with ferrite magnets, you virtually buy them by the pound, rectangular cross section wire for edge wound voicecoils, are you really going to draw your own? Almost all of the obvious parameters are open to interpretation and poor implementation can easily turn a silk purse into a pigs ear. If you are 'building' you own drive units then, unless you have some very unusual requirements or are looking to make a visual statement (like the Volts) then you concentrate on putting the important bits together, the ones that make a real difference.

Vector calculus, electromagnetism, being able to model the heat equation pde, fourier analysis of cone break up/basket vibration etc, multivariate optimisation over time, matlab....it's not that complex really, just basic maths/physics.

Obviously you're completely right, putting together high quality parts well is the real skill, but there's rarely a need to get a custom unit as there are so many high quality parts available.

It amazes me there's so much "research" going on all the time at all these hifi companies. How many iterations of the same quality drive units do we really need in this world?

Most speaker companies that 'build' their own speakers are really just assemblers, basket and magnet from here, cones from there, polepieces from somewhere else. However the variations that can be run with even quite standard 'components' is what I really meant by saying complex.

Playing with cones of different weights and stiffness, optimising voice coil gaps and flux density are just a couple of simple ways that manufactures can use to 'individualise' their products whilst still using 'standard' components and in a competitive market, that is important.

There is some "research" going on, the resurgence of ribbon tweeters being an obvious one, the emergence of small, powerful magnet assemblies that are actually affordable seems to be the driving force here, interesting to see where it goes.

 

[Alec]

Pretty sure he said as much to me but ill not be going to check.

 

[JMacMan]

for a company that is entirely objective

Oh, I dunno. They get people with golden ears to listen to products before they leave the factory.

(sigh)

Hmmm?

For a company which trumpets its objectivity and its engineering capability (and derides every other manufacturer of hifi for having neither), its product assessments do appear to rely heavily on the opinions of 'golden-eared experts' and user reviews, whilst providing zero measurements to back it up.

I have golden ears, but wasn't invited to listen and advise..

JB

 

[JMacMan]

Indeed. see, whereas you can measure amps and DACs, speakers not so much, apparently.

Incorrect. You can measure them, it's just that we wouldn't understand the results...

I do seem to recall hearing this from them.... many times....lol

JB

 

[John Duncan]

I have golden ears, but wasn't invited to listen and advise..

JB

I think you'll find that's because "You're blind or you don't understand the measurements" (though admittedly that was while he was saying Class D - the technology used in their new speaker, if I recall - is rubbish).