Why do some hi-end speakers lack dual posts?

[Andy Katz]

I've been researching a speaker upgrade and I noticed that the Thiel
PCS and ACI Sapphire (among many others, I'm sure) sport only a single
set of posts. One review commented that the Thiels only needed one
set--specs also stated that the Thiel's crossover was mechanical.

Is that in contrast to passive crossovers?

TIA

Andy Katz
************************************************** *************
Being lied to so billionaires can wage war for profits
while indebting taxpayers for generations to come, now
that's just a tad bit bigger than not admitting you like
the big moist-moist lips of chunky trollops on your pecker.

Paghat, the Rat Girl

[Lionel]

In >, Andy Katz wrote :

> On Thu, 28 Apr 2005 00:06:07 +0200, François Yves Le Gal
> > wrote:
>
>>On Wed, 27 Apr 2005 20:42:33 GMT, Andy Katz >
>>wrote:
>>
>>>Hmmm ... so bi-amping is bunk, then?
>>
>>Bi-wiring isn't bi-amping.
>
> Hmmm, isn't it bi-amping, however, that really sells more product?
> Bi-wiring just requires a bit more wire, right?
>
> Also, if bi-amping is a valid method of improving fidelity, why don't
> high-end speakers such as the Thiel PCS have dual posts?

Just because they decide that you cannot improve the transition between bass
and mid-trebble by bi-amping since they have already done the optimisation
job in the crossover.

http://www.sixmoons.com/audioreviews/thiel/2.4.html

Considering the technical choices I think that they are right...



>>>>Ahem. Bad reviewer, change reviewer.
>>>
>>>Because of the comment about needing only one set, or that it was
>>>mechanical?
>>
>>I would say both.
>
> Actually, I may have misspoke. The part about the mechanical crossover
> may have come from Thiel's own specs/description. I'll have to look it
> up again.
>
> Andy Katz
>
> ************************************************** *************
> Being lied to so billionaires can wage war for profits
> while indebting taxpayers for generations to come, now
> that's just a tad bit bigger than not admitting you like
> the big moist-moist lips of chunky trollops on your pecker.
>
> Paghat, the Rat Girl

[[email protected]]

I have never heard of a "mechanical crossover". I have heard of
mechanical RF filters, such as the Collins, but I can't imagine a
"mechanical crossover" at audio frequencies. It would have to be a huge
thing resembling a radial engine link rod set with double-ended
'marital aids' (Horns-of-Venus, but since lesbians can't marry, should
they be called 'civil union aids'?) with permanent magnets and coils.

Bi-amping is legit, if we are talking true bi-amping, with active
crossover ahead of the power amps, but the high end industry has
avoided it tooth and nail, because they feel most people are too stupid
to make it work and because of warranty claims ignorant users could
easily generate.

Bi-wiring is a crock of ****, pure and simple.

I would be in favor of going to a modern connector such as the Neutrik
SpeakOn, which has also been avoided with vigor by the high end
industry.

[Arny Krueger]

wrote:

> I have never heard of a "mechanical crossover".

AKA "whizzer cone". That's just one example of several possible
implementations.

[severian]

"Arny Krueger" > wrote in message
...
> wrote:
>
> > I have never heard of a "mechanical crossover".
>
> AKA "whizzer cone". That's just one example of several possible
> implementations.
>
>

Also, some older drivers had an anular ring around the center of the driver
(woofer cone), kind of a bend or ring of different density, that acted to
decouple the center of the cone area from the larger rest of the cone with
higher frequencies, reducing the effective size of the driver at HF and
extending HF response. I've seen a number of "3 way" coax older drivers that
have a center mounted horn, and a woofer, and get the 3 way designation
from this kind of decoupling.

[[email protected]]

severian wrote:
> "Arny Krueger" > wrote in message
> ...
> > wrote:
> >
> > > I have never heard of a "mechanical crossover".
> >
> > AKA "whizzer cone". That's just one example of several possible
> > implementations.
> >
> >
>
> Also, some older drivers had an anular ring around the center of the
driver
> (woofer cone), kind of a bend or ring of different density, that
acted to
> decouple the center of the cone area from the larger rest of the cone
with
> higher frequencies,

Yes, but that's not at all what we are talking here, in reference to
something that would give separated electrical outputs to multiple
drivers. The "whizzer" is a better analogy to an engine that has power
outputs at different speeds-such as aux outputs off the camshafts
(Ferrari 4 cam,Detroit 71/92), magneto drive gears (6 cylinder LyCon),
or geared accessory case or jackshafts (Porsche 917 and MB W196).

[Mike McKelvy]

Andy Katz said:

>Hmmm, isn't it bi-amping, however, that really sells more product?
>Bi-wiring just requires a bit more wire, right?

Correct.

>Also, if bi-amping is a valid method of improving fidelity, why don't
>high-end speakers such as the Thiel PCS have dual posts?

Bi-amping needs electronic xovers, to do it properly, one needs the
information on the dcrifers being used and what their rolloff
characteristics are. The best people to do that are the people making
the speaker system. If it's to be bi-amped it should be done by the
designer, not the customer after the fact.

>>>>Ahem. Bad reviewer, change reviewer.

>>>Because of the comment about needing only one set, or that it was
>>>mechanical?


>>I would say both.



>>Actually, I may have misspoke. The part about the mechanical
crossover
>>may have come from Thiel's own specs/description. I'll have to look
it
>>up again.

If by mechanical they mean something other than passive, I'm pretty
sure they would say so, but then advertising is not the same as
instruction manuals.

[Mike McKelvy]

Cal said:


> But the mfr's are not interested-for reasons that actually make
>economic but not tech sense-although this is another good argument to
>DIY speakers in the first place.

There are and have been speakers that were self powered and made for
the consumer rather than the pro audio market.

DIY of powered speakers IMO requires more equipment and expertise than
the typical person building their own speakers will have on hand.

In tech terms, there's no great advantage to powered speakers, at least
in terms of performance. You do get out of having to buy a preamp, but
that's about it. Passive xovers can be implemented to do an excellent
job and power amps are pretty inexpenisve these days for audibly
transparent sound. If one wanted to try his hand at DIY, they should
consider getting one of the good pro amps and replacing the fan with
one of the very quiet ones. There is at least one link I ran across
where this was done with no problem at all.

[ScottW]

"Mike McKelvy" > wrote in message
oups.com...
> Cal said:
>
>
>> But the mfr's are not interested-for reasons that actually make
>>economic but not tech sense-although this is another good argument to
>>DIY speakers in the first place.
>
> There are and have been speakers that were self powered and made for
> the consumer rather than the pro audio market.
>
> DIY of powered speakers IMO requires more equipment and expertise than
> the typical person building their own speakers will have on hand.

Expertise? I think an active crossover is much easier to get right than a
passive power crossover... if nothing else the amp acts as a buffer between
filters and driver eliminating interaction making crossover design pretty
simple.

>
> In tech terms, there's no great advantage to powered speakers, at least
> in terms of performance. You do get out of having to buy a preamp, but
> that's about it. Passive xovers can be implemented to do an excellent
> job and power amps are pretty inexpenisve these days for audibly
> transparent sound. If one wanted to try his hand at DIY, they should
> consider getting one of the good pro amps and replacing the fan with
> one of the very quiet ones. There is at least one link I ran across
> where this was done with no problem at all.

You really f'd up this paragraph. Half your arguments contribute to the
idea that powered (bi or tri amped) speakers are easy and cost effective to
build.

ScottW

[Mike McKelvy]

Scott W said:

>Expertise? I think an active crossover is much easier to get right
than a
>passive power crossover... if nothing else the amp acts as a buffer
between
>filters and driver eliminating interaction making crossover design
pretty
>simple.

Just because the active xover is supposed to be a certain filter type,
doesn't mean it will act that way on a given driver. Without knowing
the rolloff characteristics of the drivers, the active filter could
wind up being worse than a passive one.


> In tech terms, there's no great advantage to powered speakers, at
least
> in terms of performance. You do get out of having to buy a preamp,
but
>> that's about it. Passive xovers can be implemented to do an
excellent
>> job and power amps are pretty inexpenisve these days for audibly
> >transparent sound. If one wanted to try his hand at DIY, they
should
> >consider getting one of the good pro amps and replacing the fan with

> >one of the very quiet ones. There is at least one link I ran across

> >where this was done with no problem at all.

You really f'd up this paragraph. Half your arguments contribute to
the
idea that powered (bi or tri amped) speakers are easy and cost
effective to
build

They can be if you know what you're doing and what the requirements
are, but you simply can't get an off the shelf xover set for a given
slope and expect that it will give you the effect you are looking for.

Without knowing what the drivers are doing at the xover points, you
results will be less than optimum.

[ScottW]

"Mike McKelvy" > wrote in message
oups.com...
> Scott W said:
>
>>Expertise? I think an active crossover is much easier to get right
> than a
>>passive power crossover... if nothing else the amp acts as a buffer
> between
>>filters and driver eliminating interaction making crossover design
> pretty
>>simple.
>
> Just because the active xover is supposed to be a certain filter type,
> doesn't mean it will act that way on a given driver. Without knowing
> the rolloff characteristics of the drivers, the active filter could
> wind up being worse than a passive one.

Yeah but the components needed to tweek an active are pennies.

>
>
>> In tech terms, there's no great advantage to powered speakers, at
> least
>> in terms of performance. You do get out of having to buy a preamp,
> but
>>> that's about it. Passive xovers can be implemented to do an
> excellent
>>> job and power amps are pretty inexpenisve these days for audibly
>> >transparent sound. If one wanted to try his hand at DIY, they
> should
>> >consider getting one of the good pro amps and replacing the fan with
>
>> >one of the very quiet ones. There is at least one link I ran across
>
>> >where this was done with no problem at all.
>
> You really f'd up this paragraph. Half your arguments contribute to
> the
> idea that powered (bi or tri amped) speakers are easy and cost
> effective to
> build
>
> They can be if you know what you're doing and what the requirements
> are, but you simply can't get an off the shelf xover set for a given
> slope and expect that it will give you the effect you are looking for.

For a modest cost you can buy a really versatile digital crossover and tune
away.
http://www.behringer.com/CX3400/index.cfm?lang=ENG

You don't need to know squat about crossovers.

>
> Without knowing what the drivers are doing at the xover points, you
> results will be less than optimum.

And this issue doesn't exist with passive crossovers? Cut the strawman bs.

ScottW