Nousaine wrote:

The 80 Hz bandlimit for example. Most manufacturers claim 60 - 80 Hz for
satellites when, in use, they often cannot produce realistic low
distortion SPL
anywhere near the bandlimit. As an ilustration I recently measured a more
expensive satellite system with a spec'd lower bandlimit of 36 Hz.

When driven with 2.8 volts and measured at 2-meters the system is -3 dB
at 83
Hz and when driven to full output (10% distortion) it will only produce
70 dB
SPL @ 62 Hz. This system has 2 6.5-inch woofers in it. And it's one damn
fine
speaker but it's 'specifications' do not describe real performance. It
basically is an "80-Hz" system.

Sure, but could Paradigm sell a bookshelf speaker for $1100 US a pair if
they admitted that it was only flat down to 83 dB? Course not, because all
their competitors are reporting "best-case" FR.

Audiophiles throw around published specs all the time--even the ones who
insist that "specs are meaningless"! If they only knew...

bob

__________________________________________________ _______________
Get tax tips, tools and access to IRS forms – all in one place at MSN Money!
http://moneycentral.msn.com/tax/home.asp

"Bob Marcus" wrote:

Nousaine wrote:

The 80 Hz bandlimit for example. Most manufacturers claim 60 - 80 Hz for
satellites when, in use, they often cannot produce realistic low
distortion SPL
anywhere near the bandlimit. As an ilustration I recently measured a more
expensive satellite system with a spec'd lower bandlimit of 36 Hz.

When driven with 2.8 volts and measured at 2-meters the system is -3 dB
at 83
Hz and when driven to full output (10% distortion) it will only produce
70 dB
SPL @ 62 Hz. This system has 2 6.5-inch woofers in it. And it's one damn
fine
speaker but it's 'specifications' do not describe real performance. It
basically is an "80-Hz" system.

Sure, but could Paradigm sell a bookshelf speaker for $1100 US a pair if
they admitted that it was only flat down to 83 dB? Course not, because all
their competitors are reporting "best-case" FR.

Audiophiles throw around published specs all the time--even the ones who
insist that "specs are meaningless"! If they only knew...

bob

Yes; everybody gets caught up in the numbers game. IME this nowhere more
evident in the powered subwoofer "amplifier" ratings. Speaker power ratings,
especially in aftermarket car audio, are in that same league.

Published low frequency bandwidth spec's in loudspeakers are rarely
accurate. The "specifications may vary" caveat allows for some huge fudge. I
think the last remark is correct, the published figures are probably based
on market aims since nearly everyone does it.

Wessel

"Bob Marcus" wrote in message
...
Nousaine wrote:

The 80 Hz bandlimit for example. Most manufacturers claim 60 - 80 Hz for
satellites when, in use, they often cannot produce realistic low
distortion SPL
anywhere near the bandlimit. As an ilustration I recently measured a
more
expensive satellite system with a spec'd lower bandlimit of 36 Hz.

When driven with 2.8 volts and measured at 2-meters the system is -3 dB
at 83
Hz and when driven to full output (10% distortion) it will only
produce
70 dB
SPL @ 62 Hz. This system has 2 6.5-inch woofers in it. And it's one
damn
fine
speaker but it's 'specifications' do not describe real performance. It
basically is an "80-Hz" system.

Sure, but could Paradigm sell a bookshelf speaker for $1100 US a pair if
they admitted that it was only flat down to 83 dB? Course not, because all
their competitors are reporting "best-case" FR.

Audiophiles throw around published specs all the time--even the ones who
insist that "specs are meaningless"! If they only knew...

bob

__________________________________________________ _______________
Get tax tips, tools and access to IRS forms - all in one place at MSN
Money!
http://moneycentral.msn.com/tax/home.asp

In article Ka2bc.52994$gA5.678597@attbi_s03, Nousaine wrote:

Yes; everybody gets caught up in the numbers game. IME this nowhere more
evident in the powered subwoofer "amplifier" ratings.

I've also noticed in your reviews in Sound and Vision that the
actual crossover frequencies often have little to do with the
labeling on the adjustment.

Have you ever tested the PartsExpress.com subwoofer amplifiers? My old
Phase Tech PC-50 passive subwoofer has recently been relegated to use
in the back room (11'x11'), and not surprisingly sounds boomy there.
I want to put it in a corner and use a separate amplifier to control
its output without spending a whole lot of money. The Parts Express
amps would seem to do the job, if the numbers can be trusted. The
other option would be to try to get an NHT SA-1 or similar on eBay.
(Bypassing the crossover on the PC-50 will be trivial.)

In article Ka2bc.52994$gA5.678597@attbi_s03, Nousaine wrote:

Yes; everybody gets caught up in the numbers game. IME this nowhere more
evident in the powered subwoofer "amplifier" ratings.

I've also noticed in your reviews in Sound and Vision that the
actual crossover frequencies often have little to do with the
labeling on the adjustment.

Have you ever tested the PartsExpress.com subwoofer amplifiers? My old
Phase Tech PC-50 passive subwoofer has recently been relegated to use
in the back room (11'x11'), and not surprisingly sounds boomy there.
I want to put it in a corner and use a separate amplifier to control
its output without spending a whole lot of money. The Parts Express
amps would seem to do the job, if the numbers can be trusted. The
other option would be to try to get an NHT SA-1 or similar on eBay.
(Bypassing the crossover on the PC-50 will be trivial.)

Jim West wrote:

Nousaine wrote:

Yes; everybody gets caught up in the numbers game. IME this nowhere more
evident in the powered subwoofer "amplifier" ratings.

I've also noticed in your reviews in Sound and Vision that the
actual crossover frequencies often have little to do with the
labeling on the adjustment.

This is often true.But remember I'm referencing this to the acoustical sound
pressure that comes out of the subwoofer and not the electrical response of the
electronic portion of the product.


Have you ever tested the PartsExpress.com subwoofer amplifiers?

No I haven't.

My old
Phase Tech PC-50 passive subwoofer has recently been relegated to use
in the back room (11'x11'), and not surprisingly sounds boomy there.
I want to put it in a corner and use a separate amplifier to control
its output without spending a whole lot of money. The Parts Express
amps would seem to do the job, if the numbers can be trusted. The
other option would be to try to get an NHT SA-1 or similar on eBay.
(Bypassing the crossover on the PC-50 will be trivial.)

The Paradigm X-30 standalone crossover is pretty good for $160 but you'll need
a separate amplifier. If you acquire a Partsexpress product be sure to report
back on what you find.