Originally Posted by SaviorMachine
My outsider's perspective on Chase owners? They seem to be mostly DIYers with a lot of technical knowledge, who aren't thrown by gimmicks and marketing.
Actually, I think the only reason I ended up being a Chase owner was because I was thrown by gimmicks and marketing.
Their sealed 18 line was advertised as 23Hz -200Hz +/-3dB, and it all started with this graph:
I've overlaid a +/-3dB window, and provided the rough bottom points as they land in this window.
Here's the current (as of last week) explanation for this graph:
"That was based on a computer model almost a year before we had the first SS series subwoofer built. A look at my actual words were "with the LT circuit built in", which was what we had hoped for with the original Dayton amp. That strong an eq curve never ended up happening."
Yet in 2011, after the second
series of this line of subs had already been released, that same exact yellow (simulated) line was presented with this explanation:
"Here is the sim of the response curve with bass boost on."
Yes, it was presented that the 23-24Hz bottom end (-6dB point) was achieved using the Dayton SA1000 and it's "Bass Boost" switch set to the "ON" position.
Of course, to anyone with a little "technical knowledge" you'd realize that a true LT circuit, even modeled in WinISD will never have a weird hump in it's response. A PEQ boost can only explain that hump.
So if you look at the white line provided in the sim as the naked response and compare that to the yellow line which is presented as "Bass Boost ON" with the Dayton amp, you start to scratch your head.
The "Bass Boost" switch on the Dayton amp applies a 3dB boost centered at 25Hz with Q=1.4. But do this mentally, and you can see the white line will never become the yellow line. What happened? Well, it was fudged. The top end was lopped off with a LPF to cut down on the roll-off, and then the PEQ boost was applied to the simulation. Compare the roll-off of the top end of the white line to the yellow line. You can see this pattern in other measurements provided by Chase over the years- LPF applied to the top end to mask the significant roll-off.
Proving this as more than speculation of course, is this close-mic measurement comparing the naked response of a sealed Chase 18 to one with the "bass boost" switch enabled, resulting in (as expected) roughly +3dB @ 25Hz Q=1.4 on spec, and giving us a -6dB point of 36Hz.Nowhere near 23Hz.
Do you think nearly as many sealed 18 subs would have been sold if the spec was 36-200Hz +/-3dB with EQ? Of course not, nearly all HT sealed subs target a low 20's -6dB point.
The original specification, whether intentionally or not, was derived from a fudged WinISD simulation!
You can still find remnants of this errant specification on their current website, for example the SS-18.1 product page:
"The SS-18.1 has a response curve of +/- 3 dB from 23 Hz to 200 Hz with a natural, 12dB per octave roll-off below 23 Hz to match room gain."
It remained this way until some point in the last year, where you can now find a silent change to the specification on the website:
"21Hz – 100Hz +/- 5 dB (Using the Dayton Amp and the bass boost switch is ON)"
So instead of owning up to a misleading specification and giving everyone an explanation for the revision, they silently change the spec closer toward reality, yet realize they still must have a low 20's number to compete with other sealed lines. So they decide that most folks will probably see that 21Hz number and miss the fact that they have a very unusual +/-5dB rating.
We've now moved from 23Hz being -6dB to 21Hz being -10dB! (As you can see from the close-mic I posted, the bass boost for the Dayton will not even provide this response either, it's -15dB down at 21Hz!)
To further compound this misleading mess, we have a new 2013 explanation from Chase for those original specs:
" I have always specified the unit as +/- 5 dB from 21 to 100 Hz. That was the specification noted in the specifications section of the subwoofer. There was no "silent change" made."
"I DID NOT write the 23 Hz spec. It really is that simple."
Well, we already know from the facts presented that this isn't the case, 23Hz was the spec for a long time, but here is a very clear quote from Chase Home Theater that shows how false those statements really are:
"Now, let's look at our specs. We have told people from day one to expect a 3 dB down point at 23 Hz with the Dayton bass boost employed, and a 12 dB per octave roll off below that point."
There's good reason why other subwoofers get more discussion here. This is just one of many.