BillFitzmaurice.info

Haha! Thanks Seth!
By 90dBA, I meant for anything above, say, 100 hz., and then fill in with the sub. But, your numbers do show how much gain there is in a vehicle. I think it also shows that I was reasonably close when considering the equal loudness curve. Granted, some of us like a whole lot more of the "below 100 hz".

Anyway....thank you.

dBA will read lower than dBC, not higher.

Have you got a driverack? Or a DCX/DEQ combo? I only ask because you can change the DEQ setting to A B C or (my favourite) OFF.
I haven't explored my PA2 enough to see if I can alter anything there yet...

Bill Fitzmaurice wrote: ↑Sun May 03, 2020 9:10 pm dBA will read lower than dBC, not higher.

That's counter to the story you once told about a venue that was too loud and getting complaints about the bass. IIRC, whoever set up their warning system used dBc, the warning light never indicated
a too loud condition, and simply by switching to dBa you were able to solve their problem.

That says to me, that for any given number on the scale (bass region) dBa will be quieter. A 30Hz 100 dBa tone would be quieter than a 30Hz 100dBc tone. Correct?

But, the same tone of an unknown amplitude value in the dBa will read higher than dBc. Otherwise, your story wouldn't have worked out the way it did.

Or, am I just all kinds of confused?

Let me try again... 100dBc is too loud. You switch it to dBa and it reads lower? So, you can then turn it up more? That doesn't make sense. dBa has to read higher.

Grant Bunter wrote: ↑Sun May 03, 2020 9:30 pm Have you got a driverack? Or a DCX/DEQ combo? I only ask because you can change the DEQ setting to A B C or (my favourite) OFF.
I haven't explored my PA2 enough to see if I can alter anything there yet...

I have DEQ/DCX, although they weren't used. I used the DSP built into the amp.

I wonder if "off" is essentially dBZ?

SethRocksYou wrote: ↑Sun May 03, 2020 9:37 pm That's counter to the story you once told about a venue that was too loud and getting complaints about the bass. IIRC, whoever set up their warning system used dBc, the warning light never indicated

You have it backwards.

The reason that I asked for dBA was to NOT account for the bass region. I didn't want the sub-100hz to affect the measured level.

I want to be clear that I don't see this as any sort of malfunction. It's not something that can be heard at all under normal use. I think it's pretty cool. Evidence of just how much air this thing is moving.
As if the thunder in the car wasn't enough evidence.

Anyway, see... sounds like a dryer vent

Bill Fitzmaurice wrote: ↑Sun May 03, 2020 9:52 pm

SethRocksYou wrote: ↑Sun May 03, 2020 9:37 pm That's counter to the story you once told about a venue that was too loud and getting complaints about the bass. IIRC, whoever set up their warning system used dBc, the warning light never indicated

You have it backwards.

Are you sure?

I was there, I'm quite sure. Look at a dBA versus dBC chart.

Bill Fitzmaurice wrote: ↑Sun May 03, 2020 10:07 pm I was there, I'm quite sure. Look at a dBA versus dBC chart.

You're right, I do have it backwards. Slightly embarrassing. Annnnnd I'm over it.

So, in the absence of a dBz meter, dBc is the next best for audio. And dBa's the one we don't really use for audio stuff. Why was I thinking about that the other way around? Oh well. Thanks for the correction and the manner in which you did so. Appreciated.

Now that my mind's straight the numbers I got look better than before.

SethRocksYou wrote: ↑Sun May 03, 2020 9:39 pm

Grant Bunter wrote: ↑Sun May 03, 2020 9:30 pm Have you got a driverack? Or a DCX/DEQ combo? I only ask because you can change the DEQ setting to A B C or (my favourite) OFF.
I haven't explored my PA2 enough to see if I can alter anything there yet...

I have DEQ/DCX, although they weren't used. I used the DSP built into the amp.

I wonder if "off" is essentially dBZ?

I’m not sure, I’d have to check out the manual.

Where I was going was to use the metering section of the DEQ, via RTA input.
I run with no weighting so I get a true value, rather than a reading which requires me to remember which part of the slope, in which curve I’m in, to work out the significance.

sorry for the distraction though...

dBZ meters are rare, because they're expensive. They're expensive because they need to be able to measure flat to 10Hz. If something like a metering section of a DEQ isn't specified as dBC it's probably flat to the lowest EQ frequency.

SethRocks that's a very cool build- using two drivers mounted on the side panel. Perhaps the TAT should should also be called the "Trunk Auto Tuba."
How many liters does that move.

I have been making progress with my kei van project- 6" depth.

I am tempted to try my Exodus Anarchy TH in this also. It's an 8ohm.

I still have a pair of those drivers in 4ohm but wanted to save them for a 2-way TL or MLTL one day.

iSurfSouthChinaSea wrote: ↑Mon May 04, 2020 10:39 pm SethRocks that's a very cool build- using two drivers mounted on the side panel. Perhaps the TAT should should also be called the "Trunk Auto Tuba."
How many liters does that move.

I have been making progress with my kei van project- 6" depth.

I am tempted to try my Exodus Anarchy TH in this also. It's an 8ohm.

I still have a pair of those drivers in 4ohm but wanted to save them for a 2-way TL or MLTL one day.

Nice job. Your TruckTuba came out necely. Have you given it a listen?