Sure TA2024 - Can I get a bit more volume?

[squirrelbob]

I'm currently using a TA2024 to power a couple of Infinity 612m speakers. The power source is a 12v 9ah SLA battery. The speakers are enclosed in PVC pipe and are not currently ported.

The volume level is almost where I want it, but could use a slight boost. I'm certainly not an expert when it comes to amplifiers/speakers, so I thought I'd ask you guys what the best way to eek out a bit more volume would be.

I have a TPA3123 as well, which I tried using instead of the TA2024, but it didn't seem to improve the volume at all.

I think if I doubled up the battery and ran two in series for 24v it would be a pretty big boost, but this is a bicycle stereo project so weight is a concern.

I'm definitely not opposed to considering a different amp or different speakers, so any advice would be appreciated.

[Bone]

You need more input signal. What are you driving it with at the moment?

[Saturnus]

As all other car audio speakers, yours aren't suited for mobile stereo use as sensitivity is far too low.

Infinity's own specification says:

Infinity 612m Specifications
Power Handling, RMS: 75 Watts
Power Handling, Peak: 225 Watts
Sensitivity (2.83V @ 1m): 92dB
Frequency Response: 50Hz – 20kHz
Impedance: 4 Ohms
Mounting Depth: 2-5/8 inches

So that 89dB/w/m (2.83V into 4 ohm is 2 watts) but car audio speaker are always specified at peak sensitivity, so average real life could easily be 2 dB lower.

You need speakers that have higher sensitivity and being able to handle the intended use. Pro drivers are basically the only ones that do that but unfortunately there isn't much choice in smaller pro drivers.

[squirrelbob]

Originally Posted by Bone

You need more input signal. What are you driving it with at the moment?

Using an iPod as the source.

[squirrelbob]

Originally Posted by Saturnus

You need speakers that have higher sensitivity and being able to handle the intended use.

So, based on some reading, my understanding is that a 3 dB increase in sensitivity amounts to about double the volume, so I want to look for speakers in the 94-95 dB sensitivity range?

[Saturnus]

Originally Posted by squirrelbob

So, based on some reading, my understanding is that a 3 dB increase in sensitivity amounts to about double the volume, so I want to look for speakers in the 94-95 dB sensitivity range?

Actually it's +6dB for double SPL but the reasoning is still the same. You current speakers are roughly 88dB/w/m, so you need to look for speaker with at least 3dB higher sensitivity, if possible even more, and preferably still 4 ohms but that's difficult to find for a reasonable amount of money, and for the intended use, in small speaker sizes as pro driver under 10" are generally midrange drivers, although exceptions do exist.

[Michael Bean]

Actually, no, 6dB won't double the apparent sound level, the human ear works logarithmically, so to double perceived sound level requires about 10 times the power or 10 dB.

Mike

[Saturnus]

Originally Posted by Michael Bean

Actually, no, 6dB won't double the apparent sound level, the human ear works logarithmically, so to double perceived sound level requires about 10 times the power or 10 dB.

Who wrote anything about the apparent sound level? It's not even relevant really.

The apparent sound level comes into play when we increase volume to the point where we percieve the sound as twice as loud but there are many other factors that come into play in apparent sound level. This isn't the case here. We're talking sensitivity, and actual SPL.

[Michael Bean]

Who wrote anything about the apparent sound level? You did, "Actually it's +6dB for double SPL" in response to "So, based on some reading, my understanding is that a 3 dB increase in sensitivity amounts to about double the volume". And it's a 3dB increase that doubles the power, 6dB quadruples it.

Mike

[Saturnus]

Originally Posted by Michael Bean

Who wrote anything about the apparent sound level? You did, "Actually it's +6dB for double SPL" in response to "So, based on some reading, my understanding is that a 3 dB increase in sensitivity amounts to about double the volume". And it's a 3dB increase that doubles the power, 6dB quadruples it.

/facepalm