TheCajunStyle

iTrader: (6)

I have a quick question about the sensitivity ratings on amps.

A few years ago, JBL had a 4-channel amp, the P80.4.
Nowadays, they have its replacement, it's called the GTO75.4.

I used to own the P80.4. I had it bridged to 4 ohms (edit), so it provided 160 watts to channels. I really really loved this amp. I made my infinity 6.1s SCREAM.

edit: It appears the GTO75.5 can also be bridged and provide 284 watts to 2 channels. (but at 4 ohms)

I'm a little concerned that the newer amp isn't as good as the old one for this reason: The senstivity of the new amp is rated at 80dB, while the old amp was rated at 110dB. This is a huge difference. If anyone could shed some light onto this for me, it would be greatly appreciated. I'm curious if the new amp is worth it, or if I should move on to a different manfacturer. Anyone who has experience with these two amps, or anyone who can better explain sensitivity ratings: I need your advice!

Thanks!

StreetOC192

iTrader: (7)

I would NOT put too much stock in ratings from years ago. Today there is a CEA-2006 standard by which amps are rated so everything is equal from manufaturer to manufacturer. You have no idea by what criteria the old JBL amp was measured. I would not hesitate to get a JBL GTO series amp. They are rock solid amps.

Also, this may be just my opinion, but dB ratings on amps are almost useless these days. They used to be listed to show how much musical signal they pass over the noise floor. But in today's electronics, there is greater concern for a high noise floor coming from your source unit and/or a poor install.

Feed an amp a clean signal, it will output a clean signal.

TheCajunStyle

iTrader: (6)

Hmmmm...so assuming the CEA-2006 standard is followed amongst all amp manufacturers, it's now safe to compare JBL vs. Eclipse vs. RF amps just by comparing their RMS values?

StreetOC192

iTrader: (7)

Yes, as long as you see the CEA-2006 seal.......



EDIT: I missed the "just comparing the RMS values" above.....
You want to look at all of the specs as a whole. But the CEA2006 standards give the manufacturers rules to follow when rating their amps so the playing field is more equal.

TheCajunStyle

iTrader: (6)

I really appreciate these answers! Thanks alot StreetOC

DXJP

Not even all RMS values are correct. In fact there are a lot of I.L.S. (If lightning strikes) amps out there. However you can use this to match to speaker power handling ratings.

A low power system with a proper box and install with the correct imaging will always outperform a high power hack job.

I have never been a big fan of JBL car audio and I am not familiar with the unit you are looking at but might I suggest ADS for sound quality. Most of their amps are stable to 2 oms and come in multichannels.

StreetOC192

iTrader: (7)

I hope the info I provided was of some help.

As for the suggestion of A/D/S, you would want to use old A/D/S equipment before they got bought by Directed Audio. Actually I don't think they are marketing amps under the A/D/S name for car audio anymore, are they?