60HZ 0 db test tone cranked to the max, no audible change

[eharri3 10+ year member]

I did the gain setting process by ear using a 1K hz , 0 db test tone on my speaker amp last week. Took ten minutes and was very simple: Put everything flat, put HU at max undistorted volume, adjust gain until tone changes, back of a smidge, and voila! DONE!

Then lately after struggling to get that midbass and lower midrange out of my system that never seemed to be there I tweaked the gains on my sub amp and that 10 in sub has come alive, pushing out upper bass tones it never seemed to be capable of before and rounding out that flat spot I seemed to have in the music between the lower, harder-hitting bass tones and the mid range.

So I tried the 'semi-scientific' gain-setting technique today with my sub-amp and a 60 hz, zero db tone. Disconnected the speaker amp, set HU At max undistorted volume, bass boost flat, amp gain at minimal, and turned the sub volume all the way up. Then I popped in test tone, and turned gain to the max with no audible change in the tone. Bumped the volume up a notch, tried it again, still no change in the tone I can detect. Isn't the change supposed to be just as noticable when clipping begins on a sub test tone as it does on the higher speaker-amp tones?

Anyway not wanting to waste any time or hurt anything I took the CD out. I set the gain to just about where I had it when everything started to sound good, about 33% downward from max input sensitivity. This seems to provide the best balance in the system between bass, midbass, and highs without pulling the soundstage to the rear. I'm just curious though: Did I miss something using the test tone that I could have caught with a voltmeter or oscilliscope, or does the fact that the tone didn't change even with the gains all the way up mean that my sub is substantially underpowered?

Reason why I'm asking is, it's a pioneer premier 10'' shallowmount powered by an oldschool soundstream lil wonder rubicon. IT needs 250 watts rms. The guy who gave it to me told me this amp would be more than enough. However, it never got an official wattage rating. Input sensitivity adjustment seems to be the reverse of most amps I've seen in that things get louder as you move the dial to the higher numbers. The highest number isn't even marked so there's no way I can count down by two to match voltage with the HU that way. There's a 1, a 2, a 5, and still about 30% room left to turn the dial after the five to get to the highest gain setting. I downloaded the SS owner's manual, it makes no mention of the exact range of input sensitivity adjustment. It's a really confusing amp and I **** at hearing distortion in regular music so there seems to be no way to properly tune it without an O-scope or something like that.

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[PaulD 10+ year member]

you should be able to clearly hear the distortion with a test tone on the subs just like the 1KHz tone on the mids.

 

[helotaxi 5,000+ posts]

The threshold for hearing distortion is much higher with the lower freqs. The sub itself will introduce a large amount of distortion that will mask clipping, especially at high output levels.

 

[theblizzard2025 10+ year member]

you shouldn't be "listening" for your sub to distort, your supposed to have your volt meter going. Once you get the right voltage (without sub hooked up), your gain is set. The 1k test is great, but only for your speakers. The 60hz audible test, well, honestly your the first person i've heard of that even tried it.

 

[jrwalte 10+ year member]

You can approximately determine the RMS of your amp by doing this test:

Disconnect the neg of your sub so it doesn't play.

Play that 60hz test tone..although 50 would probably be better.

place your DMM on the pos/neg of your amp and read the voltage with the gain turned all the way up.

take the apprx ohm load of your sub and the voltage reading and type it into this calculator

 

[helotaxi 5,000+ posts]

Perhaps you didn't see the "setting by ear" part of the title.

 

[only126db 10+ year member]

Dont only listen for tonal change but physical noise from it's suspension and also when you turn up your gains you will notice the percentage of volume change as you go up, at a certain point the ratio of loudness does not increase as much per turn of dial, at this point you are reaching the amps max....

like this ... 1/8= louder...1/4=alot louder....1/2=way louder......3/4=a little louder..go back to 1/2....little difference between 1/2 and 3/4 try going inbetween the two, be sensible about it, if the change is very minimal stay at the 1/2, it's not worth possible amp/sub destruction for

1db unless you compete.

Of course the position of dial/gain will depend on your input voltage from H/.U.