Confused: set gains w/Sub setting at "0" or "+15"?

[bgowdy 5,000+ posts]

see this HU pre out stufff confuses me. i have a pioneer and i kno mine pre outs are like 2.5 if im not mistakin. which i think is pretty low compared to other HU

 

[40oz 10+ year member]

agreed. the head unit manual should say if the adjustment is an EQ boost and it should tell at what frequency the boost is at.
Alpine has a bass level and a subwoofer level. bass level is an EQ (at 100Hz typically, unless parametric "bass engine pro"). subwoofer level is signal strength on that preout. this should be universal terminology but some companies do strange things. it is important to know what your HU is actually doing.

My head unit (Kenwood KIV-701) manual doesn't specify what the "Subwoofer Level" does exactly. Is it safe to assume that it is an EQ boost rather than adjusting the signal strength, since it is a Kenwood and doesn't have a separate "Bass Level" adjustment?

 

[keep_hope_alive Premium Member]

My head unit (Kenwood KIV-701) manual doesn't specify what the "Subwoofer Level" does exactly. Is it safe to assume that it is an EQ boost rather than adjusting the signal strength, since it is a Kenwood and doesn't have a separate "Bass Level" adjustment?

6ch/4V Preamp Outputs: The KIV-701 features front, rear and subwoofer 4-volt preamp outputs. The front and rear speaker preamp outputs are balance and fade adjustable. The subwoofer preamp output is non-fading. The front, rear, and subwoofer preamp outputs are fixed to the rear chassis of the head unit. The subwoofer preamp output features an independent level control (-15 to +15).

I'd have to guess that you won't achieve a 4V output without the level on +15. hard to say without a 0dB track an a scope.

It has a separate 5-band EQ so it's not a bass level. bass level is EQ.

 

[keep_hope_alive Premium Member]

see this HU pre out stufff confuses me. i have a pioneer and i kno mine pre outs are like 2.5 if im not mistakin. which i think is pretty low compared to other HU

It just means you need more amplifier gain than someone who has a 4V head unit. the same power can be achieved from most amps.

now, if you get an amp that can only make rated power with a max voltage input, -0dB source recording, gain at max, and supply voltage of 15+VDC, then you'll never get rated power. but that's how cheap amps are rated. any decent amp will do just fine with 2V or less.

The real concern with lower HU preout voltage is noise. the higher your amp gain is, the more noise you will have.

 

[bgowdy 5,000+ posts]

It just means you need more amplifier gain than someone who has a 4V head unit. the same power can be achieved from most amps.
now, if you get an amp that can only make rated power with a max voltage input, -0dB source recording, gain at max, and supply voltage of 15+VDC, then you'll never get rated power. but that's how cheap amps are rated. any decent amp will do just fine with 2V or less.

The real concern with lower HU preout voltage is noise. the higher your amp gain is, the more noise you will have.

ok with that said do you know anything about the soundstream dtr1.3400's

 

[40oz 10+ year member]

6ch/4V Preamp Outputs: The KIV-701 features front, rear and subwoofer 4-volt preamp outputs. The front and rear speaker preamp outputs are balance and fade adjustable. The subwoofer preamp output is non-fading. The front, rear, and subwoofer preamp outputs are fixed to the rear chassis of the head unit. The subwoofer preamp output features an independent level control (-15 to +15).
I'd have to guess that you won't achieve a 4V output without the level on +15. hard to say without a 0dB track an a scope.

It has a separate 5-band EQ so it's not a bass level. bass level is EQ.

Nice, thanks. I forgot Crutchfield had such a detailed review.

So since it is a level adjustment, I can safely put it at +15 without worrying about clipping? Or should I stay safe and set it with it at +10?

 

[40oz 10+ year member]

Well I emailed Kenwood and this was their response:

"I understand you are inquiring about the SUBWOOFER LEVEL on your KIV-701. This is an equalizer setting for the frequency and does not affect the output voltage. "

 

[keep_hope_alive Premium Member]

then ask them what frequency it boosts and what the Q is of the filter. if it is an EQ then they have to tell you those two things.

that response sounds like an Indian wrote it.

 

[av83 10+ year member]

that response sounds like an Indian wrote it.

I agree.

 

[av83 10+ year member]

I wasn't all that satisfied by the answer a guy at a local kenwood dealer/install shop told me over the phone. But he did say that the headunit will not send a clipped signal to the amp via sub rca due to the subwoofer level being on +15. That was in regards to my x994.