Hey, I'm JR, training manager here at Crutchfield, and these are Audiofrog amplifiers. The A600.1D
is a mono subwoofer amplifier, and the A150.4D is a four-channel amplifier, so you can use these
to power all of the speakers in your system. Audiofrog is a company that was started by
people that have done installs, and they've created hardware that makes installation of speakers and
amplifiers easier. It helps their amplifier design. They've also designed DSP algorithms so they know
how to shape the sound and make it sound great. These are very powerful amplifiers despite being
very very small, like the size of a small paperback book. The four-channel is 100 watts by 4 into 4
ohms; if you put 2-ohm speakers on it it will go to 150 watts. And Audiofrog is known for rating
their amplifiers conservatively, so it will put out at least that much power. The sub amp is 600 watts
into a 2-ohm sub, which is most likely how you're going to wire your sub, and it's a powerhouse of an
amplifier despite its really small size. What makes these amplifiers so small and powerful
is Class-D technology. Sometimes it gets a bad rap for not sounding as clean as a Class-A/B
amplifier. The guys at Audiofrog have absolutely figured that out. The switching technology inside
these amplifiers is super fast and super quiet. The output filters that you need on a Class-D
amplifier are well above the range of human hearing, so you're not going to hear those, either.
They're also super great at rejecting noise. They do that a couple different ways. The heat sink on
the top not only dissipates heat but also acts as a shield that rejects EMI, or electromagnetic
interference. Noise. You don't want to hear it. These amps reject it. The inputs are also great at
rejecting noise. They have both preamp-level inputs for connecting to an aftermarket radio and high-
level or speaker-level inputs for connecting to your factory radio. These speaker-level inputs can
handle up to 30 volts of input, which means they'll even work with the output from a factory amplified
system, so you can really hook them up to just about any vehicle's factory radio or amplifier.
You can also use an auto turn-on feature with these high-level inputs. It can do signal sensing
or DC offset, or of course you can just use the remote in on the amplifier to turn it off and on.
Audiofrog uses differential audio inputs. Those are the inputs where the music comes into the
amplifier. It's like having a balanced audio connection. The positive and negative terminals are
not connected to ground; if they were, that would be a great way to introduce noise into the
system. Since they're not, super clean, rejects noise, especially if you're using twisted-pair RCA cables.
All of this results in a signal-to-noise ratio that's very high. A lot of signal, not much noise.
108 dB signal to noise ratio on the sub amp, 102 dB on the four-channel. All of that technology
gives you a total harmonic distortion or THD of 0.1%, which is well below human hearing. Let's talk
crossovers. The sub amp has a variable low-pass crossover from 50 to 500 Hz, so that you can
dial it in based on the size and performance of your subwoofer. There's also a subsonic filter to
take out all those super-low frequencies that just waste away amplifier power that you can't
hear as music. You can adjust that anywhere from 5 to 40 Hz. There's also variable bass boost.
The sub amp also has variable phase control, so if the bass isn't hitting quite right in your car
instead of having to move your subwoofer you can adjust the phase of the subwoofer
right from the amplifier. You don't see that on too many sub amps, and that's because these were
made by installers to make them easier to install. Lastly, you can also get an optional level control
or "bass knob" for the sub amp. It comes with some cable that you plug into the amp, run it up to
your driver's seat so that you have a knob to adjust your bass song by song if you want to.
If you have more than one of the A600.1Ds you can connect them together using a phone cable splitter.
That will allow one knob to control multiple sub amps. The crossovers on the four-channel amp
are completely configurable. You have low pass, you have bandpass, and you have high pass, so no matter
what speaker you're powering with this amplifier there's the right crossover in the amplifier. If
you're powering subs, you can block out all of the highs. If you're powering a tweeter, you can
block out all of the lows. If you're powering a mid-range speaker, you can block out the highs
and the lows. You can also completely turn the crossover off if you're using your own external
DSP, and the 4-channel amp can be configured as a 2-channel amp, a 3-channel amp, or a 4-channel amp.
It's a powerhouse, and it's very configurable. You can do whatever you need to with it.
So if you're looking for a small, clean powerhouse of an amplifier,
you certainly might want to consider these two Audiofrogs. If you have any questions about them
or what amps you might need for your car, get in touch with us. Go to crutchfield.com/contact;
there you'll see you can call us, you can chat with our advisors, we have live advisors standing
by to help you get the right amps for your car. You can also post your questions right
here on this YouTube video. We do look at those and we will respond accordingly. And you're on
YouTube, so you know what to do. Like, subscribe, and turn on those notifications. Thanks for watching.