Lanzar Vibe 1200D

The whole goal of this review was to see if this flea market amp did what it clamed.  These amps typically sell for about $200, but I got this one at a bargain price of $160 shipped thanks to the help of all those who contributed on the Phoenix Gold forum.

This amp has a crazy rating system (as most flea market amps do).

1x400W RMS into 4 ohm loads

1x800W max into 2 ohm loads

1x1200W max into 1.3 ohm loads

It has 3 fuses on the side of it, with a 30A rating each.  Included is a remote bass boost, 3 extra fuses, a allen wrench, and the manual.  On board the amp has a 0/180 deg phase switch, aux RCA outputs, a variable low pass filter, and a subsonic filter.  This is a lot of features for only $200.

On the test bench with 14V input, the amp measured 47V RMS of clean output, prior to clipping.  Using a little math one can calculate the theoretical output of this amp:

Now, I am confident it will not meet these numbers, but they are quite impressive nonetheless.

Now consider the fuses.  Let us assume they would blow right at their rated value.  Typically this is not the case, and they would go a bit farther.  Using a wee bit more math:

The amp is probably about 85% efficient due to being a fully Class D design.  So with that in mind:

These numbers hold back the possibility of the actual 1200W output.  However, the amp may be more efficient, and on top of that, I don’t know the actual value at which a standard blade fuse snaps.  If someone knows this info, please inform everyone.  It may be the needed numbers to make up for the losses.

I also ran some frequency response curves on the amp.  They are shown below.  Not bad for a mono Class D bass amp.

Here are my thoughts on the amp itself.  The box is a nice affair.  Foam keeps the amp safe, and a bag keeps it clean.  The box is way too flashy, but that helps when it is sitting on a card table at a flea market.

The amp has a nice layout, and is plenty clean.  Some items are a bit messy, but they are also cheap, so that is expected.

Here are the input MOSFETs used on the amp.  There are 10 in all, and each is rated for about 40A of current.  This all adds up to a very impressive power supply section. 

The transformer is the largest I have seen yet in a car audio amplifier.  It is very impressive.

The output transistors are rated for 200V, and can handle about 25A of current.  There are 6 in all.  This would be far too few for a typical Class A/B amplifier, but for a Class D it is more than needed to reach impressive output levels.

A single fan exists to cool the two inductors used in the output filter circuit.  This filter is important as it converts the pulsed amplifier output into a useful analog music signal.

The power inputs accept 4ga cable, and the speakers look to accept a max of 8ga.

The outside of the amp looks fine in my mind, aside from the cheesy logo, and the big block letters describing features and power.  Again this is typical flea market. 

So how did it do?

To test it, I invited a friend over who was into SPL, and had a suitable woofer for the task.  We used a Rockford Fosgate Power HX2 15 in a 6 cu ft box tuned to about 45Hz.  The woofer was wired for 1 ohm operation to the Vibe 1200D.  0ga wire was used from the battery to the amplifier.  A 1 farad capacitor also happened to be in the car, but it was not useful.

We played all sorts of test tones, and bass tracks.  The amp could maintain 46V into the woofer with sine waves, at low frequency.  The input voltage to the amp would drop as low as 10.8V.  46V of output is around 2000W into a 1 ohm load, as this was wired.  Now as most everyone knows, impedance changes with frequency.  My guess is the 1 ohm woofer was closer to 2 ohms for most its range.

I plan to get a AC current meter some time in the near future, so I can measure current and voltage, which is way more scientific than what I was doing.

Aside from that, the bottom line is this amp rocks.  It played very low, and nearly tore the car apart.  The bass was clean and clear.  One drawback was higher bass frequencies.  With these the woofer sounded awful, which it did not in the past.  Also with the higher frequencies, the voltage would drop to the 10.8V on the input.  My guess is the woofer is lower impedance at these frequencies, and therefore the amp has a hard time with it.

Stay tuned, as I plan to add more photos, and more info as I get it.  The amp is still in my friends car, and he is going to spend the week trying to kill it.