HarleyTechTalk

Technical Forums => Audio and Electronics => Topic started by: AAWAV on January 12, 2015, 10:24:55 PM

Title: 2 and 4 channel amp test results - multiple amps
Post by: AAWAV on January 12, 2015, 10:24:55 PM
Several of you might have read something about this.
a select group of guys have offered to provide me different amps for bench testing.

I would like to request to keep this thread "clean"... any comments, questions - I would suggest starting a new thread or reach out to me. Our moderator might make this a sticky... as Me, Gannicus, others and especially Nutz have had many many many of the same questions..."what amp"... "what speakers"...

DISCLAIMER:
BY NO MEANS ARE MY FINDINGS THE MOST ACCURATE YOU CAN FIND AS I DO NOT HAVE 3000 USD EQUIPMENT.

At least in my environment I am comparing Apples with Apples and I try to provide you with honest / non-biased information (I got nothing to gain here, I only "waste" time  :teeth: :teeth: . Glad to be able to help out fellow Harley owners that NEED to have a good sound system.

The RMS Wattage provided will be technically measured. The audio portion - as we all know - is subjective to the human ears (mine are not the greatest anymore  :smilep: :smilep: )

Highlights of the test result are posted in the thread - more details (usually 1-2 pages) in the document attached or accessible via the Dropbox link.



Title: Test NVX NVPA4 400W 4-Channel Amplifier (Class D)
Post by: AAWAV on January 12, 2015, 10:28:08 PM
Sponsor: Gannicus! Thanks Bud!

short results:

Input Voltage:14.3V DC (Motorcycle power while running; 10AWG power line, both + and Ground connected to the battery).
1 channel (FR) tested. Results below as shown on the oscilloscope.

2 Ohm load: 107 Watt (Vac ~14.6V)
4 Ohm load: 62 Watt (Vac ~15.6V)

This is above Claimed RMS power - but under a not to be mentioned online Vendor that certified the unit to be higher (keep in mind they use 3000 usd equipment - I use a 150 dollar O scope and high power resistors)

Amp supports bridging, but this has not been tested (basically the result should be around 215 Watts at 4 ohm – 2 channels as the output Vac will double).
During Audio sound test (4 channels), the sound was overall more or less neutral, with the perception of some lack of powering low frequencies.
Overall perception of loudness compared to my own amp on the bike (PA RZ4.2000D) is the RZ4 goes louder without distorting.
FM: seems to keep most if not all stations (I do not have the sweep on the bike anymore - just a piece of wire!)

More Details and pictures:
https://www.dropbox.com/s/iz2evvew8yuz49i/Test%20NVX%20NVPA4%20400W%204-channel%20amp.pdf?dl=0 (https://www.dropbox.com/s/iz2evvew8yuz49i/Test%20NVX%20NVPA4%20400W%204-channel%20amp.pdf?dl=0)

update: 1/13/2015: FM findings in the PDF document added
Title: Test PA RZ4-2000D 4-channel Amplifier (Class D) ~ SS PN4.520
Post by: AAWAV on January 12, 2015, 10:43:26 PM
Sponsor: ME! i took a beer for that  :smilep: :smilep:

This is just a short description - no document/details...

I have to correct my findings i posted 9 months or so ago on another forum... I was DEAD wrong... I did not run the bike at the test back then and the PA RZ4-2000D DOES react to input Voltage level (power!).

Results:

Input Voltage:14.3V DC (Motorcycle power while running; 10AWG power line, both + and Ground connected to the battery).
1 channel (FR) tested. Results below as shown on the oscilloscope.

2 Ohm load: 145 Watt
2 Ohm load: 102 Watt

This is way BELOW Claimed RMS power, but even any retard knows the PA claimed power of 250W at 2ohm is complete BS.
The PA RZ4-2000D is basically the SS PN4.520 and with that in mind, the 2 ohm RMS is ABOVE specs and 4 ohm dead on!
Using this amp you will most likely lose some or most or all FM radio stations (or even none; it is like flipping a coin).
I lost some...

fits in the Batwing.
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: dirtracin23 on January 13, 2015, 06:45:53 AM
WAV, Would it be possible to list input/output with bike off AND running. You know that many of us have set our gains with the bike off sitting in the garage, especially if doing it by ear, wouldn't they be off/wrong if there is a change in power numbers when the bike is running. If my thinking is flawed (definitely possible)  please explain.
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: UltraNutZ on January 13, 2015, 07:04:52 AM
your thinking is spot on   :up:


the numbers WILL vary with voltage changes.
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: AAWAV on January 13, 2015, 07:05:18 AM
I cannot recall whether or not I had to adjust the gains when running the bike after I dialed the amp in without running the bike (off: 12.2V input power)
I do have the #'s:
12.2Vdc input power:
4ohm: ~40Watt
2ohm: ~66Watt

so big difference.

amp is already gone but I will check this with the next one(s)
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: dirtracin23 on January 13, 2015, 07:33:56 AM
So then should gains all be set with the bike running to eliminate the possibility that the amp being installed is one of those in which the numbers running or off are different?
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: Little Mike on January 13, 2015, 09:01:23 AM
Quote from: dirtracin23 on January 13, 2015, 06:45:53 AM
WAV, Would it be possible to list input/output with bike off AND running. You know that many of us have set our gains with the bike off sitting in the garage, especially if doing it by ear, wouldn't they be off/wrong if there is a change in power numbers when the bike is running. If my thinking is flawed (definitely possible)  please explain.

Great, err frozen, minds must think alike. I posted this same question to AAWAV's testing post in another place.
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: AAWAV on January 13, 2015, 09:15:31 AM
As mentioned, I will test if there is a difference in gain settings with bike off and running and which one to use (lowest gains one to prevent "damage/clipping" in the "other' situation...
especially when using Low output (RCA) from the HU into the amp, it does not really matter as you should not dial in on the max HU volume (MY opinion... too many clicks up). So lets say the lower Gains are set with bike off and you ride your bike, you simply push the volume above the volume used to dial in... simple as that... and you will hear the distortion anyway.
if amp is too powerful for your speakers, you should not dial in to the max anyway, right! otherwise (Ka)Boom....

ps. I will report back around the weekend....
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: dirtracin23 on January 13, 2015, 01:51:08 PM
So, if I set my gains with the bike not running using NutZ DMM method I should be good either way?
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: UltraNutZ on January 13, 2015, 01:52:46 PM
you are correct.
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: speedzter on January 13, 2015, 02:21:23 PM
Can I ask how you determine the max power output ?
Are you basing it on visual clipping of the signal, measured
Distortion, or audible distortion ?
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: dirtracin23 on January 13, 2015, 04:40:15 PM
Quote from: UltraNutZ on January 13, 2015, 01:52:46 PM
you are correct.

Good.

This  :turd: has already made me cross eyed enough.   :teeth:
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: UltraNutZ on January 13, 2015, 04:55:07 PM
Quote from: speedzter on January 13, 2015, 02:21:23 PM
Can I ask how you determine the max power output ?
Are you basing it on visual clipping of the signal, measured
Distortion, or audible distortion ?

are you referring to me or one of the other guys?
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: speedzter on January 13, 2015, 06:00:56 PM
Quote from: UltraNutZ on January 13, 2015, 04:55:07 PM
Quote from: speedzter on January 13, 2015, 02:21:23 PM
Can I ask how you determine the max power output ?
Are you basing it on visual clipping of the signal, measured
Distortion, or audible distortion ?

are you referring to me or one of the other guys?

Sorry, I was asking AAWAV. 
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: AAWAV on January 13, 2015, 06:45:49 PM
Quote from: speedzter on January 13, 2015, 06:00:56 PM
Quote from: UltraNutZ on January 13, 2015, 04:55:07 PM
Quote from: speedzter on January 13, 2015, 02:21:23 PM
Can I ask how you determine the max power output ?
Are you basing it on visual clipping of the signal, measured
Distortion, or audible distortion ?

are you referring to me or one of the other guys?

Sorry, I was asking AAWAV.

Visual clipping of the sinus (as far as the human I can see) - so hence my "disclaimer" on the results not being as accurate as they could be... but then again I do not have $3000-xxxxx audio test equipment to get to that level of accuracy...
it is about are they up to spec or not (or over!) and how do they compare to each other
Title: Re: 2 and 4 channel amp test results - multiple amps
Post by: speedzter on January 14, 2015, 05:09:10 PM
No problems at all, that is how I allways used to do a quick power output check after building an Amp' .