NVX MVP4A Micro Amplifier

[Beckerson1]

Alright this is the second go around with this review guys. Had the other one 90% done and this idiot hit the refresh button for some odd reason.

Anyway I've been looking into getting a different amplifier for my garage setup. After some looking around I came across the NVX Micro amp and thought that would work really good in a garage setup (small size was a big selling point). Now you may have seen that these small amps did quite well on a Amp dyno:

+ YouTube Video

Here are some specs:

4 Ohms Rated @ 14.4V = 50Wrms

Bridged 4 Ohm stable @ 14.4V = 175Wrms

2 Ohms Rated @ 14.4V = 100Wrms


Speaker level input as well as RCA


Alright I'm going to go off on a little tangent here as its something I need to mention. I purchased my amp in Brand new condition (you expect it to look brand new). As I open up the package I remove the two layers of plastic and this is what I'm welcomed with (please note that these two layers of plastic are fairly thick so there is NO way this could have happened after the plastic was on):



Now as you can see there are a couple deep gashes and then there are a lot of micro scratches all over the face. Now to me when one sells something as brand new I expect it to look brand new. Now I am contacting Sonic about this to see if they will refund a portion of the total cost for a NEW unit clearly being a scratch and dent item. Other then this the amp is 100% functional.


Now back on track. Here are some gut shots

In this pic once you remove the rear cover you will notice this. There are two contact points on the rear cover which contact the two points indicated with the thermal paste. This acts as a heatsink for these two pieces



Now what you can't see to well (I need to figure out how to broaden the focus area on the camera) is they do use solder as a bridge on a couple components. Now this could be a issue in the future for vibration resistance.

Now once you remove the screws holding the board to the case you get this:



Overall a very clean layout. Now this is probably isolated to my unit but if you look at the red/black wiring coming off the transformer they were preventing the (can't recall the name, let me know if you do and I will edit it in) heatsink mount from contacting this particular unit. Could cause overheating issues and potentially failure. Now I suggest that anyone who gets these amps open them up and check to make sure things are not preventing proper cooling.

Now lets move onto the Speaker terminals:



Now you may ask why I'm posting this (first off its not the nasty white looking crap on the plastic, it's not anywhere that visible). I will tell you this. You better use small wiring as you won't be getting anything over 16 gauge in there without modifying spade connectors. Plus these are counter sunk slightly so its not the easiest to work with. Something I'd be willing to sacrifice added size for proper sized terminals for regular spade terminals.

Now here is another thing that was messed up when I opened up the unit. The longer pad was half way off its mount. Now I could only assume these are thermal pads to help transfer heat to the heatsink:



Here are the two hard mount points for those two pieces I talked about above:



As you can see the one clearly wasn't contacting due to the wires. That is now fixed.



Now this is as far as I am on this guy. I still have to get it into the garage and I will then do some extended play on the amp. I will go into more detail later on.

[97_eldo]

nice little unit there. too bad about the scratches and internal issues....minor but a pita none the less.
probably a good thing that you caught the heatsink issue.
thanx for taking the time to write up the review
and thanx for sharing

[Beckerson1]

Originally Posted by 97_eldo

nice little unit there. too bad about the scratches and internal issues....minor but a pita none the less.
probably a good thing that you caught the heatsink issue.
thanx for taking the time to write up the review
and thanx for sharing

Ya no problem. Plexi can be resurfaced and the internal issue was a super simple fix just moved the Wire out of the way.

Long term use will determine if heat issues show up. Overall a good little unit.

[southerntrendkill]

Actually I would be dissatisfied with the QC on the NVX product of I was you to be honest I'd prolly return it. But Idk if it's just me but I expect my products to look as well as they perform that's not to say that lil amp doesn't perform great cuz it may but again I would be disappointed.. great review

[Beckerson1]

Originally Posted by southerntrendkill

Actually I would be dissatisfied with the QC on the NVX product of I was you to be honest I'd prolly return it. But Idk if it's just me but I expect my products to look as well as they perform that's not to say that lil amp doesn't perform great cuz it may but again I would be disappointed.. great review

Don't get me wrong I am upset and they will hear about it. As to what happens is unknown. Unfortunately for me I CAN'T prove the amp arrived in this condition as I did not document the un-wrapping of the amp. Not that I could tell it was damaged with the plastic on anyway.

If it were something I'd be showcasing outright I would return it. But as I said its fully 100% functional and going into a location where 1) not many will see it, 2) looks don't fully matter, 3) simple cosmetic fix if I should pursue that option

[southerntrendkill]

I agree it's just you know how we are when we finally decide on another audio product and wait for it in the mail like a kid waiting for Xmas and then u rip it open to see stuff like that. But I agree not worth the hassle if it works perfect and isn't gonna be displayed in a car or something.

[Beckerson1]

Originally Posted by southerntrendkill

I agree it's just you know how we are when we finally decide on another audio product and wait for it in the mail like a kid waiting for Xmas and then u rip it open to see stuff like that. But I agree not worth the hassle if it works perfect and isn't gonna be displayed in a car or something.

Ya it's going to be used in the garage and for portable test benching and when the time comes I'm going to sell her off to my bro (has a truck and space is limited. Perfect match

[matt.u]

i like this little amp but i think i would rather buy another stetsom vs400.4 and they are a little cheaper.
Stetsom VS400 4 Mini 2 Ohms 4 Channel Car Audio Amplifier New Version Mini | eBay

Stetsom Vision Series VS400 4 4 Channel 400 Watt RMS Mini Car Audio Amplifier | eBay

[southerntrendkill]

They ever reimburse u any money for the damages???

[Beckerson1]

Originally Posted by southerntrendkill

They ever reimburse u any money for the damages???

I'm messaging them now. I'm not pushing for reimbursement but will see what they say about it. It's a super simple fix as I have the stuff to make it look brand new without the scratches. It's my judgment call there but I did make it known they as a company are sending out units that shouldn't be going out. Some people won't be as nice as I am.

[97_eldo]

Originally Posted by Beckerson1

I'm messaging them now. I'm not pushing for reimbursement but will see what they say about it. It's a super simple fix as I have the stuff to make it look brand new without the scratches. It's my judgment call there but I did make it known they as a company are sending out units that shouldn't be going out. Some people won't be as nice as I am.

^ x2

[Beckerson1]

I've talked with Sonic about this issue and they offered to replace the unit (no charge to me) but I decided to forgo that and seek for a reimbursement against the price of the unit. They ended up taking 10% off the price and putting that towards store credit. Which is fine with me as I'm sure there will be something I will use it on.

With the holidays it did take some time to resolve this but it was done in a timely manor. Didn't have to wait on them at all and the person I talked to was appreciative and glad to hear some feedback.

Now as to if they will mention something to the manufacture I can't say but I did what I could.


I was going to install the unit while I've been off for vacation but got the bug and am currently hacking up a lung so haven't had the time to install it.

[southerntrendkill]

Dude it's safe to say you already have bronchitis..

[Beckerson1]

Originally Posted by southerntrendkill

Dude it's safe to say you already have bronchitis..

Ya. My voice is going due to the cough. Which is bad cause Friday when I go back to work I have to be able to answer the phone. If not I will have to take a couple more days of emergency vacation. Just until I can talk again


Went to the doc but he said there isn't much he could do at that point in time (I wasn't coughing up anything, dry and he said my lungs sounded fine). Said take OTC medicine.

Now after a couple days its still fairly dry but do cough up some stuff. If by Friday nothing improves I will go back to my doc.

I've got Mucinex DM. Should be taking that. That crap makes me so Dry its not funny. Gave me a bloody nose the other night

[southerntrendkill]

Tell your doc to give you tussinex mmmmm it will stop your cough and as bonus will make you want to sit in your room with a black light on listening to comfortably numb if ya catch my drift

[Beckerson1]

Originally Posted by southerntrendkill

Tell your doc to give you tussinex mmmmm it will stop your cough and as bonus will make you want to sit in your room with a black light on listening to comfortably numb if ya catch my drift

lol i could only imagine

[blackdragonx1186]

I used to have to talk on the phone. Original Ricola works pretty damn well to help sooth it enough to talk.

[Beckerson1]

Originally Posted by blackdragonx1186

I used to have to talk on the phone. Original Ricola works pretty damn well to help sooth it enough to talk.

Ya I'm not to bad today so I'm giving her a shot. I only have to work tonight and I don't work tomorrow so I just hope I don't have to be outside for very long tonight. That's something I probably shouldn't be doing right now.

Ya I like Ricola brand.

[Beckerson1]

Update:

So I really hate the small speaker terminals on this amp. You'd be lucky to fit anything more then 18 gauge and still keeping it clean. Even if you try to use spade terminals you'd have to modify them to fit. I still stick by my original post saying I wish they would have added a inch or so to the width so these terminals would be of more sensible size.

[southerntrendkill]

18ga at the biggest!!! Wtf

[Beckerson1]

Originally Posted by southerntrendkill

18ga at the biggest!!! Wtf

You probably could fit 16 but I'm using 12 gauge from my speaker leads and it won't work.

Major downfall of the amp itself.

[southerntrendkill]

So how's this little sucker holding up for ya? You been using it frequently enough to comment on that

[Beckerson1]

Originally Posted by southerntrendkill

So how's this little sucker holding up for ya? You been using it frequently enough to comment on that

I haven't. Been to cold to test it out in the garage. I'm selling my Planet Audio p704 which is in my room and will test the NVX with my tritium kit. Bridged at 8 ohms. Even non bridged it pushed the speakers with ease. I will wire it up tonight.

[Beckerson1]

Alright I wanted to post up some initial listening tests I've done on this amp.

Source unit:

Laptop

Soundcard:

USB 7.1 soundcard using 2.1 config (for now I've bought a MiniDSP 2 x 4 for this setup so will be a very nice upgrade just for the EQ alone)

Speakers:

Tritrix Kit (8 ohms)

Anarchy Horn (x2) (8 ohms each) wired to 4 ohm


First off I started with the normal 2 channel setup (non bridged) and set gain by ear using HPF on the amp to limit 40hz down. My initial impressions weren't all that great. First off I couldn't get all that much output before the amp clipped quite bad and even though for the size of the room it was plenty loud BUT lacked as far as Overhead type sound. Wasn't as alive.

So at this point I added in my two Anarchy Horns (wired to 4 ohms) and bridged this output. Left me wanting more power for the drivers. I will say this now that unless your substage is only a 100W or so I'd suggest a dedicated amp as this (will push it) will leave you wanting more. Once again the overhead just isn't there for a sub IMO

Next I decided to give the amp another chance on the speakers so I bridged the tritrix kit and there was significant improvement as far as the liveliness of the songs. The overhead was greatly appreciated



Ok so the overview:

I will tell you this now. If you plan to use this amp for a sub, unless its a very low power sub you will be left wanting more and I suggest trying the Mono micro amp as that should provide enough power with overhead for some of the low power subs out there (200Wrms @ 4 ohm and 300Wrms @ 2 ohm)

Strictly used as a Highs amp I feel for most 100W speakers (4 ohm/8 ohm) out there will do great with this amp. You get what you pay for and I wouldn't say this is the best Micro amp out there but as a entry level amp for simple aftermarket integration in the same footprint of some of the bigger amps out there this is definitely a good performer. I'd compare it to be the Hifonics amps of the micro world. Good budget friendly amps that do rated. I do hope eventually they do a revision to this amp to improve the size of the speaker outputs on this amp. Just WAY to small and hard to make look clean. I'd be more then willing to lose a inch of width to utilize standard size terminals