# Massive Audio D800.4 - 4 Channel A/B Amp



## katodevin (Feb 14, 2008)

I recently had the pleasure of purchasing a Massive Audio D800.4 amp. I've been auditioning it for about 3 months both on the bench, as well in several cars. I thought I'd share my experiences with the amp, as Massive is proving to be a quiet underdog in the industry, and I feel that the quality of their product deserves a bit more attention.

*Aesthetics*
As much as all of us try and say that looks don't play a part in product selection, for 99% of the market, it does. I myself do care a look about the aesthetic design of the products I purchase, as I have a great appreciation for carefully thought out design. In my opinion, it often costs the same to produce a bad looking product, as it would have to produce a well thought out good looking one.

In this area, the Massive Audio D800.4 does not disappoint. 

This is one of the smallest amps I have used. Massive Audio is going to have to change their name, as the amp is anything BUT massive. It is freakishly small, competing directly with JL's new XD and HD line. It is a bit taller than the XD's, but will easily fit into many of the same areas. If I was an installer, I'd definitely be thankful for the footprint of the amp, as it opens up a ton of install location possibilities. Spare tire wells, underneath seats, small cubbies, passenger foot wells, no location is safe from this amp.

Other than the awesome size, I love it for its simplicity in design. It does not have any fancy flashing lights, skulls, airbrushing, etc. The D800.4 has nothing but clean and smooth lines. Upon powering the amp up, the Massive Audio logo in the center gently glows to let you know that it is operational. Nothing too bright, nothing flashing, it just simply glows to let you know everything is okay. 

Massive Audio is very confident in the efficiency of their optimized A/B design, and have excluded any fancy heatsinks and have opted to have a nice, clean chassis. At any point during testing, cooling was not an issue. 

*Design/Fit + Finish*
From the moment I picked up the amp, it instilled a good deal of confidence in the overall manufacturing quality. It is very heavy and dense, as Massive has packed a ton of components into a very small area. I am not sure if the aluminum is extruded or billet machined, but it has a nice brushed finish to it. The edges are clean and sharp and the amp arrived to me blemish free. Nothing feels cheap on the amp whatsoever.

The gain/crossover pots are all of good quality, as were the speaker/power terminals. I really enjoyed the detented pots, as they give a better tactile experience when making adjustments. There was no slop around any of the connectors. They seemed to be tied down to the chassis and board very securely.

On the surface of the amp there are several beefy hex head screws. These add to the overall industrial look of the amp, as well as serving as cosmetic covers for the mounting holes. Simply unscrew the corner hex head screws with the included allen wrench. This will expose the 4 mounting points of the amp. Mount the amp, using the screws or bolts of your choice, then screw the hex screws back on. Voila, seamless installation. No need to mess with amplifier feet or bottom mounting screws. This is a very elegant solution similar to what JL provides with their top of the line HD amplifier. I will also note that there are included wood screws for mounting purposes with the amplifier box. 

With many amps moving their connectors to a single side of the amplifier, I was a bit disappointed to see that this amp was still in the traditional power/speakers on one side, and RCA/gains on the other. Since the overall size of this amp is so small, I won't count this as a huge con, but it would be nice in the future to see Massive moving towards a single-side approach for all connections. This would open up even more possible install locations to everyone and provide JL even more competition in the small footprint/high power amp marketplace.

I experienced one hang-up during install in noticing that the RCA barrels seemed to not grip my RCAs as tightly as the other amps I was swapping in and out. My RCA cables would pull off of the amp without much effort, making me a bit nervous of an accidental disconnection during testing. This should not be a problem in a correct, mounted firm install. It seems that the RCAs on the amp are either a bit undersized, or too smooth to make a ultra tight connection. This was easily remedied by very slightly bending the barrel of my RCA cables to make tighter contact. Hopefully it will be addressed in future revisions. 

*Features*
All amp manufactures boast a plethora of features, ranging from flux capacitors to lithium ion fission generators. Many of these features are impossible to test/understand to the normal end user. I'll run through some of the features listed by Massive for their D800.4, focusing on the ones that I can tangibly identify and experience.

Filters - These are listed at 18db slope. The frequency response of both HPF and LPF is 50-750hz. The filters are able to be fully defeated by sliding the switch to "FULL".

While I would love to see a x1/x10 multiplier of the internal crossover, allowing for a more flexible crossover, there aren't many amps that include such a feature. The only ones that I've tested lately that have such flexibility have been the Zuki Eleets, and the Zed Audio Leviathan. The frequency response of 50-750hz is a bit limiting for the amp. The only scenario I see this crossover being useful is to push 4 sets of components, or 2 sets of components plus a small sub. Most users will not be using 4 sets of components, or trust "only" 240 bridged watts to push their sub, so these scenarios are a bit far-fetched. I feel that anyone running an active setup will use the internal crossover in "full" position. 

As for the choice of an 18db slope, I tend to prefer 12db slopes, as I personally feel that they allow for better integration between drivers. Some prefer 24db slopes since they like to run their drivers close to their useable frequencies and need the steep drop-off. Massive's choice of an 18db slope is a smart one, as it effectively provides the best of both worlds, and does provide good phase response, so the user doesn't have to worry about connecting speakers in/out of phase. I tested the functionality of the internal crossovers using an RTA on my test bench, and am happy to say that they perform the way they are advertised.

This all being said, this amplifier was tested by me using active setups, including a Pioneer DEH-p99rx, a JBL MS8, and a Pioneer DEH-p880rs. I suspect that many users looking for a high powered 4 channel amplifier will be running an active setup anyways, and won't be depending on the internal crossover. 

High Power Output
This amp is listed at 120x4 at 4 ohms. It has a good power supply which allows it to also make 240x4 at 2 ohms as well. I tested this amp pushing several power hungry woofers. I was able to audition the amplifier with Seas' ER18RNX (8 ohms), ID OEM V1s (4 ohms), and Exodus Audio's Anarchy midwoofers (8 ohms). I am happy to say that the amp delivered as advertised. It was able to push all of these woofers to very high effect, without displaying any signs of distortion or loss of control at high volumes. The speakers that I auditions are by no means efficient, and provided a very strenuous test for the power output of the amplifier. That being said, power ratings of amplifiers can most often be taken with a grain of salt, as some amps are rated rather optimistically, and others conservatively (Zuki @ 5 watts anyone?). I feel that a challenging test of power hungry woofers is the best indication of just how good an amp's power rating is in the real world, and The Massive D800.4 passed with flying colors.

Noise Rejection Circuit
This may sound pretty gimmicky, and if you had asked me about this a couple of years ago, I probably would have agreed. That is until I recently ran into an install where I used a very high quality amplifier that had garnered a lot of praise from all comers. It sounded great, but I could NOT get rid of electrical/alt noise no matter what I did. I finally gave up after checking all of the common answers like grounding points, RCA runs, etc, and simply swapped the amp out for a JL HD. This totally eliminated the noise. I changed absolutely nothing else. I was absolutely mystified and I bugged JL about the reason behind this. I found out that JL actually spends quite a bit of time engineering a noise rejection circuit, tying the grounds of the RCA's to the common ground properly, as well as other amplifier design practices that apparently work to reject noise, instead of cutting corners. 

Luckily, I still had access to the "problem" car, and installed the Massive Audio D800.4 into it. I am ecstatic to report that the D800.4 rejects noise just as well as the JL HD in this case. There is absolutely nothing worse spending hours of time chasing phantoms when the problem could have been solved with careful product selection.

*Usage Scenario*
Honda Accord Coupe 2008
Source - Pioneer deh-p99rx
Front Stage - Hybrid L1v2/Hybrid L3/Exodus Audio Anarchy
Subwoofer - SI BM MKIII

Fitment:
The small size of the amp provided tons of options. I tested it for fitment in a variety of unique locations:
Rear deck underside (where factory sub option would mount subwoofer)
Underneath passenger seat
Behind rear seats (you could probably fit 6 of them back there!)
Underneath front carpet in passenger footwell

If I were to use this amp in a brand spanking new install, I would most likely locate it on the bottom of the rear deck where the factory option subwoofer would go. It fits very nicely and could be easily mounted with bolts from the top of the deck, or with self tapping metal screws from the bottom. Wires could be cleanly run and you would give up 0% of your cargo space. I know that many of you like keeping rear fill. Using this amp to push 4 sets of components would be a very good choice and would get loud enough to make you cry.

If it was up to me, for maximum value, I would use this amp to push a set of components in the front doors and use it to push 2 x 6.5 inch subs on the rear deck. After spending some money on deadening, you would have a bad-ass system that would murder anything stock, premium or otherwise. The internal crossover points of this amp would allow this to be easily done, as you could easily pass frequencies of ~ 80hz and up to the components in the front doors, and frequencies 80hz and lower to your rear subs. Keeping the subwoofers on the rear deck would keep the trunk nice and clean so you could put your folding baby stroller, dead body, skis, penguins, wild tigers, etc into the trunk without a problem.

*Performance:*
I used the amp to push the 2 more power hungry drivers in my 3-way front stage - the woofer and mid. I felt that having the amp engage the least efficient drivers in the stage would be a good test of its power capabilities. Additionally, having the amp power the driver that handles the vast majority of sonic information (the midrange) would be an excellent test of its sonic characteristics.

The Exodus Audio Anarchy midwoofers are beasts. Just look up videos about them on YouTube. They can handle more power than I can imagine sending to them while sober, and they play ultra low without complaining. They recently tested very well on Zaph's test bench, and I sincerely believe that my doors would implode before I could push them into clipping. I have them crossed over at 63hz @ 18db up to 300hz @ 12db. The Hybrid L3's are known for their wide range, and are commonly used as "point source" speakers to play the majority of program material to ensure that the important imaging information is coming from a single location. These are crossed over at 400hz @ 12db to 4khz @ 12db.

The Massive Audio D800.4 performed very well. This was the first car that I tested it in, and it immediately brought a smile to my face. I normally run a JL HD 600/4 bridged to my Anarchy midwoofers, and the Massive D800.4 kept up admirably. When pushing them very hard with my volume set to the official "show off to my friends" setting, I noticed that the additional power from the JL amp kept things a tad clearer at the low end. I bumped the high pass filter slope to 24db, and the differences between the 2 amps disappeared. Right then I knew that the D800.4 was something special. It easily kept up with an amp costing much more, pushing more than 2x the power. I am sure if I used the D800.4 in the same bridged configuration only pushing my midwoofers, it would give up nothing to the JL.

In the midrange, there were no surprises. The D800.4 kept my L3's sounding as clear and beautiful as they usually do. The L3's are normally pushed by 2 channels of a JL HD 900/5. My imaging remained exactly the same despite the amp change, I suspect this could be a testament to the channel separation and frequency response. Very very nice.

*Conclusion*
I have extremely little to complain about this amp. The only cons that I have are:
Connectors are not on one side.
Crossovers do not run full range to infinity.
Not tight RCA barrels.

The pros of this amp run a huge list:
Small size allows for a huge range of install opportunities.
Simple industrial design looks and functions perfectly.
Powerful, transparent sound.
Detented pots for adjustment
Runs cool and efficient.
Lack of electrical noise.
Hidden mounting points.
Low noise floor.

I have always been of the mindset that the amplifier should simply amplify. Anything other than volume that is added to my system is undesirable. The Massive Audio D800.4 amplifies extremely well. I was very happy with the dynamics and headroom that it provided my test systems with. I think that many would be hard pressed to build a system that requires more power. Only things that would come to my mind would be 8 inch woofers in a door application, or pushing a monster dual voice coil sub. The sound remained clear and powerful way past normal listening levels in my test systems, and was uncolored throughout. 

The value of this amp is very high, especially at its current website price @ Massive. This kind of power out of such a small footprint usually commands a much higher price. This amp plays the middle pricing ground between the full-size amps and the new mini-amp breed that is attacking the market place. For installs in locations that are tight, or without much airflow, this is one of the cheapest and best options you can go with. The quality of sound and build are only the icing on the cake. It's been a pleasure testing this amp out and I'm already planning on using it in future installs.


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## katodevin (Feb 14, 2008)




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## JoeHemi57 (Mar 28, 2006)

Nice review, i've been checking out these and the nano series lately myself.


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## kvndoom (Nov 13, 2009)

> Noise Rejection Circuit
> This may sound pretty gimmicky, and if you had asked me about this a couple of years ago, I probably would have agreed. That is until I recently ran into an install where I used a very high quality amplifier that had garnered a lot of praise from all comers. It sounded great, but I could NOT get rid of electrical/alt noise no matter what I did. I finally gave up after checking all of the common answers like grounding points, RCA runs, etc, and simply swapped the amp out for a JL HD. This totally eliminated the noise. I changed absolutely nothing else. I was absolutely mystified and I bugged JL about the reason behind this. I found out that JL actually spends quite a bit of time engineering a noise rejection circuit, tying the grounds of the RCA's to the common ground properly, as well as other amplifier design practices that apparently work to reject noise, instead of cutting corners.


Ha ha, that's something I always tell people. You don't realize how important that is until you need it.

What puzzles me, is why an A/B amp would be marked _*D*_800.4 and have "Digital Block" stamped on the face. 

(not to mention that is is small. very VERY small)


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## katodevin (Feb 14, 2008)

kvndoom said:


> What puzzles me, is why an A/B amp would be marked _*D*_800.4 and have "Digital Block" stamped on the face.


Confuses me too. The explanation I got from them was that the other mono amps in this model series are Class D. My guess is that their Class D engineering isn't to the point where they can fit 4 channels into such a small chassis. If it keeps costs down, and is well designed, I don't see any disadvantage to getting an A/B amp in such a small chassis. I didn't notice any power issues such as overheating with the amp.


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## redcalimp5 (Sep 10, 2007)

Killer review! Seems like a sweet amp for the price. 

I've actually got a TRU 4 channel that I'm using to power my mids and my sub, and I can't seem to get rid of slight alternator whine. I've pretty much exhausted most/all of the basic steps most of us do, too, to no avail. I wonder if an amp swap would fix it.....although, I really don't want to get rid of my TRU. 

Thanks!


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## katodevin (Feb 14, 2008)

redcalimp5 said:


> I've actually got a TRU 4 channel that I'm using to power my mids and my sub, and I can't seem to get rid of slight alternator whine. I've pretty much exhausted most/all of the basic steps most of us do, too, to no avail. I wonder if an amp swap would fix it.....although, I really don't want to get rid of my TRU.


Yah, I didn't want to get rid of my trouble amp either, as it was simply awesome otherwise, but wanting to stab myself in the face while trying to fix the noise isn't cool either. I was never big on name brands - JL specifically, but the easy in which the HD solved my problems made me really believe in them a lot more.


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## show&go (Sep 25, 2010)

If you dont mind saying, what was the trouble amp?


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## Mahna Mahna (Mar 2, 2008)

What other amp would Massive be comparable to in terms of build quality and output?


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## mSaLL150 (Aug 14, 2008)

katodevin said:


> I recently had the pleasure of purchasing a Massive Audio D800.4 amp. I've been auditioning it for about 3 months both on the bench, as well in several cars.


So what were the results on the bench?


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## katodevin (Feb 14, 2008)

mSaLL150 said:


> So what were the results on the bench?


I had them hooked up to my reference speakers - the Zaph SR71 boxes. The amp did very well. I find that home audio - missing road noise, etc, requires much less power than in the car, so this was more of a test of tonality and noise floor. The Massive preserved the tonality of the recordings I threw at it, and had a minimal noise floor.


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## tRidiot (Jun 29, 2006)

mSaLL150 said:


> So what were the results on the bench?


I agree... I'd like to know some actual numbers, even to resistive loads at 12 or 14V?


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## robertigab (Jun 22, 2011)

Hi, 480rms x 2 @4ohm bridge with 40amp fuse????

test test!


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## Coppertone (Oct 4, 2011)

Thank you very much for such an insightful review. I have sooo many amps as it is now that I don't even bother to take them out of their boxes lol. I see that I am going to have to have a Christmas sale. Once again thank you for taking time out to do this for us. I for one really appreciate it.


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## kizz (Jun 22, 2009)

robertigab said:


> Hi, 480rms x 2 @4ohm bridge with 40amp fuse????
> 
> test test!


According to Massive Audio's website it's 480rms @4ohm. If that's true sign me up!!!


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## chford (Jul 8, 2011)

That is one serious review for an, apparently, serious Amp. Thanks!


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## ZAKOH (Nov 26, 2010)

kizz said:


> According to Massive Audio's website it's 480rms @4ohm. If that's true sign me up!!!


The poster is implying that it is unlikely that the amplifier provides the rated power given the 40amp fuse. I would agree. I will not believe Massive Audio's RMS wattage unless confirmed with independent test. Seems like they like inflating the numbers.


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## Brian Steele (Jun 1, 2007)

ZAKOH said:


> The poster is implying that it is unlikely that the amplifier provides the rated power given the 40amp fuse. I would agree. I will not believe Massive Audio's RMS wattage unless confirmed with independent test. Seems like they like inflating the numbers.


What's the CEA 2006 rating? Is one quoted?

It's a bit difficult to believe that something that size can meet the quoted specs and be a class AB amplifier to boot. I'd be tempted to pop it open and have a look at the innards.


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## Hdale85 (Jan 21, 2012)

Curious if anyone has bridged one of these and ran it a bit below 4 ohms? I'm going to be running a 3 way active front stage with a JBL W10GTi MKII sub and it runs at 3 ohms, I'd like to use 2 D800.4's to run all these so wondering if it'd have a hard time with the 3 ohm load. I know they don't rate it at 3 ohms and I know the specs don't go below 4ohms but just curious if anyone has tried.


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