Monday, March 2, 2015

Infinity Primus p163 measurements and comparisons.

Infinity Primus p163

The Infinity Primus line of speakers has been long standing go to choice for those looking to put together a solid home theater or music set up. The Primus p163 specifically, is very commonly suggested as good choice for the front two or three speakers for the those looking to build a nice entry level home theater. Overall the combination of positive technical reviews and a happy user base continue to make these a popular choice.

I have personally used the entire line, minus the p252 and the matching subwoofers. Overall I have been very pleased with their performance to price ratio and prefer the Infinity's to other common budget values like the Pioneer BS22 and Micca MB42x

Previously I've reviewed the Infinity Primus p143 and thought that they were great performers for the price and should be an option for everyone looking for a sub $100 set of bookshelf speakers.

First let's look at two professional measurements of the Primus p162

In 2007, Stereophile did comprehensive review of the Primus p162 and provided theses measurements.

SoundStage! Network created these measurements of the p162 in an actual anechoic chamber.

In a quick comparison of the two measurements were can see that they match up very well. There are some obvious differences though. The low end from about 60hz to 200hz is measured as a bit more inflated in the Stereophile measurements, my guess would be probably due to the close mic measurements taken, and the large spike at 700hz (due to some nastiness out of the port) is softened a bit. But overall you can tell they are measuring the same speaker and getting very similar results. 

Here are my measurements of the Infinity Primus p163

These measurements were all taken outside, at 1m distance.

After 500hz, my outdoor measurements match up very well with both the Stereophile and the SoundStage Network. I was not able to do close mic measurements on the Primus p163, so unfortunately I can't compare the mid and port measurements to Stereophile or NoAudiophile, though I trust that their near mic responses are accurate. Equally unfortunate is the floor reflections that affect the measurements before 500hz. However, the Primus still remains very close to +/- 3db throughout

The green trace is what I wanted to highlight the most here and what shows show adjusting placement a little bit in relation to the seating position can really bring out the best in the Primus p163. By raising the tweeter to just ABOVE ear level, much of the elevated tweeter response is diminished and made for a measured response of +/- 2db or less for 800hz until the tweeter begins it's steep drop off after 16khz. While the extension might not be as great as other speakers, I'm very impressed with the flat measurements.

Next are some comparisons to popular reviewer NoAudiophile

strategicdeceiver AKA NoAudiophile, has also recently taken detailed measurements and made an EQ correction file to address some of the response issues and mellow the tweeter direct on axis response.
When the review came out, I was initially a bit skeptical because the measurements were so different in regards to the p143's tweeter output at 7khz and above, as the use the same driver. The cross overs look very different, p143 vs p163, but I lack the knowledge to understand the results of those differences. Perhaps some tweeter attenuation is designed into the p143. When I began my own more detailed look at the p163 I was able to confirm very similar tweeter measurements.

Grills on

Grills off

EQ corrected response vs Speaker raised 2 inches

In my measurements, by raising the speakers just a few inches in relation to your ears (mic position) you could achieve results very similar to those of the EQ file does.

I have not used the EQ files and have since moved houses; so I probably wont be able to recreate the exact some 1m responses, instead will have to make new ones which will have their own possible issues. But I don't disagree with any of the EQ aspects. I do think his listening impressions are very colored and don't accurately represent the impressions that many others do due the obvious room issues in his testing workshop.

I personally like the Infinity line more than the Pioneer Andrew Jones. I think they are better speakers, I find the Pioneers to be too warm and even a bit muddy. At full retail price, I do not think the Infinity Primus p163 represent all that great of a value when you have some very exciting bookshelf options just under $200. I also don't know of anyone buying them at full retail either. I would suggest to those looking at the p163, to move up to the Infinity Primus p363 Tower and wait to pick them on when they are on sale for $99 each. You'll save on the need for speaker stands, and they have been very well reviewed and do not seem to have the same elevated treble after 7khz


Overall I like Infinity Primus line a lot. I think the p143 is one of the best tiny speakers you can find. The rest of the Primus line has a large following behind then, and when on sale, I don't think anything new in the same price can beat them. I would avoid being right in line with the tweeter, get a little below them if possible to mellow them out. If you can't do that, then use the EQ file made by NoAudiophile. But if you are still looking at the Primus line, a better idea would be to jump up to the p363 towers.

Monday, January 12, 2015

Insignia NS-SP213, Best Buy did something right... and cheap

Insignia NS-SP213 Best Buy did something right... and cheap

For the most part all of us who review cheap speakers have been sticking to products you can buy on Amazon. I left that comfort zone and went outside, drove to the dreaded Best Buy and picked up a pair of their cheap bookshelf speakers, the Insignia NS-SP213. The previous generation of Insignia bookshelf speakers, the NS-B2111, got a good amount of fan fair for a being a cheap bookshelf speaker during a time before the Dayton B652's or anyone looking at $100 speakers ever heard of Andrew Jones.

So was Best Buy successful in producing a good sub $100 speakers? I think so. In fact at the retail price of $69.99 and a sale price of $49.99 they are tough to beat.

Detailed album of Speaker Disassembly pictures.

The NS-SP231 are your basic black cabinet speaker. At its retail price, there really isn't a huge number of options; and they all are black. But this is easily the prettiest of the bunch. Not shown is the keyhole mount to hang them on a wall.

With Grill

Without Grill

Here is it, next to the Dayton B652

Taking apart the speaker to inspect the drivers and construction proved a little more interesting than expected.

What kind of sorcery is this?

Basic black stamped basket midrange driver

But! A nice, real crossover. No full range mid and cap on the tweeter. The only other speaker in this price range that has something like this would be the Micca MB42x's at $79.99. I also like the molex plug on the tweeter, made my life a little easier while testing.

Tiny bit of corner bracing on the front baffle, and the smiley face port.

Figured out why my screw driver stood up on it's own. Dat magnet.

For the money, this is a well made speaker. Much better put together than many of the units it would be competing against (Dayton, Polk, Monoprice), and not far behind the Pioneer BS-22's or Infinity p153's. Certainly better than the much more expensive and beloved TEAC LS-H265.

So how did it all sound? Pretty damn good for the most part.  

Insignia NS-SP213 Frequency Response Graphs

Here are the individual driver frequency responses

It looks like the drivers are crossed over at about 2.5khz. I didn't find any official documentation that listed it.

Grills are a killer on these things and just make the treble all manners of wonky (as seen in multiple measurements in the album). I recommend taking them off. The speaker is good looking enough that the drivers don't need to be hidden.

Port looks to be tuned around 80hz, so these wont be bass monsters.

Now for the important par; the 1 meter measurements.

As seen in most of my indoor measurements the hump at 150hz is present. The midrange might be just a touch thin, but never bloated or too forward.

Aside from the dip at 350hz, this speaker is +/- 3 db form 150hz (which matched the roll off of the close mic measurement) to 18khz when measured outdoors. And measured pretty similar indoors until about 400hz where room modes get more active.

When measured @1m outdoors the port doesn't seem to be outputting much volume.

Compared to some of the other speakers in the segment, the Insignia's compare with very well. I found them to be very similar to the TEAC LS-H265 in over all tonality; however they do lack the good bass response of the TEAC's. The TEAC's best the Insignia overall, but at 3x the cost.

Unfortunately I've seemed to have lost my .mdat file with the TEAC's outdoor response so I can't overlap them until I get a chance to measure them again. But here is the original TEAC measurements for comparison.

The Insignia's are far and away better than any of the Polk budget offerings (R15,R150 and T15). Much better than the terrible Dayton B452, and lack the harshness that can be heard in the happy accident of the Dayton B652's. I don't have better measurements of the Sony SS-1000, but I'd be welling to bet the Insignia's best those also, the Sony's were very muted with in the upper registers.

I know, call me crazy and stupid, from a personal enjoyment stand point, I liked them more than the Pioneer BS22's, but I personally find the BS22's to be too warm for my taste, and slightly muddy in the bass.

With the understanding that the Insignia's weak bass output points to them needing to be paired with a subwoofer, I would pick them over the Pioneers for myself.


Don't count out the Insignia NS-SP213 just because it's cheap and found at a mass market consumer electronic store. It's a good speaker that everyone shopping this price point should look into. The fact that they can be found locally for many people and have an easy return policy should be an added bonus. Without a doubt they would make an excellent surround speaker.

Monday, December 22, 2014

Polk R150 Review: Silly looking R15 and T15 clone?

Polk R150 Review: Silly looking R15 and T15 clone?

One of my first reviews was of the PolkT15, a simple bookshelf speaker found on sale at Best Buy for $49.99. From all the information I can gather; the T15 and the R15 use the same drivers and crossovers, however the T15 is front ported and R15 is rear ported. So those differences made little bit of sense from a users point of view. 

This brings us to the Polk R150, kind of an oddball bookshelf speaker. With it's tweeter placed below the mid (but nothing indicative of this being for any technical benefit). I can only imagine that this bookshelf along with it's sister speakers, exist only to be sold as door buster items. From what I can tell, none of these speakers are currently found listed on Polk's product pages as it is.

I went in to this review with the idea that the R150 probably is just the T/R15 flipped upside down, and missing any sort of wall hanger built in if you were looking for that. Between the two, I though the T15 was a better looking speaker, it's easier on the eyes but over all construction quality seems to be about equal. It's when I took apart the R150 that it was confirmed that they share at least the exact mid-range (they all have r15 printed on them. And while the tweeter on the R150 didn't have R15 printed on it like the T15 did, it's of the exact same size and visually identical. Seeing all this, I have to assume that they are nearly identical speakers (though I do hope to get new close mic and 1m measurements of the T15 soon)

Listening was done in different rooms and it has been a long while since I spent any time with the T15s. I did find the bass response very lacking, with the sister speaker the T15 to be slightly superior, I think due to the front firing port. Overall the R150 sound remarkably similar (the same?) to the T15's from the mid-range and up. By far the biggest issue is with vocal reproduction. In everything I listened to they just seem layered on top everything else, and not in a good way. But like vocals were cut out of construction paper and glued over the music playing behind them. It is very distracting when you hear it. The cheap tweeters are just not very articulate and with the significant boost after 10khz (see measurements) that are pretty fatiguing.

While music reproduction is not these speakers strong point, I could see them being used in a more home theater like situation where the ability to hear vocals may take priority. However their remain options that would do both better.

Unless you need some Polk bookshelf's to use as surround speakers, I would look into many of the other offerings at similar price points.

Disassembly Pictures

Above is a album of the speaker and it's components. It's as well made as any of the other $50 bookshelf speakers. At it's "retail" price, other offerings are both better performers and better built, the Pioneer BS22 and Infinity Primus options are easy step ups. If you are reeeaaaallly looking to stay in the sub $50 a pair price point, it remains hard to beat the Dayton B652 AIR.

Measurement Album

Close mic driver measurements

@1 meter

Above are the measurements I took. Both the close mic-ing of individual drivers and single speaker 1 meter responses indoors and outdoors.

From the individual driver measurements, we can tell that the mid-range doesn’t have very good lower extension. It really taps out at 100hz, where it takes a very steep nose dive. In theory, I guess the ports output could help make up for that steep fall off, as my measurements give it good output to about 40hz, though I highly doubt you would get close to that in an actual listening environment. The mid gets a little ugly between 1khz and 3khz, where it's crossover point. Tweeter measurements with and without the grills are pretty similar. At least the grills don't kill them like they do on the Pioneer BS22. However their output rises quickly and large peak after 10khz.

In my 1 meter measurements many of these issues can be seen manifested to various degrees. With the in room measurements, the Polk R150 shares the common bump from 100-200hz that rear ported speakers show in my room. Just as in the close mic measurements, the ugliness 1khz-3khz can be seen and is even more problematic thanks to it also being in the middle of a 10db hump. This is where I think much of the problem lies. It doesn't help that there also exists a pretty good size valley after it that then grows in the a nasty spike at from 9-16khz. These is one situation that presented it self in both the T15 and R150 regardless of measuring techniques. I think it shows that something it fundamentally wrong with the speaker.

Overall, this is another speaker to avoid.


The upside down version of the R15 and T15. Not very musical, sound bad and Polk should feel bad. If you are only going to spend $50, get the Dayton B652 AIR. The R150 might be ok if you really need a cheap Polk surround speaker.

Wednesday, November 12, 2014

The new Dayton Audio B452: Disassembly and on axis frequency response graphs.

The new Dayton Audio B452: Disassembly and on axis frequency response graphs. 

The Dayton Audio B652 has been one of the go to ultra budget bookshelf speakers. It is not a perfect speaker by any stretch, but wt it's price point it is hard is near impossible to beat. And for those looking for 2.0 set up that beats a sound bar or desktop PC speakers; it fits those requirements pretty well.

Dayton has been pretty active over the recent months with the release of the B652 Air, the T652 Tower speakers, and these smaller B452 bookshelf speakers I am writing about now.

So how do these smaller, B452 bookshelf speakers compare to their older and larger sibling? Well I have not been able to do a real sit down and AB listening test. Time has not been on my side and the left channel on my AudioSource Amp One is beginning to go out on me. So at this time the best I can do it some measurements and disassemble pictures.

Overall fit and finish matches the rest of the current Dayton offerings just fine. However there was one new addition to the B452 that was rather interesting. That is the addition of a slightly more complex crossover. Now, I don't know anything about crossover design, but this new one includes a resistor in addition to single capacitor. So some different sort of black magic is happening.

After giving these some time to break in, the first thing I noticed is that there are really inefficient speakers. You will have to crank the volume pretty high to get much usable output. After giving them a through listen, it's that usable output that is a problem.

To make it short, these are bad. Like really really bad. Dayton should not be proud of these. It's hard to imagine these being used by anyone. If you need small speaker with a 4 inch driver, go straight to the Infinity Primus p143, if you can't find those, the Micca MB42x will probably be a good choice.

Comparing the Dayton B452 to the Teac LS-H265 just isn't fair, Granted that Teac's are now about 5x the price of the Dayton's, but the Teac's are one of the great examples of budget options out there.

Album of Dayton Audio B452 disassembly

Album of Dayton B452 and B652 close mic driver graphs & 1m

So what can we gather about the new B452? Let's take a look at the graphs and see.

Dayton B652 and B452 outdoors @1 meter

Top = B652, Bottom = B452

There is a very large difference in speaker efficiency here. 84 dB 1W/1m for the B462 vs 87 dB 1W/1m for the B652.You can see that these two speakers share very little similarities after 1.5khz. The B452 begins it's drop off in output as early as 150hz.

Where as the B652 has hits awful cone break up at 4lkz, the B452 has a large dip in the response between  ~1.5khz and 5khz. This is also very clearly seen in the individual driver graphs that follow.

Dayton B652 and B452 outdoors close mic

From these graphs we can see that the mid plays relatively flat from 100hz to ~1.5khz (I know nothing about cross over design, but the B452 introduces a resistor into the mix, instead of the B652's single capacitor on the tweeter)

But is that early and step decrease in output on the mid and fact that the tweeter doesn't gain any real steam until 5khz that seems to have causes the significant dip between  ~1.5khz and 5khz as seen in the 1m graphs.

The cone break up appears to be pushed higher up into the 5-6khz range.

That tweeter also seems to be spiting some fire after 10khz. The tweeters in the B452 look the same as the tweeters in the B652 but at least via measurements, the sure don't seem to perform the same. Something is different.

Dayton B652 outdoors close mic

Seen above is the same type of measurement done for the B652, There were done at the some time as the B452 just to eliminate as many variables as possible.


These speakers are bad and Dayton should feel bad. Spend your money on Keystone Light instead. 

Friday, October 24, 2014

Teac LS-H265: The latest new hotness cheap speaker on the internet. First impressions and measurements

So I jumped on the internet bandwagon and picked up a pair of these Teac LS-H265B's for $90. I must have gotten in early because they are currently just above $160 on amazon.

I did some very preliminary listening and took some measurements of the speaker. Overall, it seems like a good buy at about $100. The close mic measurements and even the in room measurements are very good.

Album of speaker boxing, disassembly, driver and box details.

Here are the quick measurements. These are right out of the box and look pretty good.

Looks like the port is tuned to 60hz and at the mid and tweeter are crossed over at 2.5khz. 

Overall really flat (+/- 3db) from 700hz to ~15k where there is a steep and sudden drop off. Everthing below that is probably due to some room issue. With my common hump ~150hz, but it is actually pretty marginal and only really there because of the slight dip from 200hz to 600hz. Those these are lacking in the bass department, with a fast drop off at 100 hz. These will need a sub or at least some rear wall. (UPDATE: In retrospect after seeing the outdoor measurements, I'm not sure that the TEAC's are as deficient in bass response as I initially though, I do think the driver has broken in a little with additional use, and the in room bump from 100-200hz may have made seem to produce less bass than they actually do. However I would still recommend a subwoofer to be used with this or have placement a bit closer to a rear wall than my testing location allows.)

Above are some comparisons between the indoor and outdoor responses. Very similar results above 800hz in both situations. Outdoors and away from reflection, these speakers measure pretty darn good. with a slight rise in output as you get above 4khz. Even indoors, it wouldn't be hard to EQ down my 100hz-200hz hump.

A 15 minutes listening session AB testing the Teac LS-H265 vs the Pioneer BS22, I found that the Pioneers sounded much warmer, and had a little bit better bass extension. I haven't yet done a detailed test of the Pioneers to get comparison graphs going on, but I would  guess that their tweeter is a little less bright also. (measurements have shown the grills are a huge killer on the Pioneers)

The Teac's to lack in the bass department and should be pair with a sub, particularity if they are not going to be near a back wall. The more I listen to the Teac's the more the bass has developed and I think for many people and types of music they will be just fine as far as bookshelf speakers go. But they are very clear and articulate speakers and I enjoy them very much. At $100 they are exactly what budget audiophile should be looking for. However with their recent popularity, prices have gone up into the $160 range. The biggest disappointment was their construction quality, for something with a retail price of $250 they are not built nearly as well as many of the other go to budget speaker out there.


If these are in your budget and you like the high gloss black finish, you can't go wrong with the Teac LS-H265.

Thursday, October 23, 2014

My experience with the Definitive Technology Studiomonitor 45/65's. Measurements and short Review

My experience with the Definitive Technology Studiomonitor 45/65's. Measurements and short Review

A while ago I did a comparison between the Pinnacle DB 500 and the previous generation Definitive Technology Studiomonitor 350's. I found both to be very enjoyable but the SM 350s suited my tastes more and thus kept a place on my shelf.

When I got the opportunity to buy these new generation Studiomonitors at an insanely cheap price thanks to a lazy Best Buy employee, I couldn't pass them up ($150 for the pair). They immediately went to use in a 2.1 home theater system. I quickly added 3 Studiomonitor 65's as my front 3 and moved the 45's to the rear. In this application they worked well enough, but I always had this sense that they were a little dull; they didn't seem to live up to the reviews, and I kept wanting to go back to the previous generation Def Techs.

So after a while, and after switching to a Pinnacle (BD 650 II/700 II) front 3, I started to focus on the Def Techs as music only speakers, I had such a good experience with the 350's I thought that the 45s and 65's would be amazing. Unfortunately things immediately sounded off, just muddy,dull, lifeless. All those adjectives that someone would use when they are not impressed by a speaker. Many ABX tests with other speakers and a few dozen attempts at in room measurements, I just couldn't figure out why there is such a disparity between my experience with them and all the other positive reviews on the web. I still don't know what in my room that has contributed so greatly to my issues with these speakers and not others.

While the Definitive Technology SM 45 and 65's don't sound or graph all that well in my room, my close mic measurements were nearly identical to what Stereophile produced. So I do not have the ability to say these are bad speakers, only that they didn't work in my situation and it's been a great lesson in trying to listen before you buy.

Album of pictures of speaker and drivers
Album of Graphs

Each graph has two measurements on it. RED is the outdoor close mic measurements, BLUE is the indoor close mic measurements WITH any other driver unplugged. So during the tweeter measurement, the midrange is unplugged and vice versa.

All Driver Measurements @ 1 inch. No smoothing


Port look to be tuned to 45hz. Something loud and ugly is happening between 700hz and 900hz. Not sure of the cause to that, but it is seen again during the midrange response.

Drivers have a steep fall off @ 80hz and crashes to 50hz where there is another bump @ 35hz. Looks like a rather shallow xover at ~2.2khz


Similar shallow xover. Pretty smooth slightly rising response.


Matches very well to the measurements posted by So I'm confident that my close mic measurements are accurate.

Measurements @ 1 meter



The indoor responses (IN RED)between the 45's and the 65's shared the same characteristics. Keeping the huge hump that exists from 90hz to 200hz. This I imagine was the primary cause of the muddiness. Then the steady decline to 1khz, then a similar climb after 1khz and into the rest of the spectrum.

These speakers just behave terribly in my room (IN BLUE). Even with anticipating room reflections and modes that are going to wreak havoc on any graph, I’m still at a bit of a loss as to why they are sounding as they are.

In my situation, the SM 45s and 65’s sounded and graphed more similar to the Sony B-1000 (

 than my budget favorite Infinity Primus p143 in red. (

I will update to a single picture ASAP

The Def Techs are good looking and really well build. Massive heavy drivers that scream high quality. Their outdoor measurements indicate that they should be very good speakers, but they just do not seem to produce those same results in my room. I'm going to have to assume this is a one off experience and that I'm in the minority here. 

However this has been a great learning experience demonstrating how just one room can drastically affect sound and how if you are willing to spend this amount of money on some speakers you should do your best to try to listen to them before hand and even better see if your retailer of choice has a decent return policy if they don't work for your application.  

For now, I'll be keeping my previous generation Definitive Technology Studiomonitors. Below is a comparison between the 45 and 350's. The 350's are noticeably brighter and louder. This combo seems to not be as effected to my room conditions. 

Thursday, September 18, 2014

Does it pound?!?! DIY Home Depot Bucket Subwoofer using a Peerless 8 inch driver and BASH 300S amp

Here is my bucket subwoofer. While being bored during some down time at work, I looked for new DIY project and stumbled up this:

A small subwoofer using a 5 gallon bucket as an enclosure, awesome right?

So I gave it a shot; made some adjustments along the way and learned a good bit. Overall it was fun, but not without a few frustrations. I might have to try the sump sub next.:

Full album of step by step creation.

I started off with just a $3 Home Depot bucket and a dream.

I then cut the hole for the Peerless SLS 830667 Paper Cone Subwoofer and glued the hell of our the top and hammer it on to the bucket with a rubber mallet.

I decided to try and port this one, but I also wanted to give myself an easy out just in case I totally screwed up. So I integrated a way to close off the port and seal up the enclosure. 

Porting it seems to have worked well enough. From my fuzzy math it should be tuned to about 30hz. Did that actually happen? Probably not. See the test results at the end.

Concrete is poured in, about 1.5 inches deep and left to dry for a few days

Attaching the wood baffle for the driver, this is where I learned that these types of buckets are near impossible to actual glue anything to.  Polypropylene and Polyethylene low energy or inert or something else all sciency so 3M made an expensive magic glue to work on them. Thank God for screws then. When the cut out was made for the woofer, a lot of tension was taken off the bottom of the bucket which caused the left over "lip" that I was trying to mount the baffle to, to angle into the bucket. The glue and screws were an attempt to pull that lip back up and get a secure mounting surface. 

Painting time. I used truck bed liner, which also doesn't stick very well. But once it cures its tough enough to not flake off immediately. Never mind the nearly dead grass, this is California and if you have green grass right now then F you. 

Cheap, crappy speaker terminals form Radio Shack. Never again.

Mounting the woofer and putting some stuffing in. A whole bunch more as added just after this picture


Since the subwoofer enclosure is made of a bucket, I needed some where or someway to mount the BASH 300S plate amp. So since we are working with plastics, I found a handing file box at Staples that suited the amp well enough.

The future amp box

Drilling some pretty pretty air vent holes. I used a checker board pattern to make them nice and even-ish

Cut out for the amp done


So how did this thing actually turn out?

From just listening to music and watching a few movies, it definitely provides some kick and sounds pretty alright to me. Much louder than the Dayton Sub-800 that I normally have on all the time; and I think it might be darn close to besting the Dayton Sub-1200. Getting into more technical understanding on how well it blends or transient response and all that, Im not the best judge. I'm a car audio bass head who rolls around with an 18 in the back of my Ford Fusion so you can see where my priorities lie.

But I did take some in room responses so at least we can see a little bit of the technical results. So check these out. As a note, I'm still having trouble with REW, Dayton UMM 6 and my PC getting a consistent overall volume. You'll note that the graphs are centered around the 100 db mark, just prior to these testings, I was getting results centered around 80 db. Graphs look identical, just centered at the wrong point. 

Ported vs Sealed response. Not a huge difference, but audible for sure. Ported open is louder accross the usable spectrum. My room has clean peak at 100hz and that showed in all subs tested.

Bucket Sub vs Dayton Sub-1200. This was most supriseing. The bucket sub is louder than the Dayton from 50hz to 100hz and equal from 50hz to 35hz where the Bucket sub gets louder again. 

A few addition images of other sub tests can be seen below