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Harbottle Audio C18L2 personal review

dutchboy

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Hey fellas, it has been about 6 months since I received my Harbottle Audio C18L2 subwoofers and I thought this might be a good time to add to my original impressions. This is a subjective review of my experience and dealings with Harbottle Audio Ltd as a company and their CEO, Cody Hiebert as their principal director. I am simply a satisfied customer and not receiving any sort of compensation for this. While I was researching I really found peoples personal reviews to be helpful for me, and I would like to take the time to help others in the same boat. I apologize in advance for the length, I do not have the gift of brevity or good writing skills. I am simply and audio enthusiast.

So for those who missed it here is the original from late August:

I caught the audio bug at a young age and it never really left. I've always enjoyed the gear and hearing and feeling great music and great sound in general. Music and movies have always been an important part of my life both recreationally and therapeutically. I have been pursuing higher fidelity for 40+ years, 25 of which have occurred in the same living room. As I have matured in this hobby so have my wants and desires and it really has been a fun journey. I always enjoyed researching equipment to try and find the perfect blend of value and performance but recently aesthetics has been becoming more important to me. I have always had ported subs in the past and thought I would give sealed a try for the obvious reasons. At the level of gear I had I knew it would take a very special subwoofer to satisfy me as I have had several different subwoofers from PSA (15, 18, and dual 18”) and JTR (CAP 4000). My research lead me to Harbottle Audio and I began the long and enjoyable process of learning what makes these subs so special. I began with reading every thread and watching every video I find on the internet and ended with a call to Cody Heibert. Let me tell you, I was so excited and a bit intimidated to have a discussion with the actual engineer/designer/builder of Harbottle subwoofers. I am so glad I made the call and can't tell you how informational and helpful these conversations were in my decision making process. Learning what makes Harbottle products special from somebody as intelligent and passionate about great audio as Cody is was a wonderful experience. There was never any pressure, it was just wonderful to have every detail explained from a master of his trades on why things are the way they are. I placed the order and tried to remain patient. Talking with Cody helped me understand the product I was looking to purchase so much better, it really is reassuring.

As I was unboxing them I was just blown away by the absolute perfection and attention to every single detail paid to every single aspect of these units. They really are a pleasure to look at and touch. They are built and finished better than anything else I own.I got them hooked up and ran room correction and it was crazy...even the test tones sounded bad assed. The subwoofers are totally silent. I have experience with "hum” in the past and it is very frustrating to get to the bottom of.

Next I started listening to my favorite songs and I just couldn't believe it. I adjusted the gain to my liking and was just amazed and the sound and feeling I was getting from these things. The fidelity, resolution and impact is much better than I was expecting. It is one thing to read about and have LDLC explained to you, but please believe me when I say it is incredible to experience. I was expecting the typical tradeoffs talked about endlessly in every "which subwoofer should I buy, sealed or ported, and subwoofer comparison " thread I have read over the years. Imagine my disbelief when I realized that I had taken a substantial step forward in all aspects that mattered to me. I couldn't believe it. I finally now have the clean powerful, articulate and impactful bass I always wanted without any of the negative trade offs I thought I had to make. The dynamics and resolution are crazy, I mean the sound just starts and stops with such precision now. I immediately noticed and appreciated the lack of mechanical noise and resonances. Everything became more crisp, clear and felt more powerful. I really am hearing new details for the first time in my favorite content. I really look forward to the time I can spend enjoying my new and improved set up. It is hard to explain but, the room became so much quieter. I can still feel all of the tactile response in the suspended floor and on my body but there is no bloat. I had no idea a subwoofer could be so quiet reproducing subsonic frequencies. That goes double for room noise.

I can not overstate the value Cody himself brings to this. We have all read about his reputation my experience is it is well earned. The communication and knowledge he brings and shares is as peerless as it is priceless. When I try to consider all it must take to actually design and build a subwoofer of this caliber let alone the support, I realize just was a tremendous bargain these subs are. This is an entirely different level of insane quality and engineering from the ground up. Throughout this whole process, the more I learned the more I appreciate all of the tireless work and effort Cody, Caitlyn and crew put into making something like this possible for a guy like me to enjoy. I really had some high expectations for these subs and they were surpassed in every aspect. This company is crazy about producing the best possible product period. Nothing is overlooked and it all matters in the finished product. If somebody asked me "What makes these subs so great?" my simple answer would be "Everything". Every single part and component. The knowledge and attention to detail is astonishing and I really feel great being able to own and enjoy these subs. They really do make everything better for me from the mains to the room. I still can't believe how significant the improvement is. I wanted the best and I have them full stop, no more wondering. To get them at such a reasonable price almost seems too good to be true.

Now for the post calibration/integration part:

I have now had about 6 months with my C18L2’s and my appreciation for the company and products has only increased. My only regret was not making the upgrade sooner.As much as I love good audio I have always had a difficult time with the technical side of calibration. I knew I would never be able to get ever last spec of performance from these on my own. Out of the box with RoomPerfect RC and adjusting the gain gave me very enjoyable results, but purchasing a product from Harbottle doesn’t stop there. Early October I had a Harbottle Audio authorized integrator come and do a calibration. The integrator was great to communicate with and a pleasure to meet in person after talking several times on the phone to find out what my tastes and goals were for performance. He showed up promptly and immediately got to work testing the subwoofer and checking that everything is running to spec. I mean EVERYTHING, all of the parameters, settings and performance specs. There are like 500 qc checkpoints on each sub. When I loaded up some of my favorite music and movies to demonstrate the changes I was floored. It is a very good feeling to KNOW you have the best subwoofer running at peak performance. My main speakers have never sounded so good. I was really surprised. The imaging is totally insane. It really sounds like music is coming from all over the room. I have to walk up and put my ear next to the center and surrounds just to make sure I am in stereo mode. But wait, I have said this before…it even gets better. In addition to getting the peace of mind that comes from knowing everything is running optimally you also get an entire year added to the warranty! For me this was very reassuring. All of the tremendous amount of work that went into the sub, DSP and calibration get saved and stored with the company so if anything ever happens solutions can be found in the best way possible. I did not just buy two world class subwoofers, I got the entire world class package.

I have only owned ported subs in the past and have spent years on the forums reading and rereading that it takes 3 sealed subs to equal the output of a similar spec’ed ported subwoofer. I took it as gospel. Being as I was coming from a JTR CAP 4000 I was a little apprehensive. When I read Michael Steven’s (Youthman) comment on Facebook “Harbottle makes great subs with similar performance as JTR They just cost 3 times as much.” I have to chuckle and wonder if he has ever heard a Harbottle Audio subwoofer. On paper a CAP should smoke the C18 but that was not my experience at all. I mean I understand he is a salesman/agent, but I have had them both in the same room at the same time, there is simply no comparison to be made on performance, build quality or engineering. The increase in dynamics and lack of compression and distortion is stunning. Please do yourself a favor and go to Harbottle Audios website and look around if you are considering a end game subwoofer. The website is chuck full of information documented studies and data. When you call Cody you get knowledge, science, and physics not sales pitch or hype so be prepared. I am always careful asking engineers questions about how and why things work the way they do, but he would always take the time to explain the physics and engineering principles completely in a way that I could understand (not as easy as it sounds :). I have pages of notes from my interactions with him.

I have watched and read every interview I could get my hands on prior to my purchase and I knew Cody was the tip of the spear in subwoofer engineering, designing and building. I have always thought that if there is anything that portrays excellence and confidence in a product by a company it is the and guarantees and warranty. Most subwoofer companies post specs and performance stats, Harbottle Audio guarantees them. These subwoofers are made to be used and enjoyed at full capacity with content for extended periods of time. The testing they go through before they ever leave the shop is like nothing I have ever read about from any audio company.

I really hope people considering Harbottle Audio find this helpful as that was my goal. As always if you have any questions please contact:


Cody H. | Director | Harbottle Audio Ltd.
www.harbottleaudio.com
Whatsapp, Phone, & Text 604-341-6875

Here are some pics of the subwoofers during final assembly and and in room

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I have had them both in the same room at the same time,

You had this opportunity to do a double-blind test and didn't follow through? Shame on you for throwing such a wonderful opportunity away!

The remainder of your comments are the result of sighted listening. They are obviously your (enthusiastic) opinions, but they have no statistical validity, not being backed up by rigorous scientific controls.
 
Nice subs! No scientific type info at all, like setup procedure or measurements ? Cost?
 
Nice subs! No scientific type info at all, like setup procedure or measurements ? Cost?
Thank you Chrispy

As stated Harbottleaudio.com is loaded with scientific and engineering type info, if that is what you are looking for please visit the website and have a look around be sure to look at the sections labeled "Nerd Stuff and "Directives and FAQ's". I hope you find it as interesting as I did.

All of the set up and measurements were done and are being kept by the authorized integrator. I stated several time in the review I am not technically proficient at calibration and integration.

I tried to state all of this in the opening paragraph and in several places throughout the review but perhaps I was unclear, sorry about that.

Regards,

Chad
 
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Thank you Chrispy

As stated Harbottleaudio.com is loaded with scientific and engineering type info, if that is what you are looking for please visit the website and have a look around be sure to look at the sections labeled "Nerd Stuff and "Directives and FAQ's". I hope you find it as interesting as I did.

All of the set up and measurements were done and are being kept by the Authorized integrator. I stated several time in the review I am not technically proficient at calibration and integration.

I tried to state all of this in the opening paragraph and in several places throughout the review but perhaps I was unclear, sorry about that.

Regards,

Chad
I reread the post, still not much help on the setup question. Authorized is an integrator brand of some sort? was it in home or remote? I've been following Funk for a long time....
 
Subjectivity has a place. We can't help but employ it, every single day of our lives. I employ it to enjoy my audio system, and I see that you employ it to enjoy your audio system. I'm glad that you enjoy your audio system. I'm sure that you're proud of it.
But ... subjective impressions given to other people with no data are, at best, ambiguous. More commonly, they are misleading, since subjectivity has no factor of reproducibility.
( https://en.wikipedia.org/wiki/Reproducibility )

For reviews like that, there are dozens (or even hundreds) of YouTube sites and several subjectivist publications.

ASR tries to do better, as shown by this video.

That video came from here. And the reason controls are needed is answered here.
 
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You had this opportunity to do a double-blind test and didn't follow through? Shame on you for throwing such a wonderful opportunity away!

The remainder of your comments are the result of sighted listening. They are obviously your (enthusiastic) opinions, but they have no statistical validity, not being backed up by rigorous scientific controls.
Hey Jim,


Believe me, the thought of doing double blind did occur to me, but that is easier said than done. I have really enjoyed reading them over the years, but I really don't have the capability to pull one off that would be statistically valid. I have spent years reading on ASR and I guess I expected to get called out on it but not on the first post :D
There is a whole lot of work that goes into a valid double blind test. Have you ever had the opportunity to conduct one?

Regards,

Chad
 
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Chad, thanks very much for sharing your experience. Your system is gorgeous and no doubt sounds fantastic. You made it clear it was a subjective report; blind comparisons are great but very difficult to conduct properly. Your experience with the company and subsequent calibration process was very useful for me.
I think there should be room in this forum for intelligent and thoughtful subjective comments; I look forward to hearing more about your experience with your setup.
Enjoy
 
Hey Jim,

Believe me, the thought of doing double blind did occur to me. I have really enjoyed reading them over the years, but I really don't have the capability to pull one off that would be statistically valid.

Regards,

Chad

Yes, I certainly understand that! As much as I favor DBTs, I realize that to have value, any test, DBT included, needs to comply with all necessary protocols. I also realize that is a huge pain in the ... neck. :p
 
I reread the post, still not much help on the setup question. Authorized is an integrator brand of some sort? was it in home or remote? I've been following Funk for a long time....
Good Morning Chrispy,

I should have used the words "Certified Representative" to avoid confusion...

When I placed the order for my subs, things were a bit different. They only offered 4 versions of the carbon series - A 18" and 24" model with two different performance ratings, now they offer tons of different combinations based on what ever your requirements or goals are.
Here is a page I pulled from the website that does a better job describing the relationship better than I can, followed by a page that explains the order process for the Carbon series subwoofers which is what I have.

I also have followed Funk Audio for a long time and there is a strong affiliation. At the time I placed my order I believe Nathan Funk was building the enclosures and Cody was building the drivers and amps as well as handling the DSP programing.

I hope this clears things up a bit.

Chad

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Chad, thanks very much for sharing your experience. Your system is gorgeous and no doubt sounds fantastic. You made it clear it was a subjective report; blind comparisons are great but very difficult to conduct properly. Your experience with the company and subsequent calibration process was very useful for me.
I think there should be room in this forum for intelligent and thoughtful subjective comments; I look forward to hearing more about your experience with your setup.
Enjoy
You're welcome ex audiophile.
It is nice to hear someone found my review helpful.

Chad
 
Good Morning Chrispy,

I should have used the words "Certified Representative" to avoid confusion...

When I placed the order for my subs, things were a bit different. They only offered 4 versions of the carbon series - A 18" and 24" model with two different performance ratings, now they offer tons of different combinations based on what ever your requirements or goals are.
Here is a page I pulled from the website that does a better job describing the relationship better than I can, followed by a page that explains the order process for the Carbon series subwoofers which is what I have.

I also have followed Funk Audio for a long time and there is a strong affiliation. At the time I placed my order I believe Nathan Funk was building the enclosures and Cody was building the drivers and amps as well as handling the DSP programing.

I hope this clears things up a bit.

Chad

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View attachment 430236
Still doesn't actually answer my question, altho it clarifies who might have been involved but vaguely....if you're in Illinois did Nyal Mellor or Jeff Mery handle it and how did they accomplish integration....or did they at all?
 
Still doesn't actually answer my question, altho it clarifies who might have been involved but vaguely....if you're in Illinois did Nyal Mellor or Jeff Mery handle it and how did they accomplish integration....or did they at all?

His integration was performed by a Representative in training. I have been working with him for over 5 years as a ODM client. At this time he is choosing to keep a low profile as he builds knowledge, aquires certifications, and builds his company. On this calibration, he worked under Jeff Merys supervision.
Set up procedure was limited to the positions as per the spots Chad had available, see photos. From there, our rep simply used room measurements and his HAA training to discern what the room was capable of delivering and where the limitations are, followed by some fine tuning and suggestions; upgrade to 220 VAC for about 1.5 more dB, add a thrid subwoofer for smoothing effects, and so on.
 
@dutchboy Chad. You mention having used PSA and JTR...both are great subs. What was the difference between the Harbottle and this subs? And then you mention another "bump" in quality after further calibration. What was that? Better blending with the speakers?
 
Good Morning kma100,

"Chad. You mention having used PSA and JTR...both are great subs. What was the difference between the Harbottle and this subs?"

I believe the short answer is LDLC. The higher the volume the more obvious it gets.
Some examples of the things I noticed right off the bat were the increase in dynamics, precision and detail, followed by the lack of noise coming from the subwoofer and room. Things sounded much more precise without the room resonances. I know it has become cliche, but the increase in clarity allowed me to hear more subtle details in my favorite content. I could still hear and feel the low and ultra low frequencies but without the bloat, overhang and mechanical noise from my favorite music and movies.
It was also very obvious when I played all of the test tone tracks and super low bass music that I use for fun and demos and on the frequencies that are too low to actually hear (like Bass Mekanik & Senhor De Baixo) subwoofers are much more quiet reproducing them.

For the record with the PSA & JTR setups I had remote calibrations done by established professionals.

"And then you mention another "bump" in quality after further calibration. What was that? Better blending with the speakers?"

Yes, the room correction did a good job, but the advanced work in timing and crossover/blending added further refinement.
When I listen to good stereo music the imaging is just crazy and so enjoyable, the it really sounds like the musical instruments are coming from all over the place.
 
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Some examples of the things I noticed right off the bat were the increase in dynamics, precision and detail,

How did you know that there was an increase in these characteristics if you did not have the benefit of A/B comparisons? Although a double-blind test would be necessary to lend validity to such statements, the lack of even the most rudimentary A/B comparison means that you were relying on your auditory memory for comparison of the "details".
Auditory memory in humans is both poor and fleeting. That's one reason that double-blind tests are made with very quick switching.

Another problem is output level. If the output level is not matched, cognitive bias will favor the louder device under test.
 
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Good Morning kma100,

"Chad. You mention having used PSA and JTR...both are great subs. What was the difference between the Harbottle and this subs?"

I believe the short answer is LDLC. The higher the volume the more obvious it gets.
Some examples of the things I noticed right off the bat were the increase in dynamics, precision and detail, followed by the lack of noise coming from the subwoofer and room. Things sounded much more precise without the room resonances. I know it has become cliche, but the increase in clarity allowed me to hear more subtle details in my favorite content. I could still hear and feel the low and ultra low frequencies but without the bloat, overhang and mechanical noise from my favorite music and movies.
It was also very obvious when I played all of the test tone tracks and super low bass music that I use for fun and demos and on the frequencies that are too low to actually hear (like Bass Mekanik & Senhor De Baixo) subwoofers are much more quiet reproducing them.

For the record with the PSA & JTR setups I had remote calibrations done by established professionals.

"And then you mention another "bump" in quality after further calibration. What was that? Better blending with the speakers?"

Yes, the room correction did a good job, but the advanced work in timing and crossover/blending added further refinement.
When I listen to good stereo music the imaging is just crazy and so enjoyable, the it really sounds like the musical instruments are coming from all over the place.

You are correct. From a science perspective LDLC is a engineering envelope that only allows for 1 dB compression at Xmax (inaudable compression) and inaudible distortion. So when these two aspects of audio playback are reduced to the inaudable spectrum, then the dynamic range has a higher ratio of recorded audio signal and inaudible compoenents of noise.
The logical reasoning is that when the dynamic range is more full of clean playback, the listener hears more clean playback and the sonic signature thereby can not change until the thermal limit of the driven unit or the power supply limit of the amp because the compressive profile and distortion profiles are limited to inaudible right up to the thermal limits of the driver.
 
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Good evening, @Harbottle Audio !. Is this the LDLC to which you refer?


Hz SPL % THD dB COMPRESSION
LDLC %THD dB Compression 2nd order 3rd order 4th order 5th order
10 38 1 -10 -15 -20 -25
12.5 35 1 -11 -16 -21 -26
16 32 1 -11.5 -16.5 -21.5 -26.5
20 29 1 -12.35 -17.35 -22.35 -27.35
25 25 1 -13.5 -18.5 -23.5 -28.5
32 20 1 -15.5 -20.5 -25.5 -30.5
40 14 1 -18.5 -23.5 -28.5 -33.5
50 9 1 -22.5 -27.5 -32.5 -37.5
63 7 1 -24.5 -29.5 -34.5 -39.5
80 5 1 -27.5 -32.5 -37.5 -42.5
100 4 1 -29.5 -34.5 -39.5 -44.5
125 4 1 -29.5 -34.5 -39.5 -44.5
CEA 2010 limits
10 38 not limited -10 -15 -20 -25
12.5 38 not limited -10 -15 -20 -25
16 38 not limited -10 -15 -20 -25
20 38 not limited -10 -15 -20 -25
25 38 not limited -10 -15 -20 -25
32 38 not limited -10 -15 -20 -25
40 38 not limited -10 -15 -20 -25
50 38 not limited -10 -15 -20 -25
63 38 not limited -10 -15 -20 -25
80 38 not limited -10 -15 -20 -25
100 38 not limited -10 -15 -20 -25
125 38 not limited -10 -15 -20 -25
 
I believe that Harbottle products have already been discussed on ASR:

 
Good Morning kma100,

"Chad. You mention having used PSA and JTR...both are great subs. What was the difference between the Harbottle and this subs?"

I believe the short answer is LDLC. The higher the volume the more obvious it gets.
Some examples of the things I noticed right off the bat were the increase in dynamics, precision and detail, followed by the lack of noise coming from the subwoofer and room. Things sounded much more precise without the room resonances. I know it has become cliche, but the increase in clarity allowed me to hear more subtle details in my favorite content. I could still hear and feel the low and ultra low frequencies but without the bloat, overhang and mechanical noise from my favorite music and movies.
It was also very obvious when I played all of the test tone tracks and super low bass music that I use for fun and demos and on the frequencies that are too low to actually hear (like Bass Mekanik & Senhor De Baixo) subwoofers are much more quiet reproducing them.

For the record with the PSA & JTR setups I had remote calibrations done by established professionals.

"And then you mention another "bump" in quality after further calibration. What was that? Better blending with the speakers?"

Yes, the room correction did a good job, but the advanced work in timing and crossover/blending added further refinement.
When I listen to good stereo music the imaging is just crazy and so enjoyable, the it really sounds like the musical instruments are coming from all over the place.
More sounds like you have no particular idea of how things work and use some different subjective impressions at different times to somehow compare.....good luck with that.
 
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