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Helios CM Comparison

Reigningchamp

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Hey everyone, I'm considering building a pair of the Helios CM's by Jeff Bagby and Javad Shadzi, but there's very little information out there on its performance. Does anyone have any listening experiences or comparisons they could make? I'm also heavily considering the Philharmonic BMR kit as it's in a similar size (ish) and price range, but I can't find anyone that has listened to both of these. These will be in a relatively small listening room 12'x12' and I will not use a sub.
 
Please, avoid the CM. Build the real deal original Helios.
I've heard both, and did not like the CM at all. Tweeter distorts, PR is tuned too high, and the not-so-novel xover is not doing the job as it should.
My Zingers sound better than the CM for a lot less outlay, but that is my opinion.
 
Unless you are wanting a different finish, I am not sure the cost savings on a BMR kit is worth it. The pics I have seen of the finished cabinets look really nice for not a large difference in price.
 
Unless you are wanting a different finish, I am not sure the cost savings on a BMR kit is worth it. The pics I have seen of the finished cabinets look really nice for not a large difference in price.

I agree, considering the cost of the kit keeps going up and up. After wood, maybe some tooling, and lots of time, to me it's barely worth buying the kit considering how incredible the finish is on the premade BMR's.
 
40A6DBAB-50FA-4955-B3F6-7D3B92D6EC47.jpeg
Please, avoid the CM. Build the real deal original Helios.
I've heard both, and did not like the CM at all. Tweeter distorts, PR is tuned too high, and the not-so-novel xover is not doing the job as it should.
My Zingers sound better than the CM for a lot less outlay, but that is my opinion.
Ben I am just seeing this…as the co-designer of this kit I’d like to respond to these “opinions” that Ben or “Wolf” has posted.

“Tweeter distorts” - patently false and easily proven with measurements, I’m happy to post some distortion measurements to prove this is a blatantly false statement. I have listened to this speaker design for hundreds of hours, it simply does not audibly distort until the woofer reaches excursion limits at low frequencies at very high SPL, above 105db 1-meter.

“PR is tuned too high” - PR is tuned to 31 Hz, totally false, this speaker is flat to 40hz in room up to over 95db, and has strong output at 30hz thanks to the PR tuning frequency which doesn’t unload the woofer until 20hz and lower.

“Crossover isn’t doing its job” - this is hyperbole, take a look at the gated measured in room response, this passive crossover is doing an excellent job at managing the response and woofer and being perfectly in-phase through the crossover region.

Ben you then suggest one of your own designs which makes it seem that this is all about self promoting yourself along with some false feedback about this design.

Javad Shadzi
 
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Javad, no disrespect was intended, nor was it supposed to be promoting my own stuff. I just posted my opinion, and something for comparison. I do feel the Helios is superior to the CM.

I was not the only person who came away with this opinion either, and at least 2 others also told me so in Grand Rapids.
 
Javad, no disrespect was intended, nor was it supposed to be promoting my own stuff. I just posted my opinion, and something for comparison. I do feel the Helios is superior to the CM.

I was not the only person who came away with this opinion either, and at least 2 others also told me so in Grand Rapids.

Glad to hear you meant no disrespect but your feedback about the design is simply factually false.

If you didn’t like the way they sounded fine, that’s your opinion, but that’s not what you said here.

I was at Grand Rapids and heard the speakers playing myself, there was no distortion and I had many people give unsolicited feedback that they sounded excellent.

Yes the Helios uses a 9.5” Satori woofer and a $600 Be tweeter, it also costs twice as much to build, most would agree it sounds better than the CM but many actually prefer the CM and as such the kit has been very popular at Meniscis.

Cheers,

Javad Shadzi
 
Hi Javad,

Why do they prefer it?

Do they prefer it because of sonic preference or because it is a lower cost kit? Both of these are difficult to argue with.

Some people prefer the original for sentimental reasons. That’s hard to argue with too. Jeff Bagby had a loyal following due to his honest contribution to DIY audio- and from my correspondence with him liked to build smaller and high value.

I just knew I wanted to build one of Jeff Bagby’s last small speakers (Revolution mini), so I get that sentimentality.

If they prefer it because it is better value kit then I think the value equation is up to the end user.

For people who build one offs and spend dozens of hours in the garage, a few hundred (or thousand) dollars on drivers is not really a big ask. (In Australia minimum wage is $20/hr (US$13.5/hr) so any pair of cabinet costs hundreds if not approaching a thousand; unless it’s made by a kitchen cabinetmaker via CNC; or one is not considering opportunity cost- hobbyist; student; retired)) I can see why someone might recommend springing for Satori drivers and the original design. Those Danish or Finnish loudspeaker designers have the same problem- it costs a bomb to get any cabinets made locally to entire thing become unpalatable.

For me it’s fascinating to hear comments of perception of treble or bass preference or crossover integration, despite the in-room measurements looking reasonably good (tuned slightly ripe as can be seen in the lift below 100Hz)

Though I never understand why Jeff liked to show gated in-room measurements. Why not show quasi-anechoic measurements as designed. Or is that a feature or limitation of Omnimic?

(Sorry I never used Omnimic)
 
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Hi Javad,

Why do they prefer it?

Do they prefer it because of sonic preference or because it is a lower cost kit? Both of these are difficult to argue with.

Some people prefer the original for sentimental reasons. That’s hard to argue with too. Jeff Bagby had a loyal following due to his honest contribution to DIY audio- and from my correspondence with him liked to build smaller and high value.

I just knew I wanted to build one of Jeff Bagby’s last small speakers (Revolution mini), so I get that sentimentality.

If they prefer it because it is better value kit then I think the value equation is up to the end user.

For people who build one offs and spend dozens of hours in the garage, a few hundred (or thousand) dollars on drivers is not really a big ask. (In Australia minimum wage is $20/hr (US$13.5/hr) so any pair of cabinet costs hundreds if not approaching a thousand; unless it’s made by a kitchen cabinetmaker via CNC; or one is not considering opportunity cost- hobbyist; student; retired)) I can see why someone might recommend springing for Satori drivers and the original design. Those Danish or Finnish loudspeaker designers have the same problem- it costs a bomb to get any cabinets made locally to entire thing become unpalatable.

For me it’s fascinating to hear comments of perception of treble or bass preference or crossover integration, despite the in-room measurements looking reasonably good (tuned slightly ripe as can be seen in the lift below 100Hz)

Though I never understand why Jeff liked to show gated in-room measurements. Why not show quasi-anechoic measurements as designed. Or is that a feature or limitation of Omnimic?

(Sorry I never used Omnimic)

I have not surveyed those who have built the HeliosCM kit to know to the degree you are discussing why they like it specifically, feedback has been great that those who have built the kit enjoy the sound, there is no audible tweeter distortion as has been claimed, and that the speaker has a smooth, accurate and balanced sound - which is the goal of all my designs as well as those I am involved with.

Regarding the response, that is an in-room gated response which means below 250hz, room reflections are entering the measurement and it's not representative of the actual response of the speaker. Moving the speaker around in the room will result in different measured responses. The bass response of this speaker is flat and sounds accurate, uncolord and in balance with the rest of the audio spectrum being produced.

Cheers,
Javad Shadzi
 
All you seem to be doing here is trying to make my opinion on the sound go away. If I dont comment, I look like I was in the wrong. If I do comment, there is no HD graph to analyze and I still look like I'm in the wrong.
FWIW, this is not the only place on the internet where I've posted my thoughts on this design.
 
This is an issue @Wolf

As designers we are a little biased towards our babies, that is understandable.

Cognitive biases are very difficult spot in ourselves - it’s much easier for others to spot. Research has shown this- when we are reading something written by someone else, it is much easier to be critical about it, then if we are reading about something we’ve personally written (scientific article, policy etc)

This is the one of the main reasons for peer review in many scientific fields. The gold standard is double blinded randomised trial; and more than one, eg. meta-analysis ; but of course this is very difficult to do for 2 speakers with a large group of people, as much depends on the ancillary equipment and room; and even whether it can be externally valid (ie. holds true in my room or your room or equipment)

@JShadzi I’d love to hear your critique on my cabinetry. Your industrial design and woodworking are amazing and I like looking at what can be achieved without CNC.

And I’m confident when @Wolf hears something; there’s something to it; so I wouldn’t dismiss it when he critiques any design. I mean Wolf has been doing crossovers by ear and single on-axis measurements with passive crossovers before many of us were doing it with the help of CAD or full 360 degree quasi anechoic measurements and real time DSP for crossover development.

So it would be interesting to understand what he means by what he says. Sometimes one person’s distortion is another person’s “extra detail”. Or maybe due to extra energy around 2-3Khz. Certainly there’s bunching up there:
93BD864A-B013-46CF-95BE-B6F54BBA7211.jpeg

it would be interesting to see what the power response or DI is around that region.
And one persons “PR tuned too high” is another person “I’ like it!! Just right amount of punchy bass”

In my professional field it’s a bit rude criticise other people practice. But we all need to be able to do it, and receive it. And there may be safe spaces to do it, or different ways of approaching it, which we all need to all receptive to a) to continue learning b) be made aware of our blind spots c) be accountable and not go rogue and endanger others or ourselves.
In audio you might not endanger someone’s life; but you can certainly diminish the reputation of your whole field by going off the deep end and end up spruiking something false, even if your intentions were good.

One my earliest teachers never said that I did it wrong. He would always say “hmm. That’s one way to do it… are there any other ways to approach it?”
 
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This is an issue @Wolf

As designers we are a little biased towards our babies, that is understandable.

Cognitive biases are very difficult spot in ourselves - it’s much easier for others to spot. Research has shown this- when we are reading something written by someone else, it is much easier to be critical about it, then if we are reading about something we’ve personally written (scientific article, policy etc)

This is the one of the main reasons for peer review in many scientific fields. The gold standard is double blinded randomised trial; and more than one, eg. meta-analysis ; but of course this is very difficult to do for 2 speakers with a large group of people, as much depends on the ancillary equipment and room; and even whether it can be externally valid (ie. holds true in my room or your room or equipment)

@JShadzi I’d love to hear your critique on my cabinetry. Your industrial design and woodworking are amazing and I like looking at what can be achieved without CNC.

And I’m confident when @Wolf hears something; there’s something to it; so I wouldn’t dismiss it when he critiques any design. I mean Wolf has been doing crossovers by ear and single on-axis measurements with passive crossovers before many of us were doing it with the help of CAD or full 360 degree quasi anechoic measurements and real time DSP for crossover development.

So it would be interesting to understand what he means by what he says. Sometimes one person’s distortion is another person’s “extra detail”. Or maybe due to extra energy around 2-3Khz. Certainly there’s bunching up there:
View attachment 280183
it would be interesting to see what the power response or DI is around that region.
And one persons “PR tuned too high” is another person “I’ like it!! Just right amount of punchy bass”

In my professional field it’s a bit rude criticise other people practice. But we all need to be able to do it, and receive it. And there may be safe spaces to do it, or different ways of approaching it, which we all need to all receptive to a) to continue learning b) be made aware of our blind spots c) be accountable and not go rogue and endanger others or ourselves.
In audio you might not endanger someone’s life; but you can certainly diminish the reputation of your whole field by going off the deep end and end up spruiking something false, even if your intentions were good.

One my earliest teachers never said that I did it wrong. He would always say “hmm. That’s one way to do it… are there any other ways to approach it?”I

I do respect Ben and his speaker design skills, in fact I've taken his critiques many times and I've always treated him with respect. Unfortunately for him his criticisms here were created out of thin air, briefly listening to a speaker for a few minutes. So as you say, he is spurning something false, and I take objection to that and have listed my responses above in the thread.

His last false claim that I will debunk is that the tweeter is distorting audibly, that's verifiably false.
I have uploaded some distortion plots, even at 100db 1-meter tweeter distortion never rises above .31% THD, 3rd order peaks at .13%, and is below .1% for all of the tweeter passband. This is very loud, much louder than most would listen to and louder than when Ben heard this speaker breifly.

This is a Jeff Bagby crossover design that I assisted with, yes there is a small amount of bunching which is very common in all speakers that don't have total controlled directivity, every one of Ben's designs will have bunching but even worse if they do not use a waveguide. Bunching affects a speaker's power response and needs to be accounted for in the voicing of the speaker, as we have done here.

Nobody has claimed this is the best sounding speaker in the world, it's certainly not perfect, but it is an optimized design that sounds great.

I run a large Facebook group dedicated to speaker building and design, we encourage constructive critical feedback and we ask member to support their claims, I am not new to being criticized and learning from feedback, and as I said, I have learned things from Ben in the past too as I have always been open to truthful and correct feedback.

Cheers,
Javad Shadzi
 

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All you seem to be doing here is trying to make my opinion on the sound go away. If I dont comment, I look like I was in the wrong. If I do comment, there is no HD graph to analyze and I still look like I'm in the wrong.
FWIW, this is not the only place on the internet where I've posted my thoughts on this design.
Ben when you go online and make false claims publicly it makes you look bad and could hurt your reputation, yes, and that's on you. I'm not trying to make you look bad, I am responding to the false claims you have made. If you don't like the way they sound after hearing them for a few minutes at a DIY event no problem, but that's not all you've said here.

Javad Shadzi
 
Thank you for showing the plots I asked for, Javad. It seems indeed clear from this information that what I and the other 2 people heard was not signal distortion from the tweeter, nor likely related to the Fs magnitude as i previously presumed.
This however just means that the root cause of what I experienced is truly an unknown, and an anomaly that may just be how that driver sounds as implemented. It may very well be that I/we just didn't like it after all. I really wanted to find out the root cause, as we heard something, measured or not. It doesn't change how I feel about the sound, nor that I find the original Helios to sound better. It is worth saying i am not in general a waveguide user or fan, but some waveguided designs have sounded good to me. YMMV.

I also would like to say that the xover network is tailoring the system response as the designer intended, and was not the issue I took with it "doing its job". I feel this does need stated here so it is understood that a circuit arrangement or topology involved herein was something I adamantly oppose for xover use. Javad and I just differ on whether this is something that should or not be used. I am wording it this way so to not reveal the usage, as apparently the total circuit has not been released to the public. I only know what I know from the statements of Javad prior presenting it to the attendees present.
Please see this as a clarification and not a retraction. I don't prefer the topology, but it was sufficient in effect.

In reference to my methods above...
Let me also say that I do not just look at on axis responses. Just because that is the main result PCD shows or that it's what a lot of users reference does not mean I don't look at them. The Power Response that PCD shows is essentially an inverted DI curve, and i do model the off axes at the very least. I'd also like to mention that controlled directivity is not the only way to design a result even if it is the current trend. I tend to prefer a bit broader off axis response so that I can move seating positions and still get focus from both channels so that imaging and Soundstage don't suffer. I also prefer a clean, maybe slightly 'lively' tonality, or what I call more "realistic" than "neutral", and moreover, a flat non-tilted or angled on axis response.
 
Thank you for showing the plots I asked for, Javad. It seems indeed clear from this information that what I and the other 2 people heard was not signal distortion from the tweeter, nor likely related to the Fs magnitude as i previously presumed.
This however just means that the root cause of what I experienced is truly an unknown, and an anomaly that may just be how that driver sounds as implemented. It may very well be that I/we just didn't like it after all. I really wanted to find out the root cause, as we heard something, measured or not. It doesn't change how I feel about the sound, nor that I find the original Helios to sound better. It is worth saying i am not in general a waveguide user or fan, but some waveguided designs have sounded good to me. YMMV.

I also would like to say that the xover network is tailoring the system response as the designer intended, and was not the issue I took with it "doing its job". I feel this does need stated here so it is understood that a circuit arrangement or topology involved herein was something I adamantly oppose for xover use. Javad and I just differ on whether this is something that should or not be used. I am wording it this way so to not reveal the usage, as apparently the total circuit has not been released to the public. I only know what I know from the statements of Javad prior presenting it to the attendees present.
Please see this as a clarification and not a retraction. I don't prefer the topology, but it was sufficient in effect.

In reference to my methods above...
Let me also say that I do not just look at on axis responses. Just because that is the main result PCD shows or that it's what a lot of users reference does not mean I don't look at them. The Power Response that PCD shows is essentially an inverted DI curve, and i do model the off axes at the very least. I'd also like to mention that controlled directivity is not the only way to design a result even if it is the current trend. I tend to prefer a bit broader off axis response so that I can move seating positions and still get focus from both channels so that imaging and Soundstage don't suffer. I also prefer a clean, maybe slightly 'lively' tonality, or what I call more "realistic" than "neutral", and moreover, a flat non-tilted or angled on axis response.

Ben thank you for the response, I feel you've made a bid to be reasonable and put your statements in a more accurate light which I appreciate.

We can agree to disagree on the sound. You heard the speakers very briefly in a large hotel conference room filled with people, and I remember where you were sitting, I'll just say you had hardly a "critical listening" experience, I would not be able to make definitive statements as you have with the limited listening you had. I'd be happy to arrange a time for you to critically listen to these if we can arrange it. In the future before publicly criticizing a speaker I have designed or helped design, I'd love for you to have a more meaningful listening experience if you'd like.

I'm not here to convince you to like what you heard, only to address the definitive points you had made which were easily verifiable.

Thank you Ben, see you the weekend after next, cheers.

Javad
 
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