Verdant Audio Bambusa MG 1 Speaker Review

[Alice of Old Vincennes]

I think I'll watch Babadook tonight

 

[Selah Audio]

Extremely normal design using very capable drivers. I'm sure a lot of tuning by ear was done. Sort of funny to see that cheap port on a speaker with such nice drivers.

What's sort of funny about this speaker is that this is almost a best-case scenario for smooth directivity using drivers mounted on a 180 degree waveguide; very robust tweeter allowing a low and shallow crossover, smaller woofer with fairly extended HF, although breakup can be an issue. Amir still points out the bump in the DI, but most speakers are going to be quite a bit worse; there are countless speakers using dome tweeters and 18cm woofers and that bump in the DI will be a lot worse.

Reading the website of the producer, looks like this is a DIYer turned manufacturer, so I wish him all the success in the world, but god help you if you're spending $200 on a woofer to make a speaker which performs worse than what Revel can offer at significantly less using cheap drivers (lower end models.)

The size of our ambitions are limited by our understanding of the world - I used to want to make speakers like this, and since I lusted after the most expensive drivers offered by Madisound/PE/Solen/etc I assumed that the 'ultimate' speaker was one that used Eton or ScanSpeak or Transducer Labs or RAAL drivers. Since then I've come to understand that a SEAS Millenium tweeter has far more in common with every other 25-28mm dome tweeter than it is different, and that to create great sound required a bit more knowledge.

ASR is slowly showing that excellent speaker designs are not dependent on the things DIYers obsess over - expensive drivers, ultra inert cabinets, diffraction treatment, complex crossovers using tons of expensive capacitors and foil inductors, copper binding posts, etc. It depends on 3d measurements and their careful interpretation, which in fairness some DIYers obsess over.

Many of the DIY builders have mostly focused on a flat on-axis response. The camp that you note has paid more attention to the ingredients than the recipe.

 

[Selah Audio]

If you're going to match a 1" dome to a large(ish) midrange, and not compromise either the direct or reflected sound, you will need a waveguide, crossing it lower would make matters worse in case of leaving it without. Surely someone with your pedigree knows this? This isn't about herd mentality rather than physics.
Alternatively, add a 2-3" midrange and you can pretty much discard the waveguide, keep directivity even and wide, without any compromise in the direct sound.

I get what you're saying - I just am pointing out that the results could be much better with this driver combination (I've used both drivers in past designs). A 3-way with a small mid would certainly help but that's not a guarantee of smooth constant directivity. Some of the small mids have very little directivity control due to the design of the driver.

 

[Selah Audio]

The obvious comment here is - why is a flat baffle, effectively a 180 degree waveguide with edge diffraction superior to restricted coverage? Have you ever designed a speaker with minimal baffle around the tweeter, for example?

For the most part I agree with you but the gentle shallow waveguides such as those used by revel and many diyers seem to be a great compromise between the uncolored sound of direct radiators and the performance of more hornish configurations. Even the SS 9900 has a waveguide you could argue.

On a separate note have you heard the big wavecor waveguide unit?

Most domes have semi-horn loading / waveguides / contoured faceplates and the 9900 is an exceptional design. I would prefer it over the Seas tweeter used in the speaker being reviewed.

 

[jhaider]

Cliff's notes: $5k for a poor crossover/spacing design and low-80's sensitivity? Company's page has some stuff that just seems silly. Pass.

That, and maybe it's just me, but the terrible pattern matching between baffle and endcaps makes the speaker look like a DIY project where somebody ran out of cabinet material and had to make it work somehow.

In my initial work, I made the same cabinets out of MDF, Baltic birch, bamboo, cf reinforced ABS that was 3D printed, fiberglass and carbon fiber, both with Nomex cores.
I used the same drivers and crossovers in each and evaluated them in terms of sound profile and detail listening to the same songs taking careful notes.

That sounds like a basic workflow error: sighted listening and no data. I am not sure what you expected to get out of that exercise, or how it adds value to anyone else. It's worth noting that the best loudspeaker designers talk very little about sighted listening and more about measurement techniques when one probes into their design workflows.

the real market for active speakers is that there is no need for additional amplifiers and wires. Takes up a lot less space. That is why I feel like the plate amp is essential.

Free advice: the to-my-knowledge unexplored "happy medium" is a cabinet the same footprint and finish as the speaker containing the electronics, such that it could either fit elegantly under the speaker or be placed remotely. For an OEM there is also the benefit of hiding control interfaces. Only a power switch, I/O, and whatever LEDs are desired need be visible to the consumer. Dealers should like the solution, because they can still sell short lengths of magic speaker cables to the gullible. The other benefit is a customer with existing house wiring can remotely locate the electronics. I am puzzled nobody seems to have brought such an active speaker to market.

 

[Selah Audio]

Something went wrong on that 400hz distortion spike. That wouldn't be due to the drivers.

 

[Deleted member 2944]

Something went wrong on that 400hz distortion spike. That wouldn't be due to the drivers.

Yeah, I would agree. Some sort of measurement anomaly/glitch during the test.
Amir doesn't stay with the speaker (I wouldn't want to endure that either ) for most of the testing, so he probably didn't notice/hear it.

Dave.

 

[MattHooper]

Maybe I missed it, but what size woofer is being used--the 5,5" W15 series or the 6.5" W18? Just to keep the price in perspective, the venerable Joseph Audio Pulsar monitor uses the same tweeter and perhaps the same woofer (theirs is the Excel W15), and it goes for over $7,000/pr, albeit with a more elaborate cabinet. NRC measurements for the Pulsar are here: https://www.soundstagenetwork.com/i...&catid=77:loudspeaker-measurements&Itemid=153 I've built a number of speakers based on the Excel drivers, and it's pretty easy to obtain a flat response if that's what you're after.

Interesting to see you mention the Joseph Audio Pulsar, Dennis. As someone who likes Joseph Audio speakers (I own the Joseph Audio floor standing Perspectives) the Verdant speaker immediately reminded me of the Pulsar in it's use of soft dome tweeter with the distinctive-looking SEAS woofer.

Amirm mentioned that, frequency response deviation aside, the Verdant speakers sounded "clean." That happens to be my overriding impression of the Joseph speakers as well (and one mentioned over and over in reviews and user reports). The sound seems particularly free of grit or hash - just super smooth.

I've wondered what to attribute this to. I notice the waterfall - cumulative spectral decay - plot of the Perspective/Pulsars from Stereophile look very clean so it seems intuitive to think that explains things. Adding to that, I used to own (long closed down) Hales Transcendence 5 speakers and currently own the monitor version of those speakers (for home theater), and one of the things that attracted me to them was the same as for the JA speakers: an overt "clean/hash-free" and smooth character to the sound. A defining characteristic. The Stereophile measurements those speakers also show a very clean waterfall plot.

The intuition here for me is to ascribe this "clean" character to the SEAS drivers.

But I'm no speaker designer and I know it's easy for the uninformed to fall in to false inferences. I also seem to remember someone of repute (Floyd Toole?) saying one can't draw much from waterfall plots. And of course a design depends on overall execution, which again makes me greatly hesitate to ascribe a "sound" to "drivers" (many subjectivist audiophiles fall in to a particular form of this fallacy - e.g. "metal drivers sound metallic, plastic like plastic, pulp drivers sound papery"...etc).

Thoughts?

 

[Dennis Murphy]

Interesting to see you mention the Joseph Audio Pulsar, Dennis. As someone who likes Joseph Audio speakers (I own the Joseph Audio floor standing Perspectives) the Verdant speaker immediately reminded me of the Pulsar in it's use of soft dome tweeter with the distinctive-looking SEAS woofer.

Amirm mentioned that, frequency response deviation aside, the Verdant speakers sounded "clean." That happens to be my overriding impression of the Joseph speakers as well (and one mentioned over and over in reviews and user reports). The sound seems particularly free of grit or hash - just super smooth.

I've wondered what to attribute this to. I notice the waterfall - cumulative spectral decay - plot of the Perspective/Pulsars from Stereophile look very clean so it seems intuitive to think that explains things. Adding to that, I used to own (long closed down) Hales Transcendence 5 speakers and currently own the monitor version of those speakers (for home theater), and one of the things that attracted me to them was the same as for the JA speakers: an overt "clean/hash-free" and smooth character to the sound. A defining characteristic. The Stereophile measurements those speakers also show a very clean waterfall plot.

The intuition here for me is to ascribe this "clean" character to the SEAS drivers.

But I'm no speaker designer and I know it's easy for the uninformed to fall in to false inferences. I also seem to remember someone of repute (Floyd Toole?) saying one can't draw much from waterfall plots. And of course a design depends on overall execution, which again makes me greatly hesitate to ascribe a "sound" to "drivers" (many subjectivist audiophiles fall in to a particular form of this fallacy - e.g. "metal drivers sound metallic, plastic like plastic, pulp drivers sound papery"...etc).

Thoughts?

A few thoughts. They're just very well engineered products (smooth response in the critical 1 kHz area for the woofer, smooth and very low distortion tweeter). And crossovers are very easy to implement. For the woofer, you just need a single series inductor and a trap circuit to damp down the single metal ringing mode in the mid-highs. Some times that only requires a capacitor and small inductor. And the tweeter is also a snap to cross smoothly. I don't want to get into the issue of whether the stiff magnesium woofer cone has more detail because it's "faster." But you can see from the FR curve or a waterfall that the woofer has very little stored energy. The original Pulsar had a much more complex "infinite slope" crossover that relied on interactions between adjacent inductors to produce very high order slopes. I talked to the designer last year at a trade show, and that's no longer the case, although I don't know any details about the current crossover. It could be that the increased emphasis on controlled directivity motivated the change. The original Pulsar does have an off-axis flare in the lower treble, but it couldn't be causing too many problems given how good those speakers sound. Finally, the Pulsar cabinet is extremely inert (it better be for $7.000/pair), and that may also be contributing to their clarity

 

[amirm]

Yeah, I would agree. Some sort of measurement anomaly/glitch during the test.
Amir doesn't stay with the speaker (I wouldn't want to endure that either ) for most of the testing, so he probably didn't notice/hear it.

Dave.

I stay during distortion tests but have earphones on so don't notice a lot through them.

 

[MattHooper]

A few thoughts. They're just very well engineered products (smooth response in the critical 1 kHz area for the woofer, smooth and very low distortion tweeter). And crossovers are very easy to implement. For the woofer, you just need a single series inductor and a trap circuit to damp down the single metal ringing mode in the mid-highs. Some times that only requires a capacitor and small inductor. And the tweeter is also a snap to cross smoothly. I don't want to get into the issue of whether the stiff magnesium woofer cone has more detail because it's "faster." But you can see from the FR curve or a waterfall that the woofer has very little stored energy. The original Pulsar had a much more complex "infinite slope" crossover that relied on interactions between adjacent inductors to produce very high order slopes. I talked to the designer last year at a trade show, and that's no longer the case, although I don't know any details about the current crossover. It could be that the increased emphasis on controlled directivity motivated the change. The original Pulsar does have an off-axis flare in the lower treble, but it couldn't be causing too many problems given how good those speakers sound. Finally, the Pulsar cabinet is extremely inert (it better be for $7.000/pair), and that may also be contributing to their clarity

Thanks for the response Dennis.

I know that the crossover in the JA speakers has been evolving, but wasn't sure if it had actually moved out of the Infinite Slope design (which is their calling card, at least ostensibly). In any case, good reviews and user reports for the updated models with new SEAS graphene drivers (though unlikely to be due to the graphene coating).

 

[Rick Sykora]

Thought it might be worth directly stating, but the Pulsar is NLA and its successor is $9000 list.

Still has infinite slopes though!

 

[Dennis Murphy]

Thought it might be worth directly stating, but the Pulsar is NLA and its successor is $9000 list.

Still has infinite slopes though!

So what's $2,000 between audiophiles. Just sign your stimulus check over to Joseph Audio. Their use of the "infinite slope" terminology is pretty confusing. If you look at Stereophile's frequency response measurement, the acoustic slopes are significantly less than 4th order (24 dB per octave). https://www.stereophile.com/content/joseph-audio-pulsar-loudspeaker-measurements. So I dunno what the story is.

 

[Rick Sykora]

So what's $2,000 between audiophiles. Just sign your stimulus check over to Joseph Audio. Their use of the "infinite slope" terminology is pretty confusing. If you look at Stereophile's frequency response measurement, the acoustic slopes are significantly less than 4th order (24 dB per octave). https://www.stereophile.com/content/joseph-audio-pulsar-loudspeaker-measurements. So I dunno what the story is.

Between us audiophiles, it is $2000.

Between my wife and I, a $9000 pair of speakers is:

1. Why are these better than what you already have?
2. What about the nice getaway she had planned?
3. Will you be able get rid of those subwoofers now?

 

[Selah Audio]

Between us audiophiles, it is $2000.

Between my wife and I, a $9000 pair of speakers is:

1. Why are these better than what you already have?
2. What about the nice getaway she had planned?
3. Will you be able get rid of those subwoofers now?

Tell her there are worse addictions that you could have.

 

[q3cpma]

Tell her there are worse addictions that you could have.

Better luck trying to convince someone that the grass really isn't greener on the other side of the fence.

 

[MattHooper]

Between us audiophiles, it is $2000.

Between my wife and I, a $9000 pair of speakers is:

1. Why are these better than what you already have?
2. What about the nice getaway she had planned?
3. Will you be able get rid of those subwoofers now?

Oh, yes, the audiophile's dilemma - the wife!

As I get older this gets easier, as I've slowly and stealthily accrued more (and more valuable) gear, so these days I'm generally in a position to sell-something-to-get-something. So the financial pain isn't too great. And my wife is pretty understanding, she knows I sock away bits of money through the year for a new toy down the line. But these days, as long as I sell a pair of speakers in order to bring a new pair in to the house, the friction factor is low.

 

[witwald]

Good bass-mid driver? That bloody thing takes off at 8 kHz (I had to check as I didn't know the exact model number) -
http://www.seas.no/index.php?option...id=351:e0015-08s-w15cy001&catid=49&Itemid=359

With those significant resonance peaks in the natural unfiltered response of this driver, how can this driver be considered as a worthwhile candidate for a high-quality loudspeaker system when it so clearly has such major structural problems? It would seem that the BBC research of last century into the importance of controlling driver resonances has not been heeded in the design of this particular driver.

 

[Shazb0t]

With those significant resonance peaks in the natural unfiltered response of this driver, how can this driver be considered as a worthwhile candidate for a high-quality loudspeaker system when it so clearly has such major structural problems? It would seem that the BBC research of last century into the importance of controlling driver resonances has not been heeded in the design of this particular driver.

View attachment 58176

Because they are way past where sane people would crossover to a tweeter.

 

[witwald]

But won't those 10-dB or so resonances continue to ring and add their response to the sound even though they are attenuated below the crossover frequency? Would it not be even more sane to just not use this particular driver because of its fundamental vibroacoustic flaws?