Treehaus Audiolab

[Ron Resnick]

An interesting -- and interesting looking -- loudspeaker at AXPONA 2023 was the Treehaus Audiolab open baffle, field coil full-range driver loudspeaker.




This system -- with Treehaus electronics -- garnered very positive reviews.

After hearing the small Wolf von Langa loudspeakers produce a sound I have never heard from such small boxes I have a new appreciation for anything and everything field coil!

Treehaus Audiolab Field Coil Speakers

Treehaus Audiolab Field Coil Speakers, Tube Amplifiers, and Preamplifiers

www.treehausaudiolab.com

 

[bonzo75]

Looks great

 

[dcathro]

@Parsons has a set of the Treehaus speakers:

https://www.whatsbestforum.com/threads/solid-state-amp-to-drive-field-coil-woofers-thoughts.31339/

 

[Alrainbow]

I’ve heard them 3 times before axpona
Was not a sound I liked until this year , it was good.
they sound like pure audio project he also uses a field coil as an option. Pure Audios setup at axpona was good I plan to do a simple post and pics of his.
these look really cool. Always look great past and present.
I think the cross over and amp used is really fussy on open baffle. harry at VPI had pure audio speakers on a full pass labs and played tape it was really nice.

 

[spiritofmusic]

One of the few spkrs I'd consider as a genuine alternative to my Zus, especially because I believe the Treehaus are also c.100 dB/1m efficiency.
The combination of open baffle, field coil, what I know is an amazing main driver, and unique aesthetics, really appeal.
Now, all I would need with these are Thundersnow's Nat Audio Magma Evo HPS amps with the Eimac 450 tubes!

 

[Alrainbow]

wow did not know this. I don’t think pure audio is that eff . I remember how much better it was when the maker installed the field coil for a demo. The ones at axpona were not field coil but were very good for me

 

[Parsons]

Yeah, I actually own 2.5 pairs (2 stereo pairs and 1 mono!) from Treehaus now. In full disclosure, I have worked with Rich and Treehaus so long now in his designing, building, and delivering the speakers, amps and pre-amps he's built for me...I definitely consider him a friend at this point. To be super clear I have nothing to do with Treehaus from a business nor financial perspective, but as a consumer I am a very, very big fan of his work and I continue to commission pieces from him. While I've met a number of outstanding humans in the audio industry over my years (decades), Rich is simply a great person on top of being a super talented designer and builder. That aside, I have a lot of Treehaus equipment in a number of my systems because I'm incredibly happy with the sound of his systems and the approach he takes with the technical designs, and I wouldn't own any of it if that weren't the case.

I was fortunate enough to make Axpona this year which was my first show I'd ever attended. Because Rich knew I was attending he asked me if I wanted to spin some tunes in his room (we both also have a pretty similar taste in music as it turns out). That was super fun and I'm glad I got to hang out with him and meet attendees with similar tastes. I may have seen some of you either in his room or in my wanderings around the show Saturday and Sunday. I had a blast and Axpona will be something I definitely do again in future years. While shows are not the best way to hear some of that equipment and systems, there is a bit of playing field leveling that is kind of cool and you sure can hear a lot of systems back-to-back.

I definitely wasn't sure what to expect in those small rooms with Rich's open baffle speakers...I have my sets of his speakers in pretty big rooms, and had never heard them in a hotel-sized room. After the first couple of songs I told Rich I was pretty shocked at the sound he produced at the show...it was really a strong showing, especially given the limits of the space. I think there's generally a biased assumption (which I admit I had) that open baffles need massive space to produce great sound, and I think if you heard his set-up in that room, you would have scratched your head a little too...it really sounded amazing. In the couple hours I spent in the room over a the weekend, a ton of listeners seemed to share the positive surprise and many made comments to that effect. He had them pretty far back (for my bias) into the corners, yet it still sounded big and full like I know them to sound. I still don't think this is the ideal positioning for speakers of this design, but certainly proved these things to be a lot more flexible than I guessed. My main listening room is considerably larger, and not surprisingly my system is able to produce an even more impressive sound field, but Rich did a nice job showing what his system is capable of within those limits.

As for Treehaus speakers and their design (both technical and aesthetic)...here's how I ended up with these speakers (and so many of them).

I haven't heard everything in the high-efficiency space, but I'm very biased to the high-efficiency design at this point in my journey. I still own three sets of vintage Altecs (Valencias and 14s, both with custom crossovers, and a pair of custom baffled 604es with Goto super tweeters and custom crossovers), and I still own 2 pairs of Zus (and owned 2 other pairs of Zus I've since sold). I spent some years travelling to various showrooms around the country to spend time with Shindo's, Auditorium 23 range (multiple times and many in the range), Classic Audio Loudspeaker, big JBLs, a few others I'm forgetting. I loved some, had mixed feelings on many, flat out disappointment with others. As many of you may also attest, the showroom setups in some otherwise really high-end dealers can be spectacularly mediocre. I wonder if some dealers know what a great or even good system sounds like. Unfortunate because I still think the audio dealers to be an important part of this hobby. I also think some of these speakers just aren't that amazing, perhaps. But I digress.

An any rate, in those years I became super interested in field coils. While I don't think they by themselves make a speaker (I've heard some mediocre field coil drivers), a well-executed field coil with the proper power supply will almost certainly be able to do things fixed magnet cannot (some will disagree, but there is a very good reason some very strong manufacturers bother to mess with top field coils in their upper level speakers). However, the cabinet design will also greatly affect the impact of the field coil drivers--I heard two different cabinet speakers in the same room with identical field coil drivers and supporting audio system, and one wowed me and the other was just ok. The cabinet design matters a lot too, obviously.

This journey also biased me toward full range drivers with no crossovers as the basis for my favorite speakers...but almost always with augmentation above and sometimes below (super tweeters and sometimes woofers). The speed, immediacy, punch, transparency and midrange just feels next level to me, and when you combine field-coil in the mix, it's another level still. It removes the "hifi" sound that I just can't wrap my head around how people could truly enjoy. It's all-day/all-night listening emotion when done right.

I had never considered open baffle until I heard the Treehaus speakers...I had assumed (for years) that I was a "horn guy." Open baffle is not a DIY gimmick as I perhaps was thinking from my forum meandering the past.

At any rate, I would strongly, strongly encourage anyone in the hobby to make a point to listen to some really well-implemented full-range (no crossover), high-efficiency field-coil-based speakers. Treehaus speakers are certainly ones you should hear in this design camp. When paired with the proper SET amplification and top-end sources, the emotional sound that can be created is really hard to beat. Treehaus speakers sound amazing with a variety of amps (you will hear all the differences in your amps with these speakers), but there is a reason Rich is focused on his 300B SET design for his current amp offering, and I agree with that decision. Stunning combo.

 

[spiritofmusic]

Really nice precis, Parsons.
As you know I'm a Zu man, running the Defs 4 w Lundahls to high pass filters, soon to be installed custom fit out to my sub amps, and critically now augmented with Arya Audio Airblades Hype SE.
I am seriously considering the Zu Definitions 6, but have a taste for field coils, having heard Audiophile Bills amazing bespoke horns and DaVa cart, and really liking the Von Langa Sons.
I also have deep admiration for the ideas on the Japanese Maxonic field coil spkrs.
Bills horns are semi open baffles, and my TT maker runs a very tasty set of open baffles.
And I can't look past the drop dead amazing aesthetics of these Treehaus'.
Your summary is certainly food for thought.

 

[Parsons]

I am still a huge fan of my little Soul Supremes and happy to report that I have them back after loaning them to a friend, running as a little bedroom system and performing marvelously with a PX4 SET amp. I have yet to hear any Definitions but would still love to...I have no doubt the new ones will be impressive, as the reviews of yours are already so strong. My latest Druids didn't quite do it for me (especially as my room size grew 3x in the new house), but I realize the Defs are another speaker altogether. I was disappointed that the Def 6s weren't at Axpona, but I heard Sean was there (would have liked to have met him in person), perhaps with his new bookshelf speakers (which I never managed to find unfortunately).

If you can get to the east coast/NYC area I encourage you to make the short trip to Treehaus' demo space in CT, and if in the Michigan area, assuming he is still showing them, you should also consider hearing John's Classic Audio Loudspeaker Hartsfields with the field coils. Those would both be interesting comparisons for the sound I presume you love, and give you a good taste of what field coil is about as well.

 

[spiritofmusic]

Parsons, my main misgivings at this point are.
1...the DSP aspect of sub woofer, blending in likely a SS amp with SET one to the main drivers.
2...finding the right SET to make these spkrs come alive in my 6000 cub ft room.
...even on my 101dB efficient Zus, 50W seems to be the minimum needed, and there are very few SETs that powerful.

 

[Alrainbow]

Not to digress but have either of you guys heard any pure audio Speakers?? it’s an obvious given treehause looks amazing so just in looks they are a winner.
I too thought open baffle was a gimmic of sorts. But have been proven wrong
I always thought it was tree house lol.

 

[Parsons]

I was skeptical about the dsp at first, too, until i heard it and played around w/ it for a while. First and foremost it's just a basic digital crossover for the woofers. You don't have to use the room correction, but I think it helped tighten things up from there with the correction. Rich helped me set it up initially when he delivered the speakers. I swapped other components over the next year or so, and felt I wanted to mess around with it, and it was pretty fun and interesting and not that hard to experiment with on my own (I had the software on my mac and already owned the mic, and I think Rich walked me through a couple pointers over the phone). When he brought my new amps on a later purchase, I asked him to set up the dsp again, and where we settled wasn't far off from where I ended up when i did it by myself (we also kept all my original settings in two presets so I could switch back and forth---I stuck with his). I ended up with a Cary amp to drive the woofers. I think Rich was driving them with some digital monoblocks at Axpona. The bass sounded great there too. I'm super happy with it as a solution and actually sold my Zu sub (which I loved) to another buddy as I didn't feel it was necessary at all once the Treehaus speakers were in place. I should note my woofers are field coils which I'm not sure if he is using on his builds any longer, although I'm very happy with them and would use them again.

As for the amp to drive the mains, I'm running a 4 box version of Rich's 300B SET amp he had at Axpona. At ~6 wpc it plays so loud and clean that I don't have any desire for more power. I used Atma-Sphere M60 monos for a bit...way more than enough and even ran those with half the tubes at half the output for awhile. I have run the Treehaus mains with my Cary as well just for fun. Still sounded great, but the SETs seem to be where I've settled and particular the 300B (with the new WEs that ship with his amps now), and a PX4 amp that also made its way via Treehaus builds. Oh, and this may sound crazy, but I actually ran even my big Treehaus speakers for about 9 months with a 71a two box amp (guess from whom!)...I think that was probably only pushing 3/4 (0.75) wpc. It played crazy loud even with that, but that's pushing that little amp to some limits no doubt.

I don't actually know what the efficiency of the Treehaus speakers are exactly...perhaps a few db more efficient than the Defs?

I'm trying to do the reverse math on 6000 cu ft. OK, I'm just a tad smaller than yours at 19' x 36' x 8.5'.

In short, I think any well-executed and clean SET, particularly in 300B, should be plenty even for a room your size.

 

[Parsons]

Not to digress but have either of you guys heard any pure audio Speakers?? it’s an obvious given treehause looks amazing so just in looks they are a winner.
I too thought open baffle was a gimmic of sorts. But have been proven wrong
I always thought it was tree house lol.

I haven't but I think they look interesting, and I would like to hear some. They don't appear to be using field coils, perhaps to stay at some particular price points (I know Voxativ makes some pretty serious field coils, and that seems to be the full-range maker they are using).

 

[Alrainbow]

What dsp software was he using ? it’s did sound good and I went back a few times too. Really great looking stuff for sure.

 

[Parsons]

He's using Room Eq Wizard (REW) for making the measurements/curves, then it gets loaded to a MiniDSP device which sits between the pre-amp out and woofer amp inputs. In fact, I just remembered that in my first speakers from him (with traditional woofers), he used a MiniDSP device that had an amp built in to drive the woofers...a nice solution that sounded great. This thread had me racking my brain wondering why I couldn't remember why I wasn't playing with the woofer amps with my first set of Treehaus speakers...he built the amp into the DSP solution.

 

[Treehaus Audiolab]

"Speak of the devil and he is sure to appear.."

Hi Everyone! Thank you Ron for posting up about my speakers and amplification products.There has been a lot of positive press and talk. (Dave McNair just did an in depth review over on Tracking Angle). The design ethos around here is to produce great, realistic sound that can provide deep emotive experience for those listening. We don't focus on numbers, or specs. That isn't an excuse or crutch, it is simply a product of hearing so many things that meet a variety of specs and benchmarks and yet the sound ends up being a bit soulless. The products should also have solid industrial design behind them, so they can be featured in the living room and not only hidden away in listening spaces. I'm a big fan of the MCM work of George Nakashima (clearly)

To achieve great sound, natural materials are used when possible, and celebrate the imperfection. The live edge not only adds visual appeal and a bit of sculpture, but it also is a great way to randomly diffract waves off the edge of the baffle. The driver cones, also being handmade, are not "perfect." You will not find carbon fiber or diamond here. If you think about great sound sources.. vocal cords, string instruments, pianos, etc, they are not "perfect" designs made to scientific tolerances.

The Treehaus Audiolab gear is also voiced and tested with regular music, and you will find at shows, audiophile "cheater" tracks are avoided. I am a personal fan of New Wave and contemporary indie. Despite the low wattage SET amps and full range drivers they need to play Nine Inch Nails, and be able to execute any Radiohead/ Thom Yorke track like a star athlete. Given their design, they also of course do the things well you would expect them to: Jazz.. female vocals, etc. I tend to try to find the stuff they shouldn't do well..

I'd also state as part of the philosophy here that Treehaus Audiolab products produce great sound to me, our customers, and many who have heard our stuff on the show circuit. They are a great "answer" but they are NOT the ONLY "answer". If high tech speakers and electronics and big wattage numbers are what takes you a place of audio nirvana, I think that is fantastic and I can appreciate that. There is no right answer in audio, it is what gives you the experience you are looking for in listening that matters.

To touch on the products in detail:

The speakers are open baffle, using live edge wood for the main baffle, with hard maple sidewalls and legs. The core full-range drivers are made by Oleg Rullit in Germany. They are based on vintage Telefunken/ Klangfilm cores that he completely rebuilds with extremely lightweight paper cones, deerskin leather surrounds, and rewound coils. These drivers are very much full range, they go over 15K, and start to roll off gently below 90hz or so. There is no crossover, etc on the full range, it is direct to the amplifier. Very pure.

The super tweeter is crossed over (1st order with an attenuator) over 15K, and I usually have it turned down quite a bit. It's there less for frequency extension, and more for adding a touch more realism to metallic instruments, such as cymbals. On the other end of the frequency spectrum, the woofer is adding some additional foundation in the last octave. I found in the development of these speakers, that given they are open baffle, and room effects bass response and quality are so pronounced in any speaker, that having DSP with separate amplification allowed for a very easy way to get great bass in any room. It uses REW to make the curves, and an included miniDSP to execute it all. Bi-amping the speakers also allows for the ultra-efficient full range driver to do its thing with lower powered SET amps, and then use solid sate for the woofer where that technology better shines. Because its crossed over so low, its more like mixing in a subwoofer into a system than trying to cross over 2 different sounding sources within a more critical listening frequency range. (a very easy to mix in subwoofer because it is also open baffle, in the same enclosure, rather than trying to mix a sealed woofer with an open baffle)

The field coil voltage, being adjustable, allows a bit of tuning of the sound. Adding in the DSP as well, and it gives enough flexibility to dial in the speaker to the room, the electronics ahead of it, and most importantly, the listener preferences. It may seem complicated at first but in reality, a few hours of setup and tweaking and these things quickly dial into the room (rather than some other speakers where you end up moving them all over the place for subtle changes that may or not be an improvement)

Each speaker is made to order, and there are options on quality of field coil driver and wood choices. The wood can affect the sound of course, so I stick to offerings that are medium density hardwoods (walnut, elm, etc).

On the amplification side, the designs are strongly influenced by Susumu Sakuma and early Western Electric. Lots of transformers in the signal, no capacitors. All the signal transformers use Finemet cores, and are made for Treehaus Audiolab in Japan. (by the builders who were originally at Noguchi) In testing and benchmarking MANY transformers, I found Finemet to be excellent at resolving detail, with great tone and liquidity, without any harshness or astringent nature.

The 300B amplifier using a 10Y/801 interstage transformer driving a 300B. The power supply is separate to keep noise (electrical and mechanical) from the amplification circuit. The power supply is TV damper rectified, and the nitty gritty of it is thoroughly modern (constant current source, Coleman filament regulators, etc)

The preamplifier is also heavy on the use of transformers: transformer based volume control, a 4P1L that is triode strapped and running filament bias, and custom output transformers. Basically a mini-SET amp.

Given the strong affinity for Finemet iron; I also make an MC SUT. 3 Ratios, and the cores I dip in Urushi lacquer, wrap in Kimono silk, and then pack in copper boxes.

I do think it takes hearing the speakers in person to realize what they are capable of. At first, people see the live edge wood, and what appear to be a random placement of drivers, some low-powered tube amplifiers attached, and think it is a bit of a gimmick. The reality is the design is carefully considered, from the driver placement, their relation to each other on the baffle, the shape and construction of the sidewalls, etc. It is what transforms an open baffle into a serious speaker.

Thank you for having me here; I deeply love music and audio.. whether is my own product or something else. There are so many great ways to reproduce music. It's about enjoyment; it should never be stressful.

 

[Treehaus Audiolab]

Thank you @Parsons for writing all you did about your setups and the kind words. That basement setup is absolutely killer there.

Alrainbow: I use MiniDSP for the DSP/ EQ and REW for doing the measurements. They are both great pieces of software and easy to use, with tons of support in the greater audio community.

Open baffle is definitely having a renaissance with Pure Audio Project, Spatial, and others. Field coil as well with Songer, Wolf von Langa, Classic Audio, and some of the various speakers Voxactiv drivers find their way into. (lets also not forget Masonic, WIP, and Feastrix in Japan)

Spiritofmusic: I sort of touched on it on my previous post, but blending the woofer and the field coil full range is pretty easy and fluid on these speakers, primarily because we are doing it so low in the frequency spectrum. Ive tried bi amping more "traditional" speakers where that crossover point is 300hz (approx) and it can be very hard to blend different types of amps once you get up into that range. Also, as mentioned, because it's an open baffle woofer on the same enclosure as the open baffle full range driver, they are sonically closer and easier to synergize than a traditional ported speaker and sealed subwoofer in its own box.

 

[christoph]

"Speak of the devil and he is sure to appear.."

Hi Everyone! Thank you Ron for posting up about my speakers and amplification products.There has been a lot of positive press and talk. (Dave McNair just did an in depth review over on Tracking Angle). The design ethos around here is to produce great, realistic sound that can provide deep emotive experience for those listening. We don't focus on numbers, or specs. That isn't an excuse or crutch, it is simply a product of hearing so many things that meet a variety of specs and benchmarks and yet the sound ends up being a bit soulless. The products should also have solid industrial design behind them, so they can be featured in the living room and not only hidden away in listening spaces. I'm a big fan of the MCM work of George Nakashima (clearly)

To achieve great sound, natural materials are used when possible, and celebrate the imperfection. The live edge not only adds visual appeal and a bit of sculpture, but it also is a great way to randomly diffract waves off the edge of the baffle. The driver cones, also being handmade, are not "perfect." You will not find carbon fiber or diamond here. If you think about great sound sources.. vocal cords, string instruments, pianos, etc, they are not "perfect" designs made to scientific tolerances.

The Treehaus Audiolab gear is also voiced and tested with regular music, and you will find at shows, audiophile "cheater" tracks are avoided. I am a personal fan of New Wave and contemporary indie. Despite the low wattage SET amps and full range drivers they need to play Nine Inch Nails, and be able to execute any Radiohead/ Thom Yorke track like a star athlete. Given their design, they also of course do the things well you would expect them to: Jazz.. female vocals, etc. I tend to try to find the stuff they shouldn't do well..

I'd also state as part of the philosophy here that Treehaus Audiolab products produce great sound to me, our customers, and many who have heard our stuff on the show circuit. They are a great "answer" but they are NOT the ONLY "answer". If high tech speakers and electronics and big wattage numbers are what takes you a place of audio nirvana, I think that is fantastic and I can appreciate that. There is no right answer in audio, it is what gives you the experience you are looking for in listening that matters.

To touch on the products in detail:

The speakers are open baffle, using live edge wood for the main baffle, with hard maple sidewalls and legs. The core full-range drivers are made by Oleg Rullit in Germany. They are based on vintage Telefunken/ Klangfilm cores that he completely rebuilds with extremely lightweight paper cones, deerskin leather surrounds, and rewound coils. These drivers are very much full range, they go over 15K, and start to roll off gently below 90hz or so. There is no crossover, etc on the full range, it is direct to the amplifier. Very pure.

The super tweeter is crossed over (1st order with an attenuator) over 15K, and I usually have it turned down quite a bit. It's there less for frequency extension, and more for adding a touch more realism to metallic instruments, such as cymbals. On the other end of the frequency spectrum, the woofer is adding some additional foundation in the last octave. I found in the development of these speakers, that given they are open baffle, and room effects bass response and quality are so pronounced in any speaker, that having DSP with separate amplification allowed for a very easy way to get great bass in any room. It uses REW to make the curves, and an included miniDSP to execute it all. Bi-amping the speakers also allows for the ultra-efficient full range driver to do its thing with lower powered SET amps, and then use solid sate for the woofer where that technology better shines. Because its crossed over so low, its more like mixing in a subwoofer into a system than trying to cross over 2 different sounding sources within a more critical listening frequency range. (a very easy to mix in subwoofer because it is also open baffle, in the same enclosure, rather than trying to mix a sealed woofer with an open baffle)

The field coil voltage, being adjustable, allows a bit of tuning of the sound. Adding in the DSP as well, and it gives enough flexibility to dial in the speaker to the room, the electronics ahead of it, and most importantly, the listener preferences. It may seem complicated at first but in reality, a few hours of setup and tweaking and these things quickly dial into the room (rather than some other speakers where you end up moving them all over the place for subtle changes that may or not be an improvement)

Each speaker is made to order, and there are options on quality of field coil driver and wood choices. The wood can affect the sound of course, so I stick to offerings that are medium density hardwoods (walnut, elm, etc).

On the amplification side, the designs are strongly influenced by Susumu Sakuma and early Western Electric. Lots of transformers in the signal, no capacitors. All the signal transformers use Finemet cores, and are made for Treehaus Audiolab in Japan. (by the builders who were originally at Noguchi) In testing and benchmarking MANY transformers, I found Finemet to be excellent at resolving detail, with great tone and liquidity, without any harshness or astringent nature.

The 300B amplifier using a 10Y/801 interstage transformer driving a 300B. The power supply is separate to keep noise (electrical and mechanical) from the amplification circuit. The power supply is TV damper rectified, and the nitty gritty of it is thoroughly modern (constant current source, Coleman filament regulators, etc)

The preamplifier is also heavy on the use of transformers: transformer based volume control, a 4P1L that is triode strapped and running filament bias, and custom output transformers. Basically a mini-SET amp.

Given the strong affinity for Finemet iron; I also make an MC SUT. 3 Ratios, and the cores I dip in Urushi lacquer, wrap in Kimono silk, and then pack in copper boxes.

I do think it takes hearing the speakers in person to realize what they are capable of. At first, people see the live edge wood, and what appear to be a random placement of drivers, some low-powered tube amplifiers attached, and think it is a bit of a gimmick. The reality is the design is carefully considered, from the driver placement, their relation to each other on the baffle, the shape and construction of the sidewalls, etc. It is what transforms an open baffle into a serious speaker.

Thank you for having me here; I deeply love music and audio.. whether is my own product or something else. There are so many great ways to reproduce music. It's about enjoyment; it should never be stressful.

Will you and your extremely interesting products also be in Munich this May?

 

[Alrainbow]

And also at capital this year ? they sounded very good at axpona now I’m really looking forward to hearing them more. Your choice of real audio tracks is very nice to read. I never ask rooms
To play crazy stuff but stuff I do know and rock I all most never ask.
using for the most part a single driver is a better way to reproduce music. Most times when I’ve heard this method it always seemed rolled off. Yours are sincerely appreciated good sound quality
Makes the point of single driver very clear

 

[spiritofmusic]

Parsons and Rich, great overviews. I am slightly taken aback that 6.5W can power the Treehaus OBs to fill a room just smaller than mine.
This suggests that if the Treehaus OBs are *genuinely* 102dB/1m efficiency, my Zus aren't 101dB, maybe closer to 97-98dB.
And if this is the case, then a whole bunch of 300B options like the Treehaus SETs, and gear like Audion Golden Dreams opens up as possibilities in my 18x50x9 room.
I'm also liking that Rich is talking about less than stellar audiophile masterings that his spkrs excel at...for me it's critical that these spkrs have to come alive on 70s Miles Davis and Mahavishnu Orchestra, 80s Rush, 90s Marillion and 00s Porcupine Tree and Tool, as well as the Golden Age classical, jazz and classic rock stuff I'd expect any top transducer to be great at.