SET amp owners thread

[morricab]

I have 4 systems, and with Zu, it's the one I analyze the sound the least after listening. I simply don't think it needs any improvement.

It's amazing how the Zu speaker and the Audion SET just fuse together in perfect union and convey every bit of emotion of the artists. Listening to King Curtis, Aretha, Mike Bloomfield, Albert King, and other artists that play in a more emotional rather than cerebral style, it's all dropped-jaw and goosebumps. Kind of like a Porsche Boxster on a mountain road - just perfect for what it does.

I don't give a damn that something may be a bit more transparent or some well-marketed box speaker may have more bass wallop. I would never trade the Zu for any box speaker.

The zu is a “box” speaker though, right? I mean only the super tweeter is a horn I think. Not that it really matters...

 

[Legolas]

The Zu has a down firing bass driver and the rest of the cabinet seems sealed, no ports. Is that correct?


My Zingali client name Evo 1.2s also have a down firing bass port with the mid-upper frequency horn in the same cabinet space.
My concern with any 'box' speaker is cabinet interaction or coloration, it is pretty difficult to avoid at higher volumes. So we can have a huge range of design methods to avoid that, such as composite materials that fight vibration, curved panels, aluminium casting (Magico), complex internal bracing. At the extreme end of how not to make a speaker IMO, look at the Audio Note AN-Es, no internal bracing, thin plywood cabinet etc. The whole contruction in that case becomes part of the sound (in a negative manner).

 

[spiritofmusic]

Astro, well my model of Zu uses self powered semi active down firing subs that pass to full range drivers at 40Hz, thence to semi horn loaded tweeters at 11kHz. Sealed box, non ported.

 

[Legolas]

Are you sure they hand over at 40hz? That seems very low.

 

[spiritofmusic]

It's prob more like 50Hz
But the design is full range drivers to cover the main range of human voice 40Hz-11kHz
Of course this introduces it's own set of compromises incl some tendency to shout from 8-9kHz up, and a slight chestiness in the lower mids/upper bass. Full range drivers are asked to do a lot, and the Zu ones are nowhere near as sophisticated as, say, the BD drivers in Pnoe horns, or even those in Voxativ 9.87's.

 

[Legolas]

Interesting, thanks for that extra info. I respect any speaker designer trying to get maximum efficiency and a linear FR, as both don't seem to generally lend themselves to that. It is all too 'easy' to have a 4 or 5 multiway speaker tower that has dynamic capabilities and flat FR but is not very efficient.

IMO the seemly increasing invested in tube amps, particularly SETs will drive more R+D and advances in efficient speaker design.

 

[spiritofmusic]

I really can't see it Astro. The market is in big multi driver spkrs, heavyweight amps. Tubes, horns, high efficiency friendly drivers, these are blips in the grand scheme of things.

When I see these big signature multi driver towers w their brutal impedance swings and demands for iron grip amps, dominate the high high end, and then listen to single driver horns able to fill 20,000 cub ft off 1.46A, I do ponder...

 

[caesar]

The zu is a “box” speaker though, right? I mean only the super tweeter is a horn I think. Not that it really matters...

Yes, good point! I never thought about it, but just enjoyed the music. ...

now that I think about it, as I never really liked box speakers, the reason for that is that it’s a single driver vs. a mush mash of drivers kludged together.

Come to think of it, I also really liked the voxativ at the last rmaf also.

 

[caesar]

Is Zu considered a ported or a sealed bass design? Does anyone know? Thanks

 

[jeff1225]

Is Zu considered a ported or a sealed bass design? Does anyone know? Thanks

Zu makes models that are ported and have a built in powered subwoofer in a sealed cabinet.

 

[DaveC]

It's prob more like 50Hz
But the design is full range drivers to cover the main range of human voice 40Hz-11kHz
Of course this introduces it's own set of compromises incl some tendency to shout from 8-9kHz up, and a slight chestiness in the lower mids/upper bass. Full range drivers are asked to do a lot, and the Zu ones are nowhere near as sophisticated as, say, the BD drivers in Pnoe horns, or even those in Voxativ 9.87's.

I'm a big fan of full range drivers but "sophisticated" is not a term I'd use.

Anyone mechanically inclined can start making them with a paper cutting machine and very basic metalworking tools. It's an art/craft for sure, but definitely not rocket science.

AFAIK, Lowther is the original of that type of driver and AER got into the biz by modifying them, then Voxativ copied AER... pretty much literally.

I also think the biggest issue with them is playing complicated music, traditional multi-way speakers can do it better.

 

[spiritofmusic]

No disrespect to the Zu naysayers, but before we diss their full range drivers, we should read a bit more what goes into them.

Chief designer Sean Casey has taken the "simple and unsophisticated" concept and maxxed it with a lot if care and attention incl dopings and treatments. This has enabled him to produce a full range paper cone that is indeed "somewhat" not simple and not unsophisticated. He's worked hard at ameliorating shortcomings like shoutiness at higher frequencies, more even low frequency response, indeed more speed and linearity over the 2.5 octaves that the full range drivers cover.

Otoh, Sean is firmly in the camp of "go simple enough, but not too simple". So, while his drivers are taken beyong simple, he's still a fan of the concept that eliminating crossovers, keeping efficiency high, having as sweet and smooth an impedance curve as possible, allows a particular take on getting to the heart of the musical message.

So please, can we get past the urban myth that Zu is just a rock speaker, or a party speaker, or that full range drivers are by definition unsophisticated and an easy option. I think the fact that one of the top half dozen spkrs in the world, the 118dB eff Pnoes horns, uses the exemplary full range drivers BD, defies the criticism of this topology as some sort of inferior option.

 

[Audiophile Bill]

No disrespect to the Zu naysayers, but before we diss their full range drivers, we should read a bit more what goes into them.

Chief designer Sean Casey has taken the "simple and unsophisticated" concept and maxxed it with a lot if care and attention incl dopings and treatments. This has enabled him to produce a full range paper cone that is indeed "somewhat" not simple and not unsophisticated. He's worked hard at ameliorating shortcomings like shoutiness at higher frequencies, more even low frequency response, indeed more speed and linearity over the 2.5 octaves that the full range drivers cover.

Otoh, Sean is firmly in the camp of "go simple enough, but not too simple". So, while his drivers are taken beyong simple, he's still a fan of the concept that eliminating crossovers, keeping efficiency high, having as sweet and smooth an impedance curve as possible, allows a particular take on getting to the heart of the musical message.

So please, can we get past the urban myth that Zu is just a rock speaker, or a party speaker, or that full range drivers are by definition unsophisticated and an easy option. I think the fact that one of the top half dozen spkrs in the world, the 118dB eff Pnoes horns, uses the exemplary full range drivers BD, defies the criticism of this topology as some sort of inferior option.

Marc - part of the issue is the marketing strategy of Zu. They usually present at shows using a mixing desk and 2 decks playing party music. The brand is presented that way hence the public view them that way.

In terms of the quality of Zu speaker drivers I can’t comment cos not heard them properly to say.

 

[DaveC]

No disrespect to the Zu naysayers, but before we diss their full range drivers, we should read a bit more what goes into them.

Chief designer Sean Casey has taken the "simple and unsophisticated" concept and maxxed it with a lot if care and attention incl dopings and treatments. This has enabled him to produce a full range paper cone that is indeed "somewhat" not simple and not unsophisticated. He's worked hard at ameliorating shortcomings like shoutiness at higher frequencies, more even low frequency response, indeed more speed and linearity over the 2.5 octaves that the full range drivers cover.

Otoh, Sean is firmly in the camp of "go simple enough, but not too simple". So, while his drivers are taken beyong simple, he's still a fan of the concept that eliminating crossovers, keeping efficiency high, having as sweet and smooth an impedance curve as possible, allows a particular take on getting to the heart of the musical message.

So please, can we get past the urban myth that Zu is just a rock speaker, or a party speaker, or that full range drivers are by definition unsophisticated and an easy option. I think the fact that one of the top half dozen spkrs in the world, the 118dB eff Pnoes horns, uses the exemplary full range drivers BD, defies the criticism of this topology as some sort of inferior option.

Eh, speakers are all simple devices.

You do know that my speakers are based on a horn loaded full range driver w/ woofer and supertweeter, right? Not too far off the Zu concept...

 

[Exlibris]

Thomas Mayer 45/2A3.
Best,
Dave

 

[bonzo75]

Thomas Mayer 45/2A3.
Best,
Dave

Wow cool. This is with your AN E?

 

[bonzo75]

So the same amp allows you to swap 45 and 2a3?

 

[Exlibris]

That's correct, I still have the AN Es and the amp can take both 45 and 2a3. You can't really see it in this photo, but behind and to the inside of each output tube there is a toggle switch to make the selection between 45 and 2a3. I'm currently using NOS Cunningham CX-345, globe shape.

 

[Exlibris]

Here's the amp in my system.

 

[Exlibris]

The output tubes in that photo are Sophia Electric 300B 2.5v (a drop-in replacement for 2A3s).