[kevtn8]

Has anyone ever compared the sound of a directly heated triode SET such as 2A3/45 amp  ( such as Bottlehead Steremour) vs a pseudo (wired) SET such as Decware SuperZen or Rachael with their Omegas?

Basically what I'm curious about is that are DHT SETs automatically superior sounding to their pseudo or wired SETs ( and vice versa) or is there much more to it than this?

What are the pros/cons of each design topology when compared to the other? My guess is that the overall circuit design and execution of the amp is just as important or more, correct?

If anyone can shed some light on this topic , especially in the context of hearing them with Omega speakers that would be really helpful for me and I'm sure lots of other folks as well who are into low power SET pairing with their Omegas or are thinking about it.

[seikosha]

I've got a 2A3 amp using a JE Labs schematic and a Zen and play them on Omega 3XRS's with the RS5 drivers.  They are very close.

A few quick comparisons.

The added power of the 2A3 over the Zen is noticeable.  The 2A3 has better bass than the zen and the highs I feel are preferable too.  Imaging, dimensionality and soundstaging of the amp is top notch as it is on the Zen.  In fact when I received the 2A3 and plugged it in, I thought.  This is it.  Over time though, I found that my listening sessions weren't as long or as enjoyable.  After I got over the added extension at both ends, I realized that in the midrange, the 2A3 just didn't quite have as much of an organic quality as the Zen which just seemed to give a little more body and dimensionality to voices and midrange centric instruments.  Things were just a little more fleshed out with the little Zen.

It's a very close call though and I suspect that if you put ten audiophiles in a room with both amps, they'd be split 50/50.  I also can't help but wonder if I would prefer the 2A3 on a Super Alnico design as apparently that driver is a little more warmer and organic than the RS5.

[Canada Rob]

I haven't heard the new Decware UFO output transformer yet.  It may close the gap on a 2A3 as far as frequency extension goes, as long as it maintains that spooky palpable midrange it's predecessor is famous for.

One of the problems the audio industry has been obsessed with for decades is frequency extension, and it's been at the expense of the all important midrange.  The result has been decades of "HiFi", and not reproduced reality like what I experience in a well designed SET/single driver system.

[seikosha]

I haven't heard the new Decware UFO output transformer yet.  It may close the gap on a 2A3 as far as frequency extension goes, as long as it maintains that spooky palpable midrange it's predecessor is famous for.

Hi CR,

The Zen comparison was done with a UFO model.  I've got a standard Zen as well, the UFO transformers are definitely as step up.

You are right about obsession with frequency extremes.  It's a very easy trap to fall into.

[Canada Rob]

Thanks for that seikosha.  I've had three generations of SE84 and every one has been a step up from it's predesessor, yet when I had each of them, I never craved for more - they were my reference at the time I had them.  If I'd never heard Steve's upgrades, I'd probably still have my original SE84C+.  It was the amp that converted me solidly to tubes, though I still love certain solid state amps.

A UFO Decware is in my sights though. 

[DaveC113]

I've done some comparisons... my DIY EL34 SET amp is anything but typical though. It sounds more solid-state than many SS amps but still has the dimensionality and tone of tubes. In comparison with an Air Tight Preamp + Fi 2A3 monoblocks my EL34 was better in most ways, the owner of the Air Tight/Fi combo sold them and looked at other choices as a result. Speakers used were Lamhorns with AER drivers, possibly the most revealing speakers I've ever heard.

My conclusion is the circuit, including power supply, and parts used are much more important than the output tubes.

[Canada Rob]

My conclusion is the circuit, including power supply, and parts used are much more important than the output tubes.

I totally agree.

[Sense63]

I've done some comparisons... my DIY EL34 SET amp is anything but typical though. It sounds more solid-state than many SS amps but still has the dimensionality and tone of tubes."

Just curious......what DIY EL34 SET amp are you referring to?

Thanks!

[kevtn8]

I've got a 2A3 amp using a JE Labs schematic and a Zen and play them on Omega 3XRS's with the RS5 drivers.  They are very close.

A few quick comparisons.

The added power of the 2A3 over the Zen is noticeable.  The 2A3 has better bass than the zen and the highs I feel are preferable too.  Imaging, dimensionality and soundstaging of the amp is top notch as it is on the Zen.  In fact when I received the 2A3 and plugged it in, I thought.  This is it.  Over time though, I found that my listening sessions weren't as long or as enjoyable.  After I got over the added extension at both ends, I realized that in the midrange, the 2A3 just didn't quite have as much of an organic quality as the Zen which just seemed to give a little more body and dimensionality to voices and midrange centric instruments.  Things were just a little more fleshed out with the little Zen.

It's a very close call though and I suspect that if you put ten audiophiles in a room with both amps, they'd be split 50/50.  I also can't help but wonder if I would prefer the 2A3 on a Super Alnico design as apparently that driver is a little more warmer and organic than the RS5.

That was very interesting comparison Seikosha. Were the coupling caps on both amps in the same league? Just curious since you said the Zen had the edge in midrange. Also what power tubes do you use with your Zen? The name says SE84 however Steve voiced and design the later models around the SV83/6P15P tube which is what I've always used.

Although my Super Zen Select is still breaking in the UFO transformers and probably the Jupiter Copper caps as well, I've quickly came to the same conclusion as you that the Zen sounds best on the Omegas with the 8 ohm tap. Is that still the tap that you're using with your Omegas? I know you said your two amps are very close but if you can only afford 1 amp to pair with your Omega speaker, which would be your choice and why?

Although detail and extension are important, I'm a midrange guy and for a single driver speaker that's what its all about. The only reason I brought this topic up was because I thought maybe being pseudo ( wired) SET, that no matter what my Zen amp is in a lower tier soundwise to a DHT SET.

I've spent a lot of time and money in upgrading my Super Zen Select and I wanted to make sure that it was well spent. Thank you for all the responses and feedback, this really reaffirmed my belief that the circuitry and execution of the amp is more important than the tube being used.

 

[DaveC113]

Just curious......what DIY EL34 SET amp are you referring to?

Thanks!

It's an Aikido preamp running 6SN7s which makes for 20 dB gain, it's output feeds directly (well, through Jupiter copper caps) to the power tubes in my driverless SET amp, which are EL34s wired in triode mode and then to James OPTs. The amp uses super low-ESR Clarity TC power supply caps exclusively, the preamp in the last filter stage. It uses high end parts throughout, Furutech binding posts and IEC inlets, pure copper RCA jacks, etc. There's probably $2k in parts invested.

There's Aikido schematics and tons of info in Broski's Tubecad blog. My preamp is a stand-alone unit with it's own power supply although it could easily be used as the driver section for a SET amp in the same chassis, in place of a more traditional driver section. The difference vs a single triode driver section, even CCS loaded, is massive as the Aikido circuit is more linear and produces far less distortion, which makes it sound more like a solid state amp, but the positive qualities of tubes still come through, like full body and tone, soundstaging, etc... Compared to most other SET amps it's clearer, faster, more detailed and more accurate. I have a small AB amp here that sounds more "tubey" and laid-back vs my SET amp.

[ozoid]

kevtn8—
Just curious as to which position you've put the output tap switches on your UFO. Mine are set toward the rear of the amp but I can't say I've noticed much of a difference. Steve declines to answer which is which.

[seikosha]

Hi kevtn8,

Parts quality is all very good in the custom amp.  If anything, I'd bet the transformers are better.  Don't get me wrong, the 2A3 sounds VERY good.  For example, for anyone who likes to listen to their Zen with the Bias on the hot setting, I'd bet they'd prefer the 2A3 for sure.  It's just a matter of personal preference, and if I was stuck with the 2A3, I wouldn't be upset at all.  In fact, I wish I preferred the 2A3 amp because the bass and extra power really is nice.

If I had to pick one, I'd stick to the Zen, but I'm keeping the 2A3 because eventually I'll probably end up with some Alnico's and I'd love to hear this amp with those drivers.

I use the stock tubes, including the SV83's.  I've tried EL84's but prefer the SV's and yes, I'm using the 8ohm tap.

[sruffle]

kevtn8—
Just curious as to which position you've put the output tap switches on your UFO. Mine are set toward the rear of the amp but I can't say I've noticed much of a difference. Steve declines to answer which is which.

Newbie question for me.  I have about 6 hours on my new SuperZen amp but also cannot figure out which is the 4 ohm and which is the 8 ohm tap.  I plan to try both but would like to know which is which.

[kevtn8]

For all Decware amps with the UFO transformers:

8 ohm tap is the switch facing towards the rear

4 ohm tap is towards the front

[kevtn8]

Hi kevtn8,

Parts quality is all very good in the custom amp.  If anything, I'd bet the transformers are better.  Don't get me wrong, the 2A3 sounds VERY good.  For example, for anyone who likes to listen to their Zen with the Bias on the hot setting, I'd bet they'd prefer the 2A3 for sure.  It's just a matter of personal preference, and if I was stuck with the 2A3, I wouldn't be upset at all.  In fact, I wish I preferred the 2A3 amp because the bass and extra power really is nice.

If I had to pick one, I'd stick to the Zen, but I'm keeping the 2A3 because eventually I'll probably end up with some Alnico's and I'd love to hear this amp with those drivers.

I use the stock tubes, including the SV83's.  I've tried EL84's but prefer the SV's and yes, I'm using the 8ohm tap.

All this talk about transformers and frequency extensions is kind of funny because before I upgraded to the Jupiter Copper caps and UFO transformers in my Zen Select, the tonal balance I had with my 3XRS was as perfect as I've ever heard.

I'm not sure if its the burn-in process for the new caps and transformers but lately, the treble has been a bit hot/edgy on certain songs and passages. Don't get me wrong, I don't regret these upgrades at all and believe that every single part of the frequency spectrum has improved. I just felt that the RS5 driver didn't need anymore emphasis on the highs/treble and therefore what I'm hearing is due to the increased resolution/detail that these new caps and transformers have brought to my system.

Due to this and also for the simple fact that I've always been curious of the sound of a good single driver Alnico speaker, I finally called Louis and sealed the deal. My hope is that the smoothness and warmth of the Alnico driver will compliment the Jupiter Copper cap and UFO transformer upgrades and give me the tonal balance that I previously had before with the Super3XRS.

[Bill Baker]

I think you'll find that once those copper caps settle in, the tone will even out and the aggressiveness in the upper end will go away.

When it come to 2A3 vs other lower power pentodes, I'll take the pentodes. One of my favorite amps right now is a my EL84 Parallel Pentode amp (about 10 watts) or single EL84 Pentode at about 5 watts (just pulling one of the EL84s out of the parallel pentode amp). I guess what im.trying to say is that I prefer EL84 tubes over a 2A3. The EL84 has more control.

Now a 300B is a different story. While the 300B and EL84 offer very different presentations, I can't 3asily decide between the two. I really like what I hear with a 300B tube buffer in from of the Pentode EL84.

It all depends on what I'm in the mod for. That's the luxury one gets from designing and building amps or having several different components on hand, you get to listen to whatever you're in the mood for! I'm sure most AC member have more than one amp and some probably have a closet full so you know what I mean. 

[ozoid]

Newbie question for me.  I have about 6 hours on my new SuperZen amp but also cannot figure out which is the 4 ohm and which is the 8 ohm tap.  I plan to try both but would like to know which is which.

I'd like to know too, but Steve's been coy about it. I can't hear a difference on my Alnico monitors. I'm thinking of forming a focus group of weinmaraners and see if they can tell. I did have an opportunity to A-B between the SE84UFO and a Select with the older transformer. That was a striking difference.

[pstrisik]

..........

Due to this and also for the simple fact that I've always been curious of the sound of a good single driver Alnico speaker, I finally called Louis and sealed the deal. My hope is that the smoothness and warmth of the Alnico driver will compliment the Jupiter Copper cap and UFO transformer upgrades and give me the tonal balance that I previously had before with the Super3XRS.

I think that is a safe bet!  Though you will likely get some easing with some hours on the new caps and transformers. 

The alnicos are an overall more natural sounding presence than the ferrites (IMO, having had both).  The ferrites have more on the high end for resolution.  I think that is the biggest defining difference.  There are lots of people that like that top end and would think the alnicos soft and lots of people that would think the ferrites to be too bright.  I think most of us that are working at the level of single drivers and low watt tubes have learned which way we lean by now.  Another comparison is the US speaker trends in the 1960's.  The difference between the "New England" sound - acoustic suspension models such as AR3a, AR2ax and the "West Coast" sound - like those vintage JBL's. 

Then, after all that, there is the personality of the various pieces upstream that help with all the shades in between!  Not to mention tube rolling.  It's nice to have it feel like an art:  Feeling, sensing, changing, balancing........   


          ..........Peter

[Canada Rob]

Good post Peter,

East Coast/New England sound vs West Coast sound, oh the memories!  I was in the audio industry when those were the bywords for what type of speaker "sound" one preferred.  You can add Infinity and EPI to the East Coast sound list.  If I were to place Omega in one of the camps, it would be firmly East Coast, even though Omegas are a ported speaker, they have that lovely controlled bass the acoustic suspension speakers were famous for, not to mention the superior wide open midrange and imaging.  The "Bass Reflex" JBLs, later Altec Lansing models, and Cerwin Vega were all clearly "West Coast" sound and were often but not always more efficient, and probably more popular out here in the west.

Your description of the Alnico sound is bang on.  They don't go as high in the top end as a 3 or 7, but yet, due to their flatter frequency response are able to extract more from a recording than the 3 or 7.  They also can handle complex music and dynamic swings the best of all the Omegas I've heard.

[pstrisik]

Good post Peter,

East Coast/New England sound vs West Coast sound, oh the memories!  I was in the audio industry when those were the bywords for what type of speaker "sound" one preferred.  You can add Infinity and EPI to the East Coast sound list.  If I were to place Omega in one of the camps, it would be firmly East Coast, even though Omegas are a ported speaker, they have that lovely controlled bass the acoustic suspension speakers were famous for, not to mention the superior wide open midrange and imaging.  The "Bass Reflex" JBLs, later Altec Lansing models, and Cerwin Vega were all clearly "West Coast" sound and were often but not always more efficient, and probably more popular out here in the west.

Your description of the Alnico sound is bang on.  They don't go as high in the top end as a 3 or 7, but yet, due to their flatter frequency response are able to extract more from a recording than the 3 or 7.  They also can handle complex music and dynamic swings the best of all the Omegas I've heard.

Thanks Rob.  I am still impressed when I hear evidence of that dynamic range capability in the Alnico Monitors.  Even with things like jazz vocals, there are times when I swear I can tell when the singer moves closer to the mike, thwacks of the upright bass, emphasized strikes on the piano - they are all like I've never heard before.

         ........Peter