SET amp owners thread

Can you elaborate on this more? Just trying to understand what advantage is getting diminished with higher power.

SETs are best used where with the right speakers you will have more nuance, agility, purer tone, flow, compared to a non-SET, without giving up energy and bass. This is best done when the speakers require very less drive, less grip, less power. Optimal speakers for this are extremely few in number - full rangers without crossover or simple two ways with minimal crossovers and woofers that can be easily driven. The moment you require more drive, power, grunt, grip, and you use low powered SETs, you will get restrictions in dynamic range, and bloated, slow sound. At this point push pull valves and later high quality SS amps start sounding better.

Ok, above is general theory, what does it mean in practice? If you have a speaker, and the chance to rotate amps, you will find certain speakers sound better as you move from high powered to low powered amps. Certain speakers sound better as you go the opposite, e.g. in the same room, with the Airtight 300b 10w amp and the 34 watt Airtight EL 34, the 300b sounded better on the Devore Orangutans, while the EL34 sounded better on the Cessaro Wagner (the Wagner was sounding restricted with the 300b, the Devore had more nuance, flow, ease with the 300b without giving up anything on dynamic range or bass). And yes, if anyone wants to know, I preferred the Devore even with the EL34 to the Wagner, but that is beside the context of this post.

In another room, the Devore sounded better with NAF 2a3, compared to Silvercore 833c (20w) or a 300b 20 watt amp or a jadis 100w integrated. But the NAF 2a3 had very restricted dynamic range with the Lansche in the same room and that required more power, ideally the Jadis. Now the Silvercore seems less nuanced compared to NAF 2a3 on the Orangutans, but comparing on vintage Tannoys, it is much more nuanced than KR audio integrated, and we preferred the SIlvercore even though there the KR had better drive and bass - the silvercore had enough to have a better balance with the added nuance.

Just to clarify, when I say nuance, I hear it in more inflections, and more notes within the same period, be it violin, or piano, or cello, or vocals. More intranote detail, rather than being glossed over.

Apart from Airtight, we have also done same manufacturer compares with Thomas Mayer's 46 vs 211 on Pnoe, and also compared NAT Magma on it.

The small tubes are not only 300b like you mentioned in your other post. 45, 46, 2a3, 4p1L, 604, AD1, PX4, PX25. there are many, too many to hear, but if you try two and your speaker runs out of steam you will know. There are extremely few speakers in this category of tubes. You will have to build your own with vintage woofers in a simple 2 to 3 way, or get a commercial full ranger like Pnoe or build one with AER or Lowther based on your budget. Or you will have to biamp the woofer with a more powerful amp.

Now, as you start crossing 10 watts requirement (e.g. Devore orangutans), you will find that these NAF 2a3 types, which are not single ended but PSETs or push pulls like Cubes EL84, start sounding very good. They are bringing in more drive and still having sufficient nuance. It will then be a toss up between them, and a 211, or GM70 to know which you prefer and based on manufacturer. You will immediately lose nuance but gain drive and power compared to single ended 45 or 46. Does the transformer matter? Of course. But I don't know anyone who puts a 211 transformer on a 45 amp. That is also why the lower power SETs are quite low cost - they just require much less in material.

There could be Lamm at 30 watts, Kronzilla at 50, special ones like Allnic which do powerful versions with 300bs which go up to 50 watts. If you need more than this you are really into territory with one or two SETs like NAT and the rest push pulls like CAT, Audio Research, VAC, etc. There are some exceptions, mostly one offs, like the KR VA 200, or Eimac based SETs like the Trafomatic Elysium which cross 100 watts. If your speaker has impedance dropping and requiring more drive and grip you are then requiring quality solid state amps (which I prefer to push pulls like AR or VTL or to these powerful SETs like NAT at that stage, i.e. on speakers like Apogee, Martin Logans, or any of the regular cones like Wilson, Magico, etc)
 
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It's flirting at the edge of usability with a 300b SET, and in another thread, it was stated that at least some development of the speaker was done with 300b SET.

Some flea powered snobs don't even credit 300b SET with being so called 'true' flea power, reserving that distinction for 45, 2a3, 50 etc. It was funny, I don't have the link, but one ancient SET crumble on audio asylum said he just threw out crates of 300b tubes that had gathered in theaters in the day because he said they were all junk, even the vaunted Western Electric 300b. That really made me laugh. He wouldn't listen to anything above 2a3 in power. There are even some low power snobs who listen to tubes in the half to three quarter watt range with highly efficient speakers.

I do think it is an education to hear a full range setup driven by a nice 45 amp, because it is unique and really scrambles the brain cells about what amplification is and should accomplish. When you hear what a well done 45 can do, a lot of amp mythology that you hear from many mavens about power etc. seems to evaporate and you wonder why other amps can't do what the humble 45 does.
Just don’t let Ked know you are driving your BG planar with a 45 amp...or god forbid a SET with more than 10 watts :eek:...both are cardinal sins in his amp universe. ;)
 
SETs are best used where with the right speakers you will have more nuance, agility, purer tone, flow, compared to a non-SET, without giving up energy and bass. This is best done when the speakers require very less drive, less grip, less power.
@bonzo75 Thanks for taking the time to provide the detailed note!
 
Just don’t let Ked know you are driving your BG planar with a 45 amp...or god forbid a SET with more than 10 watts :eek:...both are cardinal sins in his amp universe. ;)
The BG planar sounds wonderful with the 45 @ 300hz crossover. I have tried mightily to find a clipping or deficiency, even with very loud output, but I can't. The strange thing about the flea powers is they seem to either work completely or they fall apart completely without a lot of middle ground.

Some audiophiles who think they have plumbed every detail and nuance in their favorite signals would be surprised to hear the reveal through a good 45/efficient speaker combo of things they never thought were there.

Lately I have been using a VFET SissySit knock off from the Nelson Pass DIY community with a 6b4g DHT driver stage on the BG ribbon. It has some characteristics of 45 with much higher power but still does not quite get there.
 
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yes done all this for 2 years now thanks - I was just interested in where you landed with your choice of point and your specific drivers
yes, and it's a continous work because we are learning with our experience.... still in progress because I will see how it works as 3-way (currently I use the Mid & High on the same amplifier - high with -6dB as well), other point is a line-level with constant impedance and a true active-xo.
 
My xo-frequncies makes no sence for your system.... important is to know how it works, or better how to find the correct xo-frequency.
You have to measure your drivers / horns without a xo by using pink noise! Then look at the curves (slope etc.), store the curve (mid-high for example) as overlay and then measure the bass. Now you can use a xo point what you think is best. Build the xo and listen, listen for a month or so and notice the plus / minus points, correct the xo etc.

I'd recomment to use a DSP-xo for this because you have a large free of degree points (slopes, xo-frequency...)

Exactly what I am about to do. I have a mini dsp and 2 pair of monoblocks. In truth, my second set of amps have been out for repair and upgrade for 5 or 6 weeks. They are ready to send home but I'm away for a few weeks so I delayed shipment.

Once I have the rebuilt Black Shadows I will run them a couple months. They are totally rebuilt and need to break in. The only issue I have is I have 1 set of Inakustik Ref 2400 speaker cables. The second set I have is Graditech Lumi 1 that are not near the awg as the Inakustik and therefore don't have the depth and rich tone of the heavier cable.

I'm not sure what to do about cabling as that will throw off the values I fall on with the mini dsp. Especially the gain per channel.
 
I buildt a SPUD with a crazy overdone chokeinput psu and a single 6c45s that delivered 0,75 watt ...it was the best amp I´ve ever tried for pure harmonics,transparancy and speed and drove my AG Trio to crazy levels, except when junior made me play som dubstep....then it fell flat on it´s face in the lower register
 
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Exactly what I am about to do. I have a mini dsp and 2 pair of monoblocks. In truth, my second set of amps have been out for repair and upgrade for 5 or 6 weeks. They are ready to send home but I'm away for a few weeks so I delayed shipment.
Once I have the rebuilt Black Shadows I will run them a couple months. They are totally rebuilt and need to break in. The only issue I have is I have 1 set of Inakustik Ref 2400 speaker cables. The second set I have is Graditech Lumi 1 that are not near the awg as the Inakustik and therefore don't have the depth and rich tone of the heavier cable.
I'm not sure what to do about cabling as that will throw off the values I fall on with the mini dsp. Especially the gain per channel.

Thx for your reply, I have no experience with your cables you mention so it's not easy to give a recommendation. But I think the best is to try it out and listen (take some time for this)... and maybe you don't like both cables. Important is first the set-up of your XO and then look to the cables as point above the "i" ... Good luck!
 
Gentlemen,
Out of curiosity, which amps would you think would really work nicely with Alsyvox? 94 efficiency and no dips below 4 ohms seems like a dream come true, but I wonder if the really low powered stuff would be able to drive it
I would love to hear the AlsyVoxes driven by KR Audio Kronzilla amps :cool:
 
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Nope, can’t work...;)
I would bet quite a sizable sum that it would sound heavenly :p
I guess the AC Concero 65 would also sound magical :cool:
 
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Indeed...there are some, without experience, who tell us otherwise though...

You should be less obsessed with and try to get one system right for yourself since You always quote them as reference. You have been unable to sleep on this for three days move on now
 
You should be less obsessed with and try to get one system right for yourself since You always quote them as reference. You have been unable to sleep on this for three days move on now

My systems sound just fine, thanks for your concern... One system is fixed and the other is for experimentation...I made this clear a long time ago, what didn't you understand? Do you now want to tell me my own motives for what I do?

You should get a system (right or wrong) and stop obsessing period (nearly 15K posts and still no system)...
 
My systems sound just fine, thanks for your concern... One system is fixed and the other is for experimentation...I made this clear a long time ago, what didn't you understand? Do you now want to tell me my own motives for what I do?

You should get a system (right or wrong) and stop obsessing period (nearly 15K posts and still no system)...

I am worried I might end up like you and won't be able to see right from wrong. It is hilarious you think your fixed system is a reference model
 
I am worried I might end up like you and won't be able to see right from wrong. It is hilarious you think your fixed system is a reference model

That ship sailed long ago...you have no idea right from wrong...

What's hilarious is that you think I think my system is some kind of absolute reference...I have said many times my reference is live, unamplified music.

You are the one now holding up the Altec style FLH horn system as being "right" and no one else's system is worth a damn anymore...

You want to tell Ex Libris that his new Odeons are crap? We have gone round and round about that brand (I like them very much you for some unclear reason do not) I know you think that...why you would provide him amp suggestions for a pair of speakers you don't like is beyond me. We have at least three great sounding systems here in Switzerland/Liechtenstein based on those speakers...many are impressed and your opinion has not more weight than theirs (perhaps less as you have no system to even have some idea what your abilities as a system builder are...last you had I believe was a small pair of Verity and a VAC 30/30 (a mediocre system that one of my customers dumped a long time ago)).
 
Seriously, you need to move on. I have zero interest in your posts. You don't even quote me correctly
 
Seriously, you need to move on. I have zero interest in your posts. You don't even quote me correctly

Did I quote you at all? There are no quotes in my post. You have zero interest, yet you can't help responding...also on my own speaker design thread, which there was no reason for you to necessarily post (you are not building a system and most responders have either built or were actively building a speaker system). I finally had to tell you stop posting on it because you were so obnoxious.

I was trying to support Ex Libris in amps...you started in again on what you think of my system and design (neither of which you have heard in person). I cannot let your personal attacks just go and so you have my strong response and pushback. When you learn to post with some respect you will receive some in kind.
 
I didn't start here, you started attacking me. Go read the start of this conversation. When I made an observation in post 1367 that disagreed with yours, you got personal. Even on your thread I simply made a suggestion where you started attacking me. I do understand your insecurity
 

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