What speakers are these? By LM line magnetic? The midbass below still doesn’t seem to be horn loaded thoughIn my case, however, I prefer really loud speakerswhether with a horn (LM Iconic) or without a horn (LaVoix).
What speakers are these? By LM line magnetic? The midbass below still doesn’t seem to be horn loaded thoughIn my case, however, I prefer really loud speakerswhether with a horn (LM Iconic) or without a horn (LaVoix).
Generally speaking, asking an SET to make bass is a bad idea if you want the most out of the amp in terms of sound quality. This is because the load line for the output tubes becomes non-linear as frequency goes down, if the output transformer has a cut core, which is present in most SETs (unless its a parafeed design).In this regard, the Phasemation MA 5000, which @dcc uses with the large Stenheim, could be interesting. 2 x 45 W from one pair of WE211 each. But is it enough for the Stenheim 5? I don't know.
I heard the Phasemation MA-5000 amplifiers in Tokyo.In this regard, the Phasemation MA 5000, which @dcc uses with the large Stenheim, could be interesting. 2 x 45 W from one pair of WE211 each. But is it enough for the Stenheim 5? I don't know.
Unfortunately, I've only heard Stenheim in Munich on Nagra and DartZeel – neither of which were good for me. But in a home or at a dealer's, with plenty of time to put together a system that has really grown, the result can be much better, I realise that.
In my case, however, I prefer really loud speakerswhether with a horn (LM Iconic) or without a horn (LaVoix).
Strange ,
I’m now assuming you have never heard a proper SET amp/Speaker setup Ralph , when done correctly its the bass which separates them apart from OTL’s and regular PP tubes..!
SET bass articulation Speed and jump makes it the business …!
This is nonsense, starting with the idea that you think I've not had exposure to SETs in the last 50 years...
SETs have the least low frequency bandwidth of any kind of amplifier. Its not logical or provable that they could actually play deeper and more articulate bass. In terms of speed, which is easily measured, they are also the slowest. 'Jump' simply arises from distortion caused by the user attempting to use the amp with a speaker that lacks the efficiency to really show off the amp. SETs make the most higher ordered harmonics of any kind of amplifier technology, and so at power levels above about 20% of full power those harmonics masquerade as 'jump'. But its really just distortion.
Its OK if you like that sort of thing.
The most successful SET setups I've seen, and the people most ardent about them that I know, have in common one thing: they prevent bass from entering the amplifier, to allow the amp to put its best foot forward.
So now I'm going to explain again why bass is such a big deal to SETs.
Inductance is required for any transformer to work. It is inductance that allows a couple hundred Ohms worth of wire to actually have an impedance of 3000 to 10,000 Ohms when in the output transformer. DHTs and pentodes usually require a load somewhere in that range. The inductance falls off at low frequencies, regardless of if the transformer is for PP or SET, until only the DC resistance of the wire is left. Because there is a gap in the core laminations of the output transformer of SET output transformers (there to prevent DC saturation), the low frequency inductance falls off much faster as frequency goes down. This causes the power tube to see a much lower impedance if driven at those frequencies. So with SETs this problem is profound and the bass frequencies in question are in the audio band. The bigger the amp, the more likely this problem exists well into the upper bass.
The reason we've seen a trend over the last 20 years to larger output transformers in SETs, such as a 35 Watt device meant for a single 300b that only makes 7 Watts, is to help get around this problem. If you know that the 35 Watt transformer is only going to see 7 Watts, you can make the gap in the core smaller, thus increasing low frequency inductance while still controlling DC saturation.
When I talk about technical things and the measurements surrounding them, its important to understand that this is engineering which makes the amps possible in the first place. They are not made from a magical conjuring. This low frequency problem is very real and every SET designer knows about it whether they care to admit or it not. Those that make SETs but really didn't design them might still be in the dark about this; there are a few of those in this industry... But talk to any designer of SET output transformers and you'll find out quite quickly how real this is.
When the tube of an SET is trying to drive a near short when playing a low bass drum, it simply has to make a lot of distortion since its non-linear at those frequencies. This is really easy to hear and really easy to measure and its hard on the tube. A sine wave put through an SET at full power at 20Hz doesn't look like a sine wave at the output; when distortion is so bad you can see it on a 'scope without having to use an analyzer, you know you have a problem.
Rather than attack me on this, you could try taking my advice (which isn't to dump the SET), which is simply to place a small capacitance upstream of the amp so as to limit bass entering it. I provided a formula to calculate the value of the cap on the thread about Ron's system. The result is similar to what happens to an ESL if you prevent bass from modulating its panel or what happens when you do the same with a 'full range' driver. In all cases you get cleaner sound which is easily heard as smoother with greater transparency. The downside is you have to come up with some kind of woofer or subwoofer system to make the bass.
That could be one way to do it. You might have some difficulty with the blend if two different kinds of amp technology are used, but if you get the gain right and the phase of the bass amp right it might go fairly well. Does your speaker allow you to bi-amplify?Ralph, are you suggesting that someone who has a two-way horn system like I do with a crossover at 500 Hz actually use an SET for the upper horn in a different amplifier for the lower horn with some kind of active or passive crossover?
David uses a pair of ML2 for his JBL subwoofers. I have a second pair and wonder what my speakers would be like if I used 2 amps per speaker. It would certainly get hot in the summer.
That could be one way to do it. You might have some difficulty with the blend if two different kinds of amp technology are used, but if you get the gain right and the phase of the bass amp right it might go fairly well. Does your speaker allow you to bi-amplify?
But I had in mind to cross over at a lower frequency- 200Hz or less. If you had a sub set to run up to 70 Hz you could cut off at that frequency. Since many subs have their own crossovers this would be fairly easy to set up- all you'd have to do is calculate the cap value needed at the input of the amp.
The schematic of your speaker suggests its really only built for one amp, but it is designed so with minor modification it could easily be run by two if you split up the speaker connections properly. The reason for the level control on the horn is to allow the user to adjust the speaker to the power response of the amplifier to the load (rather than anything to do with bi-amplifying), since back in the day when this speaker was designed, the Voltage rules that are used in loudspeaker design now had not yet been defined.Thanks, Ralph. I’ve got two pair of identical ML2 amplifiers. I do not want to mix amplifiers. I think my speakers do allow for biamping and they have an attenuation dial for the upper horn I think for the purpose of blending. I might try it this fall when the weather cools down.
That said, I didn’t like the Stenheim–DartZeel pairing in Munich, but I don’t think that setup represents the true Stenheim sound.
The best I ever heard from Wilson was the old X1 driven by KR Audio SET amps. This was actually pretty impressive.I think Some cone speakers like living voice r25, Stenheim, old big wilsons (alexandria), Kaiser are better with tube amplification.
I really liked our old X1s...after passing on the X2 Series 1 and 2, I found overall I preferred the XLF by a significant enough margin that we went for it after they were replaced by the new XVX. Big discount and with the trade-in of the original X1s at actually what we had paid for them 10 years prior...quite a nice overall trade.The best I ever heard from Wilson was the old X1 driven by KR Audio SET amps. This was actually pretty impressive.
I really liked our old X1s...after passing on the X2 Series 1 and 2, I found overall I preferred the XLF by a significant enough margin that we went for it after they were replaced by the new XVX. Big discount and with the trade-in of the original X1s at actually what we had paid for them 10 years prior...quite a nice overall trade.
In fact, I have PMd you for another piece of advice on that!
Yes, you've been quite consistent on that. The problem for me with the old X1 was despite its sense of freedom of expression, its cabinetry and other elements were not nearly as solid as its later generations and as a result, the signal never found its way all the out the other side without a lot of further work. There was a sense the signal could not travel straight thru the speaker...whereas for me, the XLF does that a lot better with greater solidity and resolve.All the XLFs, X2S2s, and the XVX I heard were quite poor compared to the old X1
Yes, you've been quite consistent on that. The problem for me with the old X1 was despite its sense of freedom of expression, its cabinetry and other elements were not nearly as solid as its later generations and as a result, the signal never found its way all the out the other side without a lot of further work. There was a sense the signal could not travel straight thru the speaker...whereas for me, the XLF does that a lot better with greater solidity and resolve.
I feel like the XLF does not have as much as the absolute freedom of dynamics that the X1 does, BUT that said, it does have a much more solid delivery overall, more resolved, more confident...and net, net in comparisons over months, I definitely preferred the XLF and felt that DW had created a better version of his original vision.
Yes, it describes what I feel when I heard the X1...it seems to very easily accept musical signal and transfer it out. The key is that while that freedom of expression is clear, and 'breathes easily'...I also found 'not all the signal' might have actually come out. Somehow, the physical/electrical/whatever pathway seemed 'shaky' in comparison with later generations of big Wilsons so what came thru breathed easily but it seemed a slightly truncated version of what went into the signal from the sources/ampsLloyd, this expression is fabulous:
“…its sense of freedom of expression…”
Yes, you've been quite consistent on that. The problem for me with the old X1 was despite its sense of freedom of expression, its cabinetry and other elements were not nearly as solid as its later generations and as a result, the signal never found its way all the out the other side without a lot of further work. There was a sense the signal could not travel straight thru the speaker...whereas for me, the XLF does that a lot better with greater solidity and resolve.
I feel like the XLF does not have as much as the absolute freedom of dynamics that the X1 does,
BUT that said, it does have a much more solid delivery overall, more resolved, more confident...and net, net in comparisons over months, I definitely preferred the XLF and felt that DW had created a better version of his original vision.
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