SET amp owners thread

I have heard 3 mega horns with Accuphase filter now, their tone just didn't work, totally undid the magic. They had very good top to down extension and rest of the stuff as they were complex multi-ways
 
I have heard 3 mega horns with Accuphase filter now, their tone just didn't work, totally undid the magic. They had very good top to down extension and rest of the stuff as they were complex multi-ways
That is why I sold mine. I would go tube now with an active analog xover
 
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I am quite happy with F25 which give very musical sound.

But I had never tried Pass XVR1.

Maybe I will not try Pass XVR1 in the future since I am rather disappointed with Pap C1
I'm not actually defending the XVR1, as I've never heard one, but by I've never seen a bad review and a quick look at the internals shows that they are very different designs. I just don't think you should dismiss it out of hand based on your experience with the PAP version.

It does seem like PAP really charge a premium for that little guy, I was shocked at the price total given what they charge over at the DIYAUDIO store for pretty similar looking crossover kits also designed by Nelson (a couple hundred for the full build).
 
In a 2-way wold, yes ! If you are thinking 3 or 4-way the F-25 is the thing to have. But you will need to know what crossover points you are aiming for…
One can do 4- channels, but then you’d need a second control unit that can be powered by the same PSU
 
One can do 4- channels, but then you’d need a second control unit that can be powered by the same PSU
Yes I know, have done that back in 2004. But the price…! and a second unit will only bring you to 3-way.. for a full 4-way system you’ll need 3 units an maybe one more power-unit. Makes you car look inexpensive.
 
Yes I know, have done that back in 2004. But the price…! and a second unit will only bring you to 3-way.. for a full 4-way system you’ll need 3 units an maybe one more power-unit. Makes you car look inexpensive.

You guys should try Werner Jargusch's passive crossover (doesn't cost much and with one iteration should sound musical) or fly over Misho from Bulgaria to do a passive for the 817 since he has an excellent sounding one
 
I'm not actually defending the XVR1, as I've never heard one, but by I've never seen a bad review and a quick look at the internals shows that they are very different designs. I just don't think you should dismiss it out of hand based on your experience with the PAP version.

It does seem like PAP really charge a premium for that little guy, I was shocked at the price total given what they charge over at the DIYAUDIO store for pretty similar looking crossover kits also designed by Nelson (a couple hundred for the full build).
I believe you are talking about this one. Compared to all the other solutions mentioned here it's super cheap, but still... Designed by Papa Nelson. Worth giving a shot if you can assemble it/have someone do it. It is a super simple solution, no feedback. It would go with SET amplifiers like a dream!
 
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I've been asked a lot about electronic crossovers by customers over the last 45 years or so.

IMO/IME the more transparent your system is, the more you can hear what they do. I regard them as detail and bandwidth filters. For this reason I prefer speakers that allow me to run the amplifier full range on the loudspeaker, as so far that has proved out to be the most transparent. I know a lot of 'full range' driver people hate the idea of a crossover in front of their (usually really expensive) 'full range' driver, but the simple fact of life is that any excursion of the driver caused by bass notes for which the driver isn't coupled into the room (and even if it is, but to a far lessor extent) causes very audible Doppler Effect distortion, which causes the driver to sound harsher and less detailed. That's the opposite of what you want out of such a high quality driver!

If you somehow limit the excursion by placing the 'full range' driver in a box that acoustically limits its bandwidth, you still have to deal with the fact that the out-of-band bass notes are heating up the voice coil, causing thermal compression.

So you simply have to have a crossover, since all 'full range' drivers are really just wide band midrange drivers, part of a 3-way system if we're all being honest. The best place to put that is between the amp and drivers, no doubt why 99% of all loudspeakers made use this technique.

We ran a high end crossover (balanced, all-tube) at a show one time (RMAF, about 10 years ago) with the intention of bi-amplifying the Classic Audio Loudspeakers T-1s that we were using in a ballroom-sized room on the first floor. I have recordings that I use for test like many audiophiles; some of them are recordings I made and released on LP so I know how they are supposed to sound. The simple fact was the crossover was losing detail; when we got it out of the system and ran the speakers full range the detail and bass impact returned. I know this is anecdotal but FWIW I've seen this played out a lot. No doubt you can probably get an electronic crossover to work fairly well, but the question is how well would it work if the speaker could simply be driven full range?
 
I believe you are talking about this one. Compared to all the other solutions mentioned here it's super cheap, but still... Designed by Papa Nelson. Worth giving a shot if you can assemble it/have someone do it. It is a super simple solution, no feedback. It would go with SET amplifiers like a dream!
Indeed. There's both that one and then the newer 6-24 option: https://diyaudiostore.com/collections/crossovers/products/diy-biamp-6-24-crossover

"The DIY BIAMP 6-24 kit is a stereo analog active biamp crossover circuit designed for high flexibility. Featuring 12 discrete Jfet buffer circuits operated without negative feedback, it offers 16 continuously adjustable filter elements in two low-pass and two high-pass filters with slopes of 6, 12, 18, or 24 dB per octave and various “Q” characteristics. It has flexibility not generally offered by crossover products have “textbook” characteristics, allowing more detailed tailoring of filters around the actual character of different loudspeaker drivers."
 
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@Atmasphere in my opinion losing detail in crossovers is usually due to the reactance of the crossover network. It's way harder to drive than most people know. That includes both passive speakers and active crossovers. Driving them requires both current and voltage far exceeding what you would expect from just simple calculations. With tubes, we get lots of voltage headroom and more sensitive speakers. With semiconductors more output current and low sensitivity, low impedance speakers.

Indeed. There's both that one and then the newer 6-24 option: https://diyaudiostore.com/collections/crossovers/products/diy-biamp-6-24-crossover

"The DIY BIAMP 6-24 kit is a stereo analog active biamp crossover circuit designed for high flexibility. Featuring 12 discrete Jfet buffer circuits operated without negative feedback, it offers 16 continuously adjustable filter elements in two low-pass and two high-pass filters with slopes of 6, 12, 18, or 24 dB per octave and various “Q” characteristics. It has flexibility not generally offered by crossover products have “textbook” characteristics, allowing more detailed tailoring of filters around the actual character of different loudspeaker drivers."
Oh, that's cool too. I've seen those simple J-FET buffers in so many audio pieces of equipment...
 
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I can run my system as single amp/single panel without any crossover, or I can add a low frequency active cutoff and operate it with a subwoofer, or operate it full out as a four way active with the extra ribbon/tweeter components and the Accuphase F25.

Single panel crossover-less/single amp sounds great, and once in a while I will listen to that as balance reference and because of sheer simplicity without turning a bunch of stuff on.

Is it better than the four way active? Not a chance in hell. The four way active is much better, including detail retrieval and overall impact/ imaging/etc. It is markedly superior to the crossover-less experience.

The problem with active crossovers is they are complicated with lots of permutations, and you have to be very careful with the phasing of the crossover and the speaker elements for a particular room, especially for the bands adjacent to the midrange.

I wouldn’t go back to passive. I won’t comment on passive crossovers, because hackles will be raised and retaliatory rages will be inspired to no avail.

I do have the advantage that ribbons are easier to integrate with active crossover than horns, which have all of those complex electrical response patterns. The horns will have special requirements. I do know that the F25 had very special crossover cards for particular JVC horns, but I never really hear about them any more.

I had tubed crossovers, but I like the F25 better. You stack those racks of small signal tubes, I don't think there is anyway to avoid compression effects, even if you get a bit of the tube ethos.
 
First, my philosophy is to make things no more complicated than they need to be and I have an emphasis on creating a sense of immersion and realistic sounding timbre on acoustic instruments and vocals. That lead me to a 3-way horn speaker using a very fast and light wideband midrange driver that covers 400-12000 Hz in a LeCleach horn.

This has a lot of advantages, 400 Hz is low enough either a passive or active/DSP crossover can be used on the woofer with little difference. For the mid, 400 and 12 kHz are out of the most sensitive ranges of our hearing and 1st and 2nd order only use a single component in series with the driver. A really good cap or coil doesn't ruin everything, lol. You can also use no crossover at all on the midrange if SPL is low, a 1st or 2nd order works too, and which is better depends mainly on the recording as well as the volume. Girl w/guitar at low SPLs? No xo or 1st order, both are good ime.... Higher complexity at higher SPLs? 2nd order, no contest, and on the low end I also go parabolic 2nd order.

The end result is there is no best answer, I think different approaches are valid implementation is the key factor in how well it works. Once I do start building speakers for sale the passive crossover will be external and quite adjustable so anything the owner likes can be implemented. My approach is only one way to do things though, there's good speakers of all types these days and a very large, expensive and more complex conventional 4-way speaker using drivers that require a steep slope xo often has advantages on complex music vs simpler speakers that use wider bandwidth drivers and simpler xo's.
 
I've been asked a lot about electronic crossovers by customers over the last 45 years or so.

IMO/IME the more transparent your system is, the more you can hear what they do. I regard them as detail and bandwidth filters. For this reason I prefer speakers that allow me to run the amplifier full range on the loudspeaker, as so far that has proved out to be the most transparent. I know a lot of 'full range' driver people hate the idea of a crossover in front of their (usually really expensive) 'full range' driver, but the simple fact of life is that any excursion of the driver caused by bass notes for which the driver isn't coupled into the room (and even if it is, but to a far lessor extent) causes very audible Doppler Effect distortion, which causes the driver to sound harsher and less detailed. That's the opposite of what you want out of such a high quality driver!

If you somehow limit the excursion by placing the 'full range' driver in a box that acoustically limits its bandwidth, you still have to deal with the fact that the out-of-band bass notes are heating up the voice coil, causing thermal compression.

So you simply have to have a crossover, since all 'full range' drivers are really just wide band midrange drivers, part of a 3-way system if we're all being honest. The best place to put that is between the amp and drivers, no doubt why 99% of all loudspeakers made use this technique.

We ran a high end crossover (balanced, all-tube) at a show one time (RMAF, about 10 years ago) with the intention of bi-amplifying the Classic Audio Loudspeakers T-1s that we were using in a ballroom-sized room on the first floor. I have recordings that I use for test like many audiophiles; some of them are recordings I made and released on LP so I know how they are supposed to sound. The simple fact was the crossover was losing detail; when we got it out of the system and ran the speakers full range the detail and bass impact returned. I know this is anecdotal but FWIW I've seen this played out a lot. No doubt you can probably get an electronic crossover to work fairly well, but the question is how well would it work if the speaker could simply be driven full range?
This is a very confusing comment. It sounds like you want a full range driver, no crossover, active or between the amp and driver. If you try to go without a crossover, you have distortions, so your back to a crossover. And around and around we go.

I removed all the crossover cabling from my PAP and drove the Voxativ direct from the amp. The most amazing violin I ever heard. As soon as the piano and singer started, it all went kaplooie. So I have a crossover. I have not found a way to get rid of it.
 
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This is a very confusing comment. It sounds like you want a full range driver, no crossover, active or between the amp and driver. If you try to go without a crossover, you have distortions, so your back to a crossover. And around and around we go.

I removed all the crossover cabling from my PAP and drove the Voxativ direct from the amp. The most amazing violin I ever heard. As soon as the piano and singer started, it all went kaplooie. So I have a crossover. I have not found a way to get rid of it.
I will eventually try a tube xover from Marchand as an analog active. I had an Accuphase F25 in the past and while good, it was not totally to my liking in what it did to the tonality of the system.

My current setup is for digital only but I use a digital xover (mini-DSP nano-digi) with my own DACs, which sound much better than those typically found in speaker management systems (and better than the F25 for digital). The amps are fed from the DACs (Ayon Spark integrated on the mid/bass driver and 300B monoblocks regulated passively on the mid/high horn) and the amps drive the speaker drivers directly...sounds very good and alive but doesn't work with analog unless I digitize first...not the best option.
 
My speakers have a jumper you can remove and then they are biamped. I tried to insert 4 amps but I got a ground loop. I think between the 4 amps at the preamp. Not sure. And it was the Dartzeel that was unhappy. I want to try again.

In my case it would only be separating the woofers from mid/high freq drivers. I thought of a Marchand myself. Good for the $. Never saw a tube unit from him.
 
I removed all the crossover cabling from my PAP and drove the Voxativ direct from the amp. The most amazing violin I ever heard. As soon as the piano and singer started, it all went kaplooie. So I have a crossover. I have not found a way to get rid of it.

That's exactly what the AER pnoe did very well, played the whole range without a crossover but too expensive. Maybe feastrex also can
 
This is a very confusing comment. It sounds like you want a full range driver, no crossover, active or between the amp and driver. If you try to go without a crossover, you have distortions, so your back to a crossover. And around and around we go.

I removed all the crossover cabling from my PAP and drove the Voxativ direct from the amp. The most amazing violin I ever heard. As soon as the piano and singer started, it all went kaplooie. So I have a crossover. I have not found a way to get rid of it.
The reason it sounds that way is I was trying to help a local customer out with his foray into 'full range' drivers. He was not good on taking advice from schooled engineers and was religious about No Crossover. Over a period of three years I kept telling him he was going to need one. Had I not known him for 40 years I likely wouldn't have put in the time. My experience is the same as yours.

'Full range' drivers do not exist.

Anyone that tries to run them sans crossover will find that only certain types of lightweight music without bass can be played properly. For that they can do quite well although the highs will be beamy (you need a tweeter too).

For that reason I've come to the conclusion that the Holy Grail of doing everything with one driver and no crossover is a fool's errand- a Sisyphean task. It simply won't work, physics and all... people that don't like hearing this will do well to pay attention anyway. Honestly I see no reason why a skilled engineer would pursue the design of a 'full range' driver when its obvious it simply isn't going to work (I don't see the point in going over probably about 6"). But I can see plenty of reason to use such a driver in a speaker that employs a crossover, such as some of the Spatial Audio or PureAudio products.
 
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That's exactly what the AER pnoe did very well, played the whole range without a crossover but too expensive. Maybe feastrex also can


The truth is it's a physical impossibility for a BLH like the pnoe, or any enclosure for that matter, to eliminate all of the intermodulation distortion that will occur when playing full-range complex music at higher SPLs. While I have no doubt the AER/pnoe may be the world's best single driver speaker it's absolutely not possible for it to compete with a competent multi-way speaker with crossovers in this regard.
 
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The reason it sounds that way is I was trying to help a local customer out with his foray into 'full range' drivers. He was not good on taking advice from schooled engineers and was religious about No Crossover. Over a period of three years I kept telling him he was going to need one. Had I not known him for 40 years I likely wouldn't have put in the time. My experience is the same as yours.

'Full range' drivers do not exist.

Anyone that tries to run them sans crossover will find that only certain types of lightweight music without bass can be played properly. For that they can do quite well although the highs will be beamy (you need a tweeter too).

For that reason I've come to the conclusion that the Holy Grail of doing everything with one driver and no crossover is a fool's errand- a Sisyphean task. It simply won't work, physics and all... people that don't like hearing this will do well to pay attention anyway. Honestly I see no reason why a skilled engineer would pursue the design of a 'full range' driver when its obvious it simply isn't going to work (I don't see the point in going over probably about 6"). But I can see plenty of reason to use such a driver in a speaker that employs a crossover, such as some of the Spatial Audio or PureAudio products.
Acoustat panels did full range very well...different tech but they were indeed full range (I got 20hz in my room with the big Acoustat Spectra 4400s). Other than a somewhat low sensitivity it is the best full range driver in existence I think...driving them directly with an OTL (their first iteration was just that kind of direct drive...same for Beveridge) is supposed to be one of the best sounds one can get...minus perhaps horn dyanmics.

As to cone full range, the Whizzer is, IMO a disaster excuse for a tweeter...no matter what Cube Audio tries to do. The best thing is to not have one, like Supravox or what Horning does to the Lowthers and then put a tweeter with it...which means a crossover. So far I am finding active works very well and seems to be more lively than most passive setups. Horning doesn't have a crossover on the Lowther they de-whizzed and without it rolls off more or less naturally. SUpravox is very well behaved this way and don't really need a crossover either, depending on the frequency you wnat to roll in the tweeter.

Reference 3A has been doing the crossoverless mid/bass for decades and they sound quite good (probably my top 3 box speaker), so the amp is connected directly to the driver.
 
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