Field Coil Speakers @ 16 Ohms for OTL

Phantom-Audio

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Here is a pair of 2 Very different types of speakers

Classic Audio Loudspeakers 16-Ohms 100db using Beryllium Horn Drivers & Tube Field Coil Power Supplies

Line Magnetic Version of the Western Electric Horn Speakers also at 16-Ohms 105db also using Tube Field Coil Power Supplies.

Both are on the Atma-Sphere Nirvana OTL Amplifiers i switch back and forth at times.
 

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Addicted to hifi

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Here is a pair of 2 Very different types of speakers

Classic Audio Loudspeakers 16-Ohms 100db using Beryllium Horn Drivers & Tube Field Coil Power Supplies

Line Magnetic Version of the Western Electric Horn Speakers also at 16-Ohms 105db also using Tube Field Coil Power Supplies.

Both are on the Atma-Sphere Nirvana OTL Amplifiers i switch back and forth at times.
Very very nice.
 
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DetroitVinylRob

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Yes, it would be very interesting to know more about these two wonderful speakers.
 

dcathro

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Here is a pair of 2 Very different types of speakers

Classic Audio Loudspeakers 16-Ohms 100db using Beryllium Horn Drivers & Tube Field Coil Power Supplies

Line Magnetic Version of the Western Electric Horn Speakers also at 16-Ohms 105db also using Tube Field Coil Power Supplies.

Both are on the Atma-Sphere Nirvana OTL Amplifiers i switch back and forth at times.

They look magnificent!

Which are your favourites?
 

DetroitVinylRob

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Well, I will comment that our Classic Audio 16? FC T3.4’s that John Wolfe delivered last October are the first foray into magnet-less loudspeakers and we could not be happier. Not to go without mention, the hand rubbed rosewood cabinets are magnificent also. We run Atma-Sphere OTL amps in the new mix and have enjoyed the MA1’s for over a decade, but with these loudspeakers it is simply heavenly and revealing. Currently charging the FC’s with a pair of TK Precision regulated power supplies @18vDC and looking to understand possible options from there… Wondering what else PS wise is available? Not much of a DIY guy.
 
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audioquest4life

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Your sentiment is the same as mine regarding the Classic Audio loudspeakers. I have the T1.5s. They do reproduce beautiful music, that’s for sure. The FC concept is a game changer to me due to the naturalness of the music. I just can’t believe how voices sound in these speakers, or just about anything else as these speakers convey a lifelike quality to music. I am using the same power supplies and really find no reason to change them out. I am also not much of a DIY person, therefore, believe in keeping it simple whenever possible. I may be changing up amps to the new MC3500 that McIntosh just announced. The dynamic range is said to be better than the MC2301, if that’s even possible. Ironically, they will use a tube that is often used in OTL applications.
 

Phantom-Audio

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Having tried PP, SET and OTL Amps on the classic Audio Loudspeakers, I prefer the OTL formost over the others. However SET is not far behind. Even the MA-1 or M60 will power up these speakers with out issues and the transaprency will rival anything else available regardless of price.

Iv tried SS and Tubes Power Supplies on the Classic Audio Loudspeakers and by far the Tube Power supplies are a step above any SS Power supply iv been using in my previous years. If you have not tried the Tube Power supplies for the field coil section your really missing out on what the the Classic Audio Loudspeaker are capable off.
 
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Phantom-Audio

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They look magnificent!

Which are your favourites?
Classic Audio Loudspeakers but the Line Magnetic is not far behind. The presentation of both the speakers are diffrently potrayed in the room.

Line Magentic seem to have a romatic/Softer presentation, a warm sounding speaker but very musical that draws you in deep and makes you forget about the electronics.

The classic Audio loudspeaker is more truthful to the source, has similar quality to the Line Magnetic in terms of Musicality but is more revealing on the finer nusance.

I cant live with out both, iv been asked this questions a dozen times if i had to choose one which would it be, and yet i lean ever so slightly to the Classic Audio Loudspeakers.
 

audioquest4life

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Sep 23, 2020
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Having tried PP, SET and OTL Amps on the classic Audio Loudspeakers, I prefer the OTL formost over the others. However SET is not far behind. Even the MA-1 or M60 will power up these speakers with out issues and the transaprency will rival anything else available regardless of price.

Iv tried SS and Tubes Power Supplies on the Classic Audio Loudspeakers and by far the Tube Power supplies are a step above any SS Power supply iv been using in my previous years. If you have not tried the Tube Power supplies for the field coil section your really missing out on what the the Classic Audio Loudspeaker are capable off.
What Atma-sphere amps have you used with the T1.5s? Is 60 watts enough for a 30 x 18 x 8 sized room with T1.5s? If I were to try out any Atma-sphere amp with my T1.5s, I would be inclined to use them with either the Novacron or MA-1 due to their higher output in watts. Have you ever tried any Air Tight SET amps?

The T.15s are rated at 16 ohms, so power output should increase into 16ohms relative to the 8ohm output ratings.
 

thomask

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Classic Audio Loudspeakers but the Line Magnetic is not far behind. The presentation of both the speakers are diffrently potrayed in the room.

Line Magentic seem to have a romatic/Softer presentation, a warm sounding speaker but very musical that draws you in deep and makes you forget about the electronics.

The classic Audio loudspeaker is more truthful to the source, has similar quality to the Line Magnetic in terms of Musicality but is more revealing on the finer nusance.

I cant live with out both, iv been asked this questions a dozen times if i had to choose one which would it be, and yet i lean ever so slightly to the Classic Audio Loudspeakers.
Could you upload video to compare both speakeres?

thanks
 

ACHiPo

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What Atma-sphere amps have you used with the T1.5s? Is 60 watts enough for a 30 x 18 x 8 sized room with T1.5s? If I were to try out any Atma-sphere amp with my T1.5s, I would be inclined to use them with either the Novacron or MA-1 due to their higher output in watts. Have you ever tried any Air Tight SET amps?

The T.15s are rated at 16 ohms, so power output should increase into 16ohms relative to the 8ohm output ratings.
I auditioned a pair of T1.5s driven by Novacron monoblocks (~30-40 watts as I recall?) and there was plenty of dynamics in a room ~25' x 20' x 8'. The system did sax, trumpet, and drums better than anything I've heard. I ultimately decided not to pursue the T1.5s, but I can understand the attraction.
 

adrianywu

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I bought the 4" compression drivers and the 15" woofers from Classic Audio about 6 years ago to replace my JBL/Altec drivers. I was using the EV T350 tweeters at the time, but I have since changed to the Acapella ion tweeters. Love the sound. Only using the solid state regulated field coil power supply that John sent with the drivers. The tweeters are extremely fast and transparent, and I think only the field coil drivers are able to keep up with them. I am using an Accuphase F25 electronic crossover, and I am using two pairs of 300B differential PP amps for the tweeter and midrange, and a Parasound A23+ ss amp for the bass. The sound is very natural and dynamic, which can be attributed to the field coils, and having no passive crossover. I would love to play with the Line Magnetic replica drivers. I have a friend who collects Western Electric gear. A pair of WE755a in original cabinets had the most gorgeous mid-range.
 
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Phantom-Audio

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I bought the 4" compression drivers and the 15" woofers from Classic Audio about 6 years ago to replace my JBL/Altec drivers. I was using the EV T350 tweeters at the time, but I have since changed to the Acapella ion tweeters. Love the sound. Only using the solid state regulated field coil power supply that John sent with the drivers. The tweeters are extremely fast and transparent, and I think only the field coil drivers are able to keep up with them. I am using an Accuphase F25 electronic crossover, and I am using two pairs of 300B differential PP amps for the tweeter and midrange, and a Parasound A23+ ss amp for the bass. The sound is very natural and dynamic, which can be attributed to the field coils, and having no passive crossover. I would love to play with the Line Magnetic replica drivers. I have a friend who collects Western Electric gear. A pair of WE755a in original cabinets had the most gorgeous mid-range.
I have T3.4 and the T1.5 I also have the Line Magnetic. Whilst I love them all for their on distinct character in portraying music. The Classic Audio Loudspeaker to my ears is still a better Speaker over the LM Field Coils.

Its less coloured and more truthful.

The LM3 Field coils are exceptional speakers but they do have a more romantic tone to them whilst this works well with lesser recording some information is lost as a compromise. It really then comes down to personal taste at this level.

The Classic Audio Loudspeaker seriously need good Tube Power Supply the SS power supply John provides are no way doing the speaker any justic.
 
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adrianywu

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I have T3.4 and the T1.5 I also have the Line Magnetic. Whilst I love them all for their on distinct character in portraying music. The Classic Audio Loudspeaker to my ears is still a better Speaker over the LM Field Coils.

Its less coloured and more truthful.

The LM3 Field coils are exceptional speakers but they do have a more romantic tone to them whilst this works well with lesser recording some information is lost as a compromise. It really then comes down to personal taste at this level.

The Classic Audio Loudspeaker seriously need good Tube Power Supply the SS power supply John provides are no way doing the speaker any justic.
I have been thinking about a tube field coil supply, but most of the ones I have seen are very expensive and there is no way of trying them first. I might just build them myself, but I have to settle on a good design. A SS regulated linear PS should have a tighter regulation than a tube regulated supply, and with a lower source impedance. Which parameters of a tube supply do you think are responsible for its better performance ? My system is fully tube based, but with SS regulation and with FET current sinks etc. I am pretty agnostic as far as the SS vs. Tube debate goes, I believe in implementing circuits using the components most suitable for the task.
 
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audioquest4life

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I have been thinking about a tube field coil supply, but most of the ones I have seen are very expensive and there is no way of trying them first. I might just build them myself, but I have to settle on a good design. A SS regulated linear PS should have a tighter regulation than a tube regulated supply, and with a lower source impedance. Which parameters of a tube supply do you think are responsible for its better performance ? My system is fully tube based, but with SS regulation and with FET current sinks etc. I am pretty agnostic as far as the SS vs. Tube debate goes, I believe in implementing circuits using the components most suitable for the task.
I would rather use something that someone else has tested, either tube or SS as well. I am not about to go DIY for this solution. If someone in the Classic Audio Field Coil speakers community is building these better power supplies or if we can be pointed to a solution where we can purchase said power supply, that would be great. Bottom line, i am fine with plug and play as is with the supplied power supply, but, if someone advocates that the sound can be better with a tweak, I would like for that tweak to be somewhat simple tweak and easy to obtain, without me worrying about building a Frankenstein looking power supply that may not perform properly because I tried my hand at DIY. I know my DIY limitations; therefore, I won't change a thing unless another power supply is readily available and I don't have to do anything except for plug and play, and if others are using it as well. Seems to be only two people I read that use aftermarket or DIY power supplies, with Classic Audio Field coil speakers, Atma-sphere is one of them. I will keep watching this thread to see what pans out.
 
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Phantom-Audio

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I honestly cant explain why, I had custom Power block made for the field coil this was solid state whilst it was a big improvement the Tube Power supply just threw a larger more expansive sound stage and slightly sweeter but very musical overall compared to my SS power supply.

John Wolff now has Tube Power supply using Tungar altenative i can get some from LM Customised but John wolff power supply are better built but cost more.
 
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audioquest4life

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I honestly cant explain why, I had custom Power block made for the field coil this was solid state whilst it was a big improvement the Tube Power supply just threw a larger more expansive sound stage and slightly sweeter but very musical overall compared to my SS power supply.

John Wolff now has Tube Power supply using Tungar altenative i can get some from LM Customised but John wolff power supply are better built but cost more.
Sounds good. I will contact John and inquire about his use of the tube power supplies. He is a partial day drive from me. Thanks for the update.
 

DetroitVinylRob

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Looking forward to seeing John Wolff and hearing a tube based Tungar alternative power supply. Hope I could audition a pair as his place is just a short drive from mine. The last we spoke it was still in the development stages.

Wonder if Ralph from Atma-Sphere collaborated on this project or if he has listened to the result?

All good news.
 

ACHiPo

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Feb 22, 2015
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Looking forward to seeing John Wolff and hearing a tube based Tungar alternative power supply. Hope I could audition a pair as his place is just a short drive from mine. The last we spoke it was still in the development stages.

Wonder if Ralph from Atma-Sphere collaborated on this project or if he has listened to the result?

All good news.
I heard John's tube-based power supply when I auditioned his T-1.5 speakers at his house. He claimed much better performance with the tube power supplies than solid state bench supplies, but I only heard the tube power supplies. He was running hot-rodded Novacron amps. The system played the best I've ever heard "So What" especially Coltrane and Adderly on sax. Realistic drums and cymbal dynamics. Also an annoying level of hum and a right-shifted stereo image which John was unable to fix when I was there.
 

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