Field Coils for Audio Systems

[dcathro]

I have a few rod Coleman power supplies to build and try out, they are supposed to be nice.

Congratulations on your project, it looks like a lot of fun.

I have just finished building a pair of the Rod Coleman power supplies for use on my Supravox 215s. They replaced a pair of Mastech1505D lab supplies that I had previously modified.





The Coleman's are a significant improvement and I am in the process of building a pair to try on my WVL bass drivers





I am currently powering my bass drivers with large HP Agilent power supplies, so this will be interesting.

 

[Superchunk]

Well, someone else bought the drivers. Kind of sucks, particularly as I was first in line and we had basically sorted it out and I gave the let's do it...then wait a few days and "whoops sold". I dunno, I don't play like that but that's just me. Of course now I really want them

Oh well, more money for other stuff...and I believe treehause that the AE dipole will probably give me everything I need whenever I want to pull the trigger on those.

 

[Superchunk]

Congratulations on your project, it looks like a lot of fun.

I have just finished building a pair of the Rod Coleman power supplies for use on my Supravox 215s. They replaced a pair of Mastech1505D lab supplies that I had previously modified.

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The Coleman's are a significant improvement and I am in the process of building a pair to try on my WVL bass drivers

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I am currently powering my bass drivers with large HP Agilent power supplies, so this will be interesting.

Ah nice to see someone else working on the same thing. My current power supplies (punny) are made by the driver manufacturer so I'll be curious to see if the Coleman sound better.

I notice you're using one fancy resistor and one simple, is that because of what you had around or is the one position more impactful?

 

[songeraudio]

Well, someone else bought the drivers. Kind of sucks, particularly as I was first in line and we had basically sorted it out and I gave the let's do it...then wait a few days and "whoops sold". I dunno, I don't play like that but that's just me. Of course now I really want them

Oh well, more money for other stuff...and I believe treehause that the AE dipole will probably give me everything I need whenever I want to pull the trigger on those.

Ah, I am sorry to hear that - I confess, I was a little jealous that you were going to get your hands on a pair of those for such a great price.

On the bright side, you're going to like the AE dipole woofers a lot - they perform beautifully and are very well-made.

 

[Superchunk]

Ah, I am sorry to hear that - I confess, I was a little jealous that you were going to get your hands on a pair of those for such a great price.

On the bright side, you're going to like the AE dipole woofers a lot - they perform beautifully and are very well-made.

Yeah I had got pretty excited about how it was all going to fit together, but I don't get the impression the AE play second best to much for dipole...and no $500-1000 power supplies and associated cables so...self sooth self sooth.

Also, I do have an unopened pair of field coil midbass sitting on my desk so life's pretty good

 

[LanschePlasmaGuy]

Sorry to hear about your Kanzen sale falling through.

A quick spoiler - the Palladin's have been on for what is now day 3 and initial impressions are - they are stunning. Fabulous slam, hit and beautiful tone. They give the feeling of fantastic weight (more like what I would expect from my 18 inch JBL 4345's in many ways) and seem to be a beautiful blend with the Rullit Super Aero 9 driver getting out of the way and not muddying the lower notes of the Rullits at all.

The best quality is the combination of low bass weight which I was not expecting in a small open baffle and when looking at what is a very light responsive paper cone is how effortless they are. Really "fast" (sorry if that's an annoying term to some) but absolutely relaxed at the same time. In that way they are more akin to what you hear from the lower registers of a live unamplified instrument. They have a very natural non-mechanical sound.

Please take this short impression above as a first brief impression. It's only been three days and as we all know when playing with new toys we can get pretty excited initially and get hyper focused on the positives.

I'll be doing some measurements and more experiments soon. I still haven't even played with the power supply yet (set at around 12 volts / 2 amps) to tune the sound and the drivers are very much breaking in (maybe 12 hours so far).

But my feeling so far is they are going to be absolutely wonderful.

To add a little more for context bass options this room has hosted have included: Shahinian Diapason Double Eagle bass modules, Shahinian Obelisks, Shahinian Obelisks with the Shahinian double eagle bass modules (that was pretty insane), the 18 inchers on my JBL 4345's, two different variants of Klipsch Belle based bass horns (using the recommended and supposedly best option Crites drivers) and the 18 inch bass driver H frame (which were designed by Lynn T Olsen's on one of his threads).

Interestingly all of those bass options above have needed room eq to get the best out of them and to smooth out room nodes and such (and in the case of the Belle based bass horn bins, to also apply EQ so they went pretty flat to around 33 hz in room. The 18's in the H frame open baffle design needed a fair amount of boost to do provide bass to about 25 hz. I initially started using the Kanzen Palladin field coils in the open baffle with the existing eq settings I'd used for the 18 inch H frame open baffle drivers. After some adjustments to get the bass working from the Palladins so I was happy I ended up taking more and more of the eq options out (and all the bass boost). For whatever reason they sounded best with no eq and no bass boost. They seem to be interacting less negatively in my room than the other bass options I have used.

LPG

 

[Superchunk]

Amazing, sounds fantastic. Happy for you sad for me. Really sounds like the whole package as far as what one would hope for in a bass driver. Have fun man

 

[the sound of Tao]

Sorry to hear about your Kanzen sale falling through.

A quick spoiler - the Palladin's have been on for what is now day 3 and initial impressions are - they are stunning. Fabulous slam, hit and beautiful tone. They give the feeling of fantastic weight (more like what I would expect from my 18 inch JBL 4345's in many ways) and seem to be a beautiful blend with the Rullit Super Aero 9 driver getting out of the way and not muddying the lower notes of the Rullits at all.

The best quality is the combination of low bass weight which I was not expecting in a small open baffle and when looking at what is a very light responsive paper cone is how effortless they are. Really "fast" (sorry if that's an annoying term to some) but absolutely relaxed at the same time. In that way they are more akin to what you hear from the lower registers of a live unamplified instrument. They have a very natural non-mechanical sound.

Please take this short impression above as a first brief impression. It's only been three days and as we all know when playing with new toys we can get pretty excited initially and get hyper focused on the positives.

I'll be doing some measurements and more experiments soon. I still haven't even played with the power supply yet (set at around 12 volts / 2 amps) to tune the sound and the drivers are very much breaking in (maybe 12 hours so far).

But my feeling so far is they are going to be absolutely wonderful.

To add a little more for context bass options this room has hosted have included: Shahinian Diapason Double Eagle bass modules, Shahinian Obelisks, Shahinian Obelisks with the Shahinian double eagle bass modules (that was pretty insane), the 18 inchers on my JBL 4345's, two different variants of Klipsch Belle based bass horns (using the recommended and supposedly best option Crites drivers) and the 18 inch bass driver H frame (which were designed by Lynn T Olsen's on one of his threads).

Interestingly all of those bass options above have needed room eq to get the best out of them and to smooth out room nodes and such (and in the case of the Belle based bass horn bins, to also apply EQ so they went pretty flat to around 33 hz in room. The 18's in the H frame open baffle design needed a fair amount of boost to do provide bass to about 25 hz. I initially started using the Kanzen Palladin field coils in the open baffle with the existing eq settings I'd used for the 18 inch H frame open baffle drivers. After some adjustments to get the bass working from the Palladins so I was happy I ended up taking more and more of the eq options out (and all the bass boost). For whatever reason they sounded best with no eq and no bass boost. They seem to be interacting less negatively in my room than the other bass options I have used.

LPG

That’s really good to hear LPG and many thanks for the update. I’ve been shortlisting options on OB bass and had moved away from going field coil bass drivers because of field coil being a potentially less ideal in bass applications especially in an OB environment. Really encouraging to hear how it’s going for you.

I know it’s inevitably controversial but if you were open to sharing video of where it’s sounding at the moment that’d be fantastic but appreciate if that’s not a thing for you. The updates are valuable and completely interested in how this ultimately works out for you. Great to see you exploring this option.

 

[dcathro]

Ah nice to see someone else working on the same thing. My current power supplies (punny) are made by the driver manufacturer so I'll be curious to see if the Coleman sound better.

I notice you're using one fancy resistor and one simple, is that because of what you had around or is the one position more impactful?

I am sure that the Coleman regulators will sound better.

I just happened to have the right value 1.8R in the Supreme resistors.

 

[Treehaus Audiolab]

I assume you are using AE woofers that are designed for open baffle, whereas the Supravox is more suited to a reflex alignment.

I don't think that my WVL bass drivers would be happy in an open baffle either.

I agree here, it was at the slight detriment to the Supravox in this arrangement.

Ken Songer.. field coil open baffle woofer please

 

[Treehaus Audiolab]

I am sure that the Coleman regulators will sound better.

I just happened to have the right value 1.8R in the Supreme resistors.

Coleman regulator for field coil supply... that is an interesting use-case. We use them on filaments.. they are very nice pieces. Id make sure that however you are attaching the supply to the driver is robust (something locking) because Im not sure how the regulator will react if it suddenly loses connection. (I blew out of CCS early on in a similar situation)

 

[Superchunk]

Coleman regulator for field coil supply... that is an interesting use-case. We use them on filaments.. they are very nice pieces. Id make sure that however you are attaching the supply to the driver is robust (something locking) because Im not sure how the regulator will react if it suddenly loses connection. (I blew out of CCS early on in a similar situation)

Thanks for pointing that out, I intended to use locking XLR, sounds like I should stick with that.

Nice to hear you like them - heakes a FC specific one but it's not up on the site anywhere.

 

[dcathro]

Some nice pics of the higher end Audio Note (UK) field Coils in this German review.

 

[GroovySauce]

I recently acquired a used pair of Voxativ AC-X with the N1 PS. They are being used in Pure Audio Project Quintet 15s. I’m blown away by the step up from the Voxativ 1.6.

I’m currently looking at power supply options.

The N1 has extremely limited adjustability 11.1-12.3v.

I bought a pair of https://www.amazon.com/dp/B09YSJQWRG?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1 to use as a temporary solution.

I found my preferred listening voltage between 8.5-9.5v Still dialing it in, 9-9.2 is where I’m narrowed it down to.

If the Songer Audio power supplies went down to 8v they would be at the top of the list.

Is it a bad idea to have one power supply supplying both drivers?

What companies make good adjustable power supplies? For now I’m interested in SS models as I want to keep cost on the lower side.

Anyone run Acopian power supplies?

Thank you much!

 

[dcathro]

I recently acquired a used pair of Voxativ AC-X with the N1 PS. They are being used in Pure Audio Project Quintet 15s. I’m blown away by the step up from the Voxativ 1.6.

I’m currently looking at power supply options.

The N1 has extremely limited adjustability 11.1-12.3v.

I bought a pair of https://www.amazon.com/dp/B09YSJQWRG?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1 to use as a temporary solution.

I found my preferred listening voltage between 8.5-9.5v Still dialing it in, 9-9.2 is where I’m narrowed it down to.

If the Songer Audio power supplies went down to 8v they would be at the top of the list.

Is it a bad idea to have one power supply supplying both drivers?

What companies make good adjustable power supplies? For now I’m interested in SS models as I want to keep cost on the lower side.

Anyone run Acopian power supplies?

Thank you much!

Congratulations on your acquisition!

I am sure that the Voxativs are stunning.

Regarding power supplies, If you are competent with a soldering iron, I would suggest building some Rod Coleman supplies like I did. He charges very little for the kits, but you need to be able to build it, supply the power transformers, capacitors, heat sinks and put it in a box.

I built mine with very high quality parts, and it cost about US $250 for each supply.

If this is not your thing, Wolf Von Langa sells a similar Constant Current Supply that will drive a pair of field coils, but it is quite expensive.

 

[GroovySauce]

@dcathro Thank you.

I looked for the Rod Coleman field coil power supply and couldn't find anything. I found a filament kit, no field coil kit. Can you share a link?

 

[dcathro]

@dcathro Thank you.

I looked for the Rod Coleman field coil power supply and couldn't find anything. I found a filament kit, no field coil kit. Can you share a link?

He doesn't advertise it for field coils, it is basically a modification of the filament regulator. This is the same approach that WVL and Audio Note are using. I can verify that it works better than a lab supply.

His website is here

He is very supportive via email.

 

[cal3713]

Only the best interactions with Rod on my end as well. Encourage him to finish up those regulators for eml 20a's while you're at it. Haha.

 

[Treehaus Audiolab]

Ron is good people and that’s a great use for his Coleman regulators

 

[GroovySauce]

Thank you all. I've contacted Rod and am going to order two of his kits.