Iron Coil question
Hi John, I need advice concerning the big iron coil for the Peerless.
I am trying to find an iron coil in Europe and it seams that 18 o 22 mH are sort of standard here. But I did find some Janzen C-coil 20.00mH 5% rdc-0.29 10% wire-1.40/ 800 Watt 8 Ohm and the more expensive: C-coil 20.00mH 5% rdc-0.18 10% wire-1.60/ 1500 Watt/ 8 Ohm.
Would they work?
DaWa
Hi John, I need advice concerning the big iron coil for the Peerless.
I am trying to find an iron coil in Europe and it seams that 18 o 22 mH are sort of standard here. But I did find some Janzen C-coil 20.00mH 5% rdc-0.29 10% wire-1.40/ 800 Watt 8 Ohm and the more expensive: C-coil 20.00mH 5% rdc-0.18 10% wire-1.60/ 1500 Watt/ 8 Ohm.
Would they work?
DaWa
Usable inductors
Hello DaWa
The Manzanita can work well with anything from 16 Mh up to 22 Mh. Sweet spot is 18 to 22. Above 22 no additional advantage. It is best to keep the DCR below .6 ohm or so. Your Janzen selection should work well. The lower DCR may require a slight adjustment of the high pass R2. I would use 5 ohms to start with and if you feel the high end is not as bright as you would like, then try 4.5 ohms. It seems the Latest Vifa's are a bit hotter than the earlier production runs, so it seems 5.0 ohms for R2 and 15-25 ohms for R1 seem to be a better balance for most listeners. Please let us know what ends up working for you. John
Hello DaWa The Manzanita can work well with anything from 16 Mh up to 22 Mh. Sweet spot is 18 to 22. Above 22 no additional advantage. It is best to keep the DCR below .6 ohm or so. Your Janzen selection should work well. The lower DCR may require a slight adjustment of the high pass R2. I would use 5 ohms to start with and if you feel the high end is not as bright as you would like, then try 4.5 ohms. It seems the Latest Vifa's are a bit hotter than the earlier production runs, so it seems 5.0 ohms for R2 and 15-25 ohms for R1 seem to be a better balance for most listeners. Please let us know what ends up working for you. John
I need to pay more attention!
Hey DaWa
You kinda caught me sleeping, forgot you intended to try the SS 2905. Part of my previous post had the Vifa in mind, which of course would not apply directly to the SS 2905.
Can you tell me what about the bass output that you did not expect? Amount, quality, low end extension? How did you have your Mini-DSP set up?
John
Hey DaWa
You kinda caught me sleeping, forgot you intended to try the SS 2905. Part of my previous post had the Vifa in mind, which of course would not apply directly to the SS 2905.
Can you tell me what about the bass output that you did not expect? Amount, quality, low end extension? How did you have your Mini-DSP set up?
John
Well I sort of followed all sugestionds but ended up a little like Rudolf sugested a 1220 lp for the woofer and 1350 hp for the 2905. A little Eq at 100 Hz. Then meassure and adjust the amplification on my bas amplifier so I get a "flat" response. Sounds ok but lacks the "slam". I think what You do in the passive filter is not so easy to replicate in the digital filter. So I will go for the original Vifa design and make a comparisson./Dawa
Finished my Manzanitas. Wow. Sounds great. A little harsh, but everything needs to break in.
First observations: needs some power. My 125 watt per channel amp is keeping up, but it sounds like I need all of it.
I moved them closer to the back wall - 3 feet - sounds more balanced.
Lots of detail and lots of bass. The midrange sounded a little weak at first, but is starting to come out.
Vinyl with my phonoclone 3 is shining big time. The bass is tight on most tracks and the percussion has impact. Vinyl puts my Squeezebox with the rDac to shame.
I think everything will clear up in general with some hours of break-in.
I bow down to the incredible design of the Manzanita. To achieve this quality and sophistication with such a simple design and such inexpensive drivers is amazing.
John
First observations: needs some power. My 125 watt per channel amp is keeping up, but it sounds like I need all of it.
I moved them closer to the back wall - 3 feet - sounds more balanced.
Lots of detail and lots of bass. The midrange sounded a little weak at first, but is starting to come out.
Vinyl with my phonoclone 3 is shining big time. The bass is tight on most tracks and the percussion has impact. Vinyl puts my Squeezebox with the rDac to shame.
I think everything will clear up in general with some hours of break-in.
I bow down to the incredible design of the Manzanita. To achieve this quality and sophistication with such a simple design and such inexpensive drivers is amazing.
John
Inductors
I continue to be really happy with the way my speakers sound (Thanks again John). I have yet to solder everything point to point and was pondering the final layout of the crossover when I notice the leads of the iron core inductor buzzing with vibration. I also happened to also read an article regarding passive crossovers and more specifically behavior of inductors and soaking them (the coils) in varnish to hold the wire in place and eliminate any buzzing and or vibration. Does anyone have any experience or comments with doing this?
I continue to be really happy with the way my speakers sound (Thanks again John). I have yet to solder everything point to point and was pondering the final layout of the crossover when I notice the leads of the iron core inductor buzzing with vibration. I also happened to also read an article regarding passive crossovers and more specifically behavior of inductors and soaking them (the coils) in varnish to hold the wire in place and eliminate any buzzing and or vibration. Does anyone have any experience or comments with doing this?
Thanks John C for the glowing report. Yes, they do need power - that's the trade off for decent bass out of a mid size OB. No free lunch. John B's designs usually have what sounds like a recessed midrange, but don't all measure that way. Maybe were just used to speakers with a midrange bump.
If the Manzanita is harsh, you may need some crossover tuning. John B can jusmp in there with some hints.
If the Manzanita is harsh, you may need some crossover tuning. John B can jusmp in there with some hints.
I grew up with bookshelf speakers, so you may be right that I am biased towards more midrange. The harshness may just be a function of no break in time and that the material I played first, Richard Thompson's Hand of Kindness, is a little harsh sounding with lots of reeds and screaming guitars. The temporary stands were also too high. I cut the wood for the proper height stands, but have not put them together yet. There was no way I could wait for the stands to be done to fire up the new speakers!
I will get some more playing time on the Manzanitas and move them around in different rooms before I start thinking about tweaking the crossovers.
Thanks for all the help from you and the other forum members. I studied many of the pictures in this thread to help with the crossover layout and wiring and it looks like I got it right the first time (something that I am not used to with my marginal DIY skills).
I believe that the "Manzanita" speaker would be substantially improved by replacing the 12" woof with a vertical array of smaller woofer/mids, such as 2 8", 4 8" or 4 6". Xmax is the most important spec for OB drivers for mid and bass. The narrower the output horizontally, the more clear the time based stereo imaging cues in the lower midrange, and the more spread out vertically the emission, the more the room reflection comb filter effects will be likely to be largely filled in by other comb filter reflection mechanisms (which will have differing amounts of delay relative to a given listener location, and therefore cancellation frequencies). Also, where the tweeter crosses in, the dispersion will change dramatically and leave off axis locations in a bad way. Off axis, you'll have a large increase in acoustic energy at the frequency where the tweeter comes in. At the freqs that the ear is most sensitive to (1kHZ - 6kHZ). A 12 inch starts getting pretty directional at around 500HZ. 5 inch drivers are good to about 2kHZ. I love OB speakers. The only problem with them is that for psycho-acoustic reasons, they need to be at least 3 ft away from any walls, and not all wives appreciate that. Plus if others will be seated way off axis, they will get a thinner lower mid and bass energy.
Some of you might be interested in the OB system I designed and built. I call it the Aurium Waveguide. Triamp'd, 4 pole Linkwitz/Riley active crossover/OB EQ.
http://www.spiritone.com/~rob_369/audio/AuriumWaveguide2010.htm
Some of you might be interested in the OB system I designed and built. I call it the Aurium Waveguide. Triamp'd, 4 pole Linkwitz/Riley active crossover/OB EQ.
http://www.spiritone.com/~rob_369/audio/AuriumWaveguide2010.htm
Bob, i don't think so. Ok if you talk about the dome version...
But with the Vifa version, the only thing I see is to add a tweeter but i trust john's ears. This project is well done
This 3" compensates the bad directivity of the 12" above 500Hz. The 12" does it jobs in the low midrange and bass. Finally you a have a small compact project.
Go to lower diameter will give you a bigger and more expensive speaker.
And the problem with small surface driver is you run into other distortion problem in the low frequency. A 6.5" is not done for bass... 8" ok but in a large baffle is not very easy to work with... Try to do a passive version of your line array speaker (and i have seen you add a subwoofer).
But with the Vifa version, the only thing I see is to add a tweeter but i trust john's ears
. This project is well done This 3" compensates the bad directivity of the 12" above 500Hz. The 12" does it jobs in the low midrange and bass. Finally you a have a small compact project.
Go to lower diameter will give you a bigger and more expensive speaker.
And the problem with small surface driver is you run into other distortion problem in the low frequency. A 6.5" is not done for bass... 8" ok but in a large baffle is not very easy to work with... Try to do a passive version of your line array speaker (and i have seen you add a subwoofer).
Hey, if the Manzanita guys are happy, that's all that counts. Going to a 3 inch mid/tweeter will be a better dispersion transition than if he had a 1 inch dome. I look at and listen to my speakers every day, and I hope to have them for 10-20 years+, so I hate to see someone build a cheap version of something that they might not care for in a few months. I hope I didn't come off as rude. I am just trying to help motivate fellow hobbyists to go a little further, and have something they can really be proud of and enjoy for many years to come.
No worries, Bob. There's more than one way to skin an Open Baffle -this is just one way.
And the Manzanita is not a "cheap version of something" that you'll regret later. It's a lovely, well rounded speaker with decades of experience (success and failure) behind it. Yes, you can do better, but you'll have to go bigger. For its size, I don't know much of anything that's more fun to listen to.
And the Manzanita is not a "cheap version of something" that you'll regret later. It's a lovely, well rounded speaker with decades of experience (success and failure) behind it. Yes, you can do better, but you'll have to go bigger. For its size, I don't know much of anything that's more fun to listen to.
Bob
Thanks for sharing your very interesting project! Always great to see others get out the saw and translate their personal designs into reality. As for improving the Manzanita, like all designs it has several flaws. Many small compromises were made to keep the project as simple mechanically and electrically as possible. I was determined to make a plug and play speaker that just about anyone could build with simple tools a majority of the public own. Keeping the price down and limiting the components required to those available as widely as possible also influenced design decisions.
Your project is a much more sophisticated, complex and higher cost design that does address a couple of the Mazanita's compromises. It would be fun to audition it and get a feel for what it does well. Have you demonstrated your creations anywhere? Always great to share and get fresh opinions - input.
John
Thanks for sharing your very interesting project! Always great to see others get out the saw and translate their personal designs into reality. As for improving the Manzanita, like all designs it has several flaws. Many small compromises were made to keep the project as simple mechanically and electrically as possible. I was determined to make a plug and play speaker that just about anyone could build with simple tools a majority of the public own. Keeping the price down and limiting the components required to those available as widely as possible also influenced design decisions.
Your project is a much more sophisticated, complex and higher cost design that does address a couple of the Mazanita's compromises. It would be fun to audition it and get a feel for what it does well. Have you demonstrated your creations anywhere? Always great to share and get fresh opinions - input.
John
John, Here in Portland Oregon we have an informal Audiophile club called the Oregon Triode Society. We get together monthly at a restaurant for open to the public meetings for general discussions and some show and tell. On other occasions we all go to someone's house and see their system. The club originators are tube addicts, but most of us use transistors as well or instead. Right now several of us are trying to finish up projects for another show and tell. A few of us have actual products that we make and sell, but it's mostly just a bunch of hobbyists sharing their passion for great audio reproduction. What part of the country are you in?
Of which I am a member, believe it or not. Or more accurately put, I still get the emails. I miss the meetings.
I've finished my manzanitas now. I unwound a .80 mh coil to about .40 and ran it in series with the 2.00 mh. Used a 15 ohm resistor with this and it tames the harshness I was hearing ( could be my tinitis ). So only a change in the tweet inductor.
Listened and enjoyed them last night along with some red wine. Marvelous to have some real bass in the house. Also the open and airy nature of an OB. Also clear sound at higher levels. I've got them abput 3' off the wall and 4' from the side walls - placement does matter with these. I made some stands out of mdf so they are at a good height.
There is a part of the midrange that is subdued but I only notice this on some very familiar recordings. I think this could be fixed pretty easily. I might try adding a second tweet in series with the first and roll the highs off it with a 68 uf electrolytic across it. Would locate it just above the first one on the baffle. This would fill in the mids some I think. The tweets are so cheap it could'nt hurt to try.
So my third speaker project is finished for the most part. Learned a bunch more along the way and also am noodling around the next project.
Listened and enjoyed them last night along with some red wine. Marvelous to have some real bass in the house. Also the open and airy nature of an OB. Also clear sound at higher levels. I've got them abput 3' off the wall and 4' from the side walls - placement does matter with these. I made some stands out of mdf so they are at a good height.
There is a part of the midrange that is subdued but I only notice this on some very familiar recordings. I think this could be fixed pretty easily. I might try adding a second tweet in series with the first and roll the highs off it with a 68 uf electrolytic across it. Would locate it just above the first one on the baffle. This would fill in the mids some I think. The tweets are so cheap it could'nt hurt to try.
So my third speaker project is finished for the most part. Learned a bunch more along the way and also am noodling around the next project.