Hello DIYers,
For along time i have been a lover of the OHM Acoustics speaker company. I was wondering if anyone on this site had heard of them and was wondering what there thoughts were on the company.
Another question is, has anyone tried to replicate there landmark speaker the Walsh F?
I know the speaker to begin with was particularly difficult to build. It was also fuzzy. But if you were able to set up the WALSH "F's" just right, they sounded like a million bucks. some saying it is the best speaker ever made.
I was wondering if anyone was able to replicate this unusual design and make a speaker using the WALSH technology.
Thanks.
For along time i have been a lover of the OHM Acoustics speaker company. I was wondering if anyone on this site had heard of them and was wondering what there thoughts were on the company.
Another question is, has anyone tried to replicate there landmark speaker the Walsh F?
I know the speaker to begin with was particularly difficult to build. It was also fuzzy. But if you were able to set up the WALSH "F's" just right, they sounded like a million bucks. some saying it is the best speaker ever made.
I was wondering if anyone was able to replicate this unusual design and make a speaker using the WALSH technology.
Thanks.
The standing joke was that it took 200W to get the original Walsh speakers to make sound and 201W to blow them up.
The Ohm versions were poor copies. They were basically a one trick pony. They could do that weird where's-the-speaker imaging thing, but the sound quality was sad compared to other speakers. The shop I worked for bought something like two dozen pairs of the stupid things and we could hardly give them away. For all I know, they still have a pair or two.
The basic idea is simple enough--just turn a driver face down into a box so that you're listening to the back of the cone with no cabinetry. It images well, and is close to omnidirectional. So far, so good. The problem is the frequency extremes. The way they got anything like reasonable frequency response out of the original Walsh was to vary the makeup of the cone from (as I recall) metal at the voice coil to paper at the surround. Each ring of material had to be bonded to the next quite carefully. Note that the metal and bonding agents increased the mass of the cone considerably, and transients suffered as a result.
The Ohm speakers used really cheap drivers and treated them.
Of the two approaches, the Ohm strategy is going to be more practical to the average DIYer. I'd reccommend getting a case of really cheap "buyout" paper cone drivers from Parts Express--the 99 cent specials--and experiment with different treatments. Your goal is controlled cone breakup, which is a difficult horse to ride. Once you set different parts of the cone in motion, things are going to get complicated fast.
Suggestions for paper treatments: rubber cement, super glue, varnish, polyurethane, etc. Also consider the careful application of water to loosen up the paper fibers and make the cone more floppy. Your goal is to have the cone as stiff as possible up near the voice coil so that it acts like a tweeter. As the frequencies decrease, you'll need to assign more cone area to radiate.
You'll end up trashing a lot of speakers in the beginning, which is why I suggested starting with really cheap ones.
On the other hand, you might just decide that you like the sound of an ordinary driver upside-down, in which case you're done.
Grey
The Ohm versions were poor copies. They were basically a one trick pony. They could do that weird where's-the-speaker imaging thing, but the sound quality was sad compared to other speakers. The shop I worked for bought something like two dozen pairs of the stupid things and we could hardly give them away. For all I know, they still have a pair or two.
The basic idea is simple enough--just turn a driver face down into a box so that you're listening to the back of the cone with no cabinetry. It images well, and is close to omnidirectional. So far, so good. The problem is the frequency extremes. The way they got anything like reasonable frequency response out of the original Walsh was to vary the makeup of the cone from (as I recall) metal at the voice coil to paper at the surround. Each ring of material had to be bonded to the next quite carefully. Note that the metal and bonding agents increased the mass of the cone considerably, and transients suffered as a result.
The Ohm speakers used really cheap drivers and treated them.
Of the two approaches, the Ohm strategy is going to be more practical to the average DIYer. I'd reccommend getting a case of really cheap "buyout" paper cone drivers from Parts Express--the 99 cent specials--and experiment with different treatments. Your goal is controlled cone breakup, which is a difficult horse to ride. Once you set different parts of the cone in motion, things are going to get complicated fast.
Suggestions for paper treatments: rubber cement, super glue, varnish, polyurethane, etc. Also consider the careful application of water to loosen up the paper fibers and make the cone more floppy. Your goal is to have the cone as stiff as possible up near the voice coil so that it acts like a tweeter. As the frequencies decrease, you'll need to assign more cone area to radiate.
You'll end up trashing a lot of speakers in the beginning, which is why I suggested starting with really cheap ones.
On the other hand, you might just decide that you like the sound of an ordinary driver upside-down, in which case you're done.
Grey
Sorry I almost forgot, here is some constructive input
http://www.audiodesignguide.com/full/conus1.html
/ Mikael
http://www.audiodesignguide.com/full/conus1.html
/ Mikael
Interesting website you've got there. I hadn't envisioned actually disassembling the driver, since that leads into cone/voil coil alignment difficulties.
That said, here's a trick that will help keep the voice coil aligned. Once you've got the center dome off, you have access to the inside gap between the coil former and the center pole of the magnet. Take a piece of paper--ordinary notebook paper will do--and wrap it into a tube the same diameter as the gap. The goal is to wrap enough turns of the paper onto your tube that it fits into the gap quite snugly. You may have to try two or three times to get the right thickness to fill the gap, but don't worry about it, notebook paper is cheap. This gives two benefits. One is that it evenly spaces the voice coil in the gap so that it doesn't rub when you're done. The other is that it will hold the voice coil relatively still while you're gluing things to it.
Obviously, you'll need to remove the paper tube before trying out your new driver.
Note that removing the old cone and replacing it with a new one made from new experimental materials will change the effective mass and stiffness of the cone. As such, the T-S parameters go out the window. You'll need to measure the new T-S parameters of the driver yourself, then build a cabinet to suit those numbers, not the old ones.
Grey
That said, here's a trick that will help keep the voice coil aligned. Once you've got the center dome off, you have access to the inside gap between the coil former and the center pole of the magnet. Take a piece of paper--ordinary notebook paper will do--and wrap it into a tube the same diameter as the gap. The goal is to wrap enough turns of the paper onto your tube that it fits into the gap quite snugly. You may have to try two or three times to get the right thickness to fill the gap, but don't worry about it, notebook paper is cheap. This gives two benefits. One is that it evenly spaces the voice coil in the gap so that it doesn't rub when you're done. The other is that it will hold the voice coil relatively still while you're gluing things to it.
Obviously, you'll need to remove the paper tube before trying out your new driver.
Note that removing the old cone and replacing it with a new one made from new experimental materials will change the effective mass and stiffness of the cone. As such, the T-S parameters go out the window. You'll need to measure the new T-S parameters of the driver yourself, then build a cabinet to suit those numbers, not the old ones.
Grey
OHM Walsh "CLS" Driver
Thank you for the quick replies.
From the way it sounds the Walsh F driver was an under designed speaker. I know that OHM still manufactures a Walsh model but they now use different technology. They are suppose to be better than the origional. They can handle more power, more sensitive, play louder, have better imaging, and are easier to drive. I have been told they arn't particularly hard to drive but thrive when they have good power. The problem with the "new" OHM Walsh's from was that they lacked microdynamics. However after reading a review on a pair of Blue Circle Audio BC8 amplifiers the impression of the Ohm Walsh was changed. This amplifier took ahold of the speaker and was able to transform them into a marvelous speaker. The person who reviewed them though the BC8's and the Walsh 300 MK2's were the best pairing of speakers and amps he had ever heard in the 12k price range. the speakers themselves cost roughly 4k with the amps around 8k.
Has anyone heard the Ohm's current Crop of Walsh speakers. Has anyone tryied to replicate or modifiy them? Are the new designs better than the origional?
http://ohmspeakers.com/CLSDbig.gif[/URL]
Thank you,
Microwalsh
Thank you for the quick replies.
From the way it sounds the Walsh F driver was an under designed speaker. I know that OHM still manufactures a Walsh model but they now use different technology. They are suppose to be better than the origional. They can handle more power, more sensitive, play louder, have better imaging, and are easier to drive. I have been told they arn't particularly hard to drive but thrive when they have good power. The problem with the "new" OHM Walsh's from was that they lacked microdynamics. However after reading a review on a pair of Blue Circle Audio BC8 amplifiers the impression of the Ohm Walsh was changed. This amplifier took ahold of the speaker and was able to transform them into a marvelous speaker. The person who reviewed them though the BC8's and the Walsh 300 MK2's were the best pairing of speakers and amps he had ever heard in the 12k price range. the speakers themselves cost roughly 4k with the amps around 8k.
Has anyone heard the Ohm's current Crop of Walsh speakers. Has anyone tryied to replicate or modifiy them? Are the new designs better than the origional?
http://ohmspeakers.com/CLSDbig.gif[/URL]
Thank you,
Microwalsh
ohm F + DDD driver
Hello,
I heard both:
Ohm F nice but slow, the driver is an 38cm Bass with a heavy
membran weight.
The DDD with a Horn is my solution:
http://www.hm-moreart.de/6.htm
The best room impression, fast and the bass very tight.
Hello,
I heard both:
Ohm F nice but slow, the driver is an 38cm Bass with a heavy
membran weight.
The DDD with a Horn is my solution:
http://www.hm-moreart.de/6.htm
The best room impression, fast and the bass very tight.
Walsh tweeter
I was under the impression that the walsh tweeter first arrived comercially in the original Infinity Monitor. An icecreamcone turned upside down on top af a large walnut cabinet from 1972.
That tweeter was, as far as i remember, similar in shape to german physics but only 4-5" tall and a pure hf unit. The cone, dont know what it was made of, was enclosed in a perforated aluminium case of the same shape. The only pair i´ve heard of arriving to Sweden in working order i was given an opportunity to listen to and really liked it. This was a detailed and very "fast" tweeter, ambience varied a lot with placement which is natural for 360 dispersion. PLS observe that this was 30 years ago and think the amp was ARC D76. Still: as a tweeter, good idea, the original sales leaflet for the Infinity monitor i think describes the conematerial as mylar- real DIY teritory!
I was under the impression that the walsh tweeter first arrived comercially in the original Infinity Monitor. An icecreamcone turned upside down on top af a large walnut cabinet from 1972.
That tweeter was, as far as i remember, similar in shape to german physics but only 4-5" tall and a pure hf unit. The cone, dont know what it was made of, was enclosed in a perforated aluminium case of the same shape. The only pair i´ve heard of arriving to Sweden in working order i was given an opportunity to listen to and really liked it. This was a detailed and very "fast" tweeter, ambience varied a lot with placement which is natural for 360 dispersion. PLS observe that this was 30 years ago and think the amp was ARC D76. Still: as a tweeter, good idea, the original sales leaflet for the Infinity monitor i think describes the conematerial as mylar- real DIY teritory!
It's not uncommon for reviewers to work themselves into a frenzy over whatever they're listening to...after all, it's what they're paid to do.
Take the review with a grain of salt.
Incidentally, you'll rarely find a product that is acknowledged to be worse than its predecessor; they're always new & improved. It's just marketing.
About the only thing the Walsh/Ohm speakers are good for is being omni-directional. They throw a very wide, deep, but imprecise image. As such, they sound very different from 'normal' speakers and have a lot of wow factor. Unfortunately, they get old quickly because they don't do other things very well.
It's a cool idea, but there are too many factors weighing against it for the concept to ever become more than a niche product.
Grey
Take the review with a grain of salt.
Incidentally, you'll rarely find a product that is acknowledged to be worse than its predecessor; they're always new & improved. It's just marketing.
About the only thing the Walsh/Ohm speakers are good for is being omni-directional. They throw a very wide, deep, but imprecise image. As such, they sound very different from 'normal' speakers and have a lot of wow factor. Unfortunately, they get old quickly because they don't do other things very well.
It's a cool idea, but there are too many factors weighing against it for the concept to ever become more than a niche product.
Grey
Re: Walsh tweeter
My father has a pair of these Infinity Monitors. At one time they were repaired by Infinity and one of the walsh drivers was replaced. They are both different. One is a mylar type material, the other apears to be thin aluminum. I can take pictures of them next week if you want.
Mike
ingvar ahlberg said:
My father has a pair of these Infinity Monitors. At one time they were repaired by Infinity and one of the walsh drivers was replaced. They are both different. One is a mylar type material, the other apears to be thin aluminum. I can take pictures of them next week if you want.
Mike
radial loudspeakers
If you wish to make one look no further for inspiration than Steve
Deckert Radial Thats exactly what he did and did it well enough to
offer it as a finished speaker! Steve is a remarkable"newtonian"
Type guy . Very imaginative! Check THIS out! http://www.decware.com/radials/radials.htm
If you wish to make one look no further for inspiration than Steve
Deckert Radial Thats exactly what he did and did it well enough to
offer it as a finished speaker! Steve is a remarkable"newtonian"
Type guy . Very imaginative! Check THIS out! http://www.decware.com/radials/radials.htm
The Ohm F's are far superior to the newer versions, although they do have some problems.
The originals are very low impedence and low sensitivity, although there aren't too many drivers that can compare with the quality of sound (if any).
Granted, everthing is relative, and if you listen to Heavy Metal or Hip Hop , these aren't for you.
The new Ohm "walsh" drivers are pretty trashy, period. Tons of basket interference , monopole tweeter, metal screen around drivers......YUCK. Of course they claim to be better than the originals , how else would they sell them ? That's called marketing , and it is very often on the borderline of lying.
Just my thoughts , for what they're worth.
Nihilist
The originals are very low impedence and low sensitivity, although there aren't too many drivers that can compare with the quality of sound (if any).
Granted, everthing is relative, and if you listen to Heavy Metal or Hip Hop , these aren't for you.
The new Ohm "walsh" drivers are pretty trashy, period. Tons of basket interference , monopole tweeter, metal screen around drivers......YUCK. Of course they claim to be better than the originals , how else would they sell them ? That's called marketing , and it is very often on the borderline of lying.
Just my thoughts , for what they're worth.
Nihilist
Hello all:
I'm a long time Ohm loudspeaker owner, since the early 90's. My reference was the Walsh 5 for several years. The criticisms and shortcomings of the new Ohms mentioned here I've read often previously. Loudspeaker taste is fairly subjective, and some don't care for the "omni" presentation. Personally, the Ohm Walsh loudspeakers are in a class by themselves in their ability to disappear and present the music very close to live sound. Now the Walsh 5 was not perfect:
1. the midrange was polite; I found myself wanting more detail.
2. the bass was fabulously extended and powerful, but not the tightest alignment.
I wrote a review of the Walsh 5's some years back, so I won't rehash that (review #12):
http://www.audioreview.com/mfr/ohm/floorstanding-speakers/PRD_120287_1594crx.aspx#review0
I upgraded to the latest design driver, the Walsh 5 series 3, several months ago. Let me say that John Strohbeen has addressed all of the shortcomings of the original design, in spades. The bass is just incredible: flat to 20 Hz, extremely well damped and free of audible distortion. The midrange is incredible: oodles of detail, air, microdynamics. Of course, the imaging and soundstaging are nonpareil. And, these Walsh energize my entire listening room and have amazingly unrestrained dynamics and power. To listen to a well -recorded symphony orchestra at full tilt is major goosebumps experience. I reviewed the new driver here (review #1):
http://www.audioreview.com/mfr/ohm/floorstanding-speakers/PRD_120287_1594crx.aspx
To those who claim that the new designs utilizing the supertweeter do not produce the magic and purity of the prototypical Walsh F, I must say that I am very skeptical (but, I have never heard the Walsh Fs). The new Ohm Walsh 5's sound nearly perfect to my ears (I am an ex-amateur classical musician - live acoustic music is my reference). Building a full-range single driver omni is very difficult, and requires sacrificing efficiency. Alos, I do not believe that comparable sound quality cannot be achieved using a sufficiently high crossover point with gentle first order high pass filter for the tweeter. If fact, I have built several experimental loudspeaker drivers and complete loudspeakers using the Walsh inverted cone alignment. My single driver designs were very difficult and time consuming in construction and refinement of the cone/magnet assembly. And yes, thay sounded wonderful. But, I then decided to build some loudspeakers using the modern approach with conventional woofers turned upside down crossed over to a supertweeter. The key here was figuring out how to modify the woofer cone to behave like a bending wave converter. I ultimately came up with a modification that is easily applied, reproducible and consistent. When the modified woofer is run full range (straight line in) and is crossed over to a 1" soft dome tweeter of premium by not overly-expensive top shelf quality (chosen for it's very low Fs=800 Hz, 100W RMS) crossed over in a first order 6 dB/octave slope at 8 KHz (so that the tweeter is hardly taxed under any reasonable listening levels). the result has been a loudspeaker of surpassing fidelity. These loudspeakers are just beautiful sounding, having all the best qualities of an omni. And yes, the midrange detail is Quad-like, electrostat, clean. The key is the monopole tweeter - the controlled directivity above 10 kHz is superior to a full omni radiation. All who have heard these speakers are awe-struck. What is really amazing is how inexpensive and easy they are to built: woofer (with hand-applied mods), tweeter, one good quality polypropylene cap, solid core copper wiring throughout, and the cabinets (I used cardboard tubes) - that's all there is per speaker. One of these days, I should drawn up the plans and post them on line.
I'm a long time Ohm loudspeaker owner, since the early 90's. My reference was the Walsh 5 for several years. The criticisms and shortcomings of the new Ohms mentioned here I've read often previously. Loudspeaker taste is fairly subjective, and some don't care for the "omni" presentation. Personally, the Ohm Walsh loudspeakers are in a class by themselves in their ability to disappear and present the music very close to live sound. Now the Walsh 5 was not perfect:
1. the midrange was polite; I found myself wanting more detail.
2. the bass was fabulously extended and powerful, but not the tightest alignment.
I wrote a review of the Walsh 5's some years back, so I won't rehash that (review #12):
http://www.audioreview.com/mfr/ohm/floorstanding-speakers/PRD_120287_1594crx.aspx#review0
I upgraded to the latest design driver, the Walsh 5 series 3, several months ago. Let me say that John Strohbeen has addressed all of the shortcomings of the original design, in spades. The bass is just incredible: flat to 20 Hz, extremely well damped and free of audible distortion. The midrange is incredible: oodles of detail, air, microdynamics. Of course, the imaging and soundstaging are nonpareil. And, these Walsh energize my entire listening room and have amazingly unrestrained dynamics and power. To listen to a well -recorded symphony orchestra at full tilt is major goosebumps experience. I reviewed the new driver here (review #1):
http://www.audioreview.com/mfr/ohm/floorstanding-speakers/PRD_120287_1594crx.aspx
To those who claim that the new designs utilizing the supertweeter do not produce the magic and purity of the prototypical Walsh F, I must say that I am very skeptical (but, I have never heard the Walsh Fs). The new Ohm Walsh 5's sound nearly perfect to my ears (I am an ex-amateur classical musician - live acoustic music is my reference). Building a full-range single driver omni is very difficult, and requires sacrificing efficiency. Alos, I do not believe that comparable sound quality cannot be achieved using a sufficiently high crossover point with gentle first order high pass filter for the tweeter. If fact, I have built several experimental loudspeaker drivers and complete loudspeakers using the Walsh inverted cone alignment. My single driver designs were very difficult and time consuming in construction and refinement of the cone/magnet assembly. And yes, thay sounded wonderful. But, I then decided to build some loudspeakers using the modern approach with conventional woofers turned upside down crossed over to a supertweeter. The key here was figuring out how to modify the woofer cone to behave like a bending wave converter. I ultimately came up with a modification that is easily applied, reproducible and consistent. When the modified woofer is run full range (straight line in) and is crossed over to a 1" soft dome tweeter of premium by not overly-expensive top shelf quality (chosen for it's very low Fs=800 Hz, 100W RMS) crossed over in a first order 6 dB/octave slope at 8 KHz (so that the tweeter is hardly taxed under any reasonable listening levels). the result has been a loudspeaker of surpassing fidelity. These loudspeakers are just beautiful sounding, having all the best qualities of an omni. And yes, the midrange detail is Quad-like, electrostat, clean. The key is the monopole tweeter - the controlled directivity above 10 kHz is superior to a full omni radiation. All who have heard these speakers are awe-struck. What is really amazing is how inexpensive and easy they are to built: woofer (with hand-applied mods), tweeter, one good quality polypropylene cap, solid core copper wiring throughout, and the cabinets (I used cardboard tubes) - that's all there is per speaker. One of these days, I should drawn up the plans and post them on line.