Ohm Walsh speakers; Anyone have any experience


I have been interested in the Ohm Walsh drivers, and their uniformly positive reviews, and omnidirectional nature. Does anyone have enough exposure to these to provide a critical assessment? Happy listening, D
dmason

Showing 8 responses by sean

The Ohm "Walsh Series" do not use a "real" Walsh driver, nor are they omni-directional. This series of products are basically living off of past reputation and bear little resemblance to previous Ohm designs ( A, F, G ) that did use authentic Walsh radiators. This is not to say that you won't like what they do for you with your system in your room, only that one should read their literature and claims VERY carefully. Others obviously do like them, so you may be part of that crowd. The fact that they offer something like a 90 or 120 day in-home trial ( minus shipping charges ) is quite outstanding coming from any loudspeaker manufacturer. Sean
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Zorpman: As you may be aware, i have two sets of Ohm F's. Not to side-track this thread, but i'd love to compare notes with you regarding your installation / experiences with the F's. We can do this publicly on this forum so that others can read our notes and possibly contribute to or learn from our experiences or talk privately via email. Personally, i would prefer to do it publicly as i think it provides a greater amount of resources for those interested in these rare and relatively "odd-ball" speakers or other designs that share similar attributes.

Other than that, i was going to post a link to a website that was dedicated to Walsh driver based speaker systems, but it appears that the web address is no longer valid. It was interesting if for no other reason than to see a pair of A's and F's. Sean
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Zorpman: My experience with the F's is that they have tremendous bottom end. Then again, they have a huge radiating surface area that is equivalent to multiple woofers. In a direct comparison to the mains that i'm using in my HT system ( two 12's per sealed cabinet, 4+ cu ft box with a Q of .5 ), the F's have both more bass and greater extension. While the bass of the F's is not as tight or as well defined, it is very apparent that they are capable of prodigious bottom end. The fact that i can input a digital 5 ( five ) Hz signal into them and the house shakes as the Walsh drivers flail about tells me that i'm not imagining things. If one were not worried about achieving levels over about 92 - 94 dB's at a distance of 8 - 10 feet, these would make excellent subwoofers.

Having said that, my guess is that your cabinets are not properly stuffed, your amplifiers are not capable of driving the load even though you think they should ( not uncommon ) or a combination of the two.

Many "well respected" amps that are supposedly "bass hounds" have sounded more like "whining pups" when trying to drive the low sensitivy ( Julian Hirsch measured them at 82 dB's and that's about what i get too ), low impedance ( 1.2 - 3 ohms ), high mass Walsh drivers. Any type of bridged amp need not apply as it will be trying to load into what is effectively less than 1 ohm ( as a bridged amp sees it ) at very low frequencies and 1 - 1.5 ohms across the majority of the band. This is because the nominal impedance of this speaker is more like 2 - 3 ohms rather than the "nominal 4 ohms" that Ohm advertised.

As such, one must take into account that not only must the amp be able to deal with such a load, it has to sound good doing it. Most amps that sound "good" with slightly higher sensitivity speakers of slightly higher impedance tend to fall flat on their faces with the low sensitivity / low impedance Ohm's. As such, many of the "problems" associated with how the Ohm's "sound" was not with the speakers, but with the poor / unsuitable level of amplification driving them. I've read several comments about the amps ( and even receivers !!! ) that people are driving the F's with and know for a fact that they could NEVER work well with them even though these folks think that they sound marvelous together.

As far as the cabinet goes, Ohm was less than consistent in this area and used different types and quantities of damping material inside the cabinets. By varying the density and material used, you can fine tune your bass extension and amount of damping at resonance. Out of the two pairs that i have, both sets had different quantities and types of materials in the box.

Something else that might be a hindrance to your low frequency output is the fact that the drivers were refoamed. I had my first set refoamed by a "pro" and they worked great. I had my second set refoamed by a different "pro" and he just about ruined them. NO bass output compared to the first set, etc... Ended up taking them back to the guy that did my first set and he corrected the problem by installing a different type of foam. This in turn changed the suspension of the driver, altering both the electrical and acoustical properties of the drivers.

Dmason: The newer "Walsh Series" uses a standard woofer mounted on top of a box or cylinder firing down into the enclosure. The sound that you hear is the sound "leaking" out of the vent holes in the basket of the woofer. As such, direct radiation is very low, giving the sound very diffuse and spacious properties. The sound being generated out of the front of the woofer,which is facing down into the enclosure, is vented through a port out of the box to enhance low frequency output and sensitivity. In order to minimize cancellation from nearfield reflections and increase the versatility of speaker placement, the rear section of the "mesh can" has acoustic damping / blocking material in it. This helps to both direct the sound out front while blocking radiation to the wall situated behind the speaker.

The top end is handled by a tweeter that fires towards the front and is mounted on the basket of the woofer. All of the crossover components are also mounted to the basket of the woofer. I might add that the construction of this whole assembly is NOT very pretty and that's why they try to "seal" the cans. They don't want you going in these "factory sealed units" because once you do, you'll find out that there is no "Walsh driver" in there and what a mess you paid good money for.

As you can see, the sound is not omni-directional, it uses nothing special ( standard drivers in a non-standard mounting array ) and the sound and presentation is nothing like that of a well set up pair of A's or F's. Then again, falling short of a well set up pair of Ohm's is nothing new. There aren't many speakers that are capable of producing a 360* radiation angle out of a point source phase coherent full range driver. Sean
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For a short time, you'll probably be able to see the inside of a set of Walsh 5's as they have a pair partially pulled apart on Ebay. I will only say that these look a LOT neater and better put together than the set of Walsh series that i previously saw. Sean
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I would love to be able to listen to the German Physiks Walsh "Bending Wave Transducer" ( Dick's Dipole Driver or DDD as they call it ). I am curious as to if the driver uses some type of internal damping material inside the driver to damp the titanium from ringing. So long as they covered that aspect of performance, my thoughts are that the bass would probably not be up to the task given the design that they are using. Sean
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Zorpman: I don't doubt that the Dynaco's are stable driving the load. Quite honestly, while the Dynaco's may be up to the task in terms of brute force, i'm certain that there is plenty of room to move in terms of improved sonics. I'd be curious as to what amps, if any, that you've tried on the F's other than the Dynaco's and the results that you've obtained.

Also, are you using the factory speaker cable at the base of the speaker or are you directly connecting to the binding posts at the driver ? If you are running the internal factory wiring, you are in for a REAL treat once you bypass it.

As far as the foam surround goes, it may still be quite healthy and in "perfect shape". That does not mean that it is the appropriate "stiffness" or that the driver is properly aligned. In severe cases, you may even be running into the driver binding up, resulting in limited excursion and a lack of deep bass. That is EXACTLY what i ran into on my second set of F's after a "world famous" speaker repair facility claimed to have repaired them. I then had to pay someone else to remove the fresh glue & foam and re-do the whole job. Evidently, the first shop knew that they must have screwed up as they refunded the entire amount.

My biggest problem with all of this was that these speakers spent well over a year in "limbo" due to all of these problems. Obviously, not all speaker repair facilities are up to refoaming these drivers, so be VERY careful with whom you trust the wellfare of your "babies" to. Sean
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Here are a few websites that discuss the Ohm A's, F's and later "Walsh series" of Ohm brand speakers. As a side note, i've included a link that discusses modified Hill Plasmatronics. Since Plasma drivers are "mass-less" and radiate in what is basically an omni-directional pattern, they are theoretically the most accurate transducer available. Only problem is that they aren't capable of high spl's, have phenomenally limited low frequency response, produce harmful emissions of ozone and are generators of mass levels of RFI ( in most cases ). As such, there are drawbacks involved : )

Brief overview of Walsh design from Singapore. This one kind of combines info on the original Walsh drivers with the later "Walsh series" type drivers that i commented on above.

Ohm A, F & Walsh series written about as being "unique speakers". Also includes comments about "skinny speakers" : )

Modified Plasmatronics, comparisons of Ohm A cone vs Ohm F cone Let's just say that the results obtained with the modified Plasmatronics make ANY other speaker known to mankind look "really bad"... The owner of the Hills that runs this website sold his Ohm A's after getting the Plasma's to do what he wanted out of them.

There was a Walsh driver based website on AOL that is no longer running, but it may have been moved and i simply haven't found it yet. I do know how to contact the person that ran the site and am working on finding out the current address, if still up and running. Sean
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Huff came to the CAS last year and did a demo with his gear. Needless to say, i was thrilled at the chance to both hear and see these speakers in action. Unfortunately, he did not bring the DDD based system but instead brought some speakers of relatively conventional design. They weren't bad or anything but it was a major let-down to say the least. Sean
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