Ohm Acoustics Model I

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As you may have seen in Dollars & Sense, I just bought a pair of Ohm I's.
So far everything seems good except that there is no sound from one of the low (larger) tweeters.
I pulled the tweeter and removed the perforated cover. There is no continuity thru the voice coil even when measured right where the flexible wires enter thru the dome.

After S/H, Ohm wants nearly as much to exchange one low tweeter as I paid for the whole pair of speakers.
Considering how nice they seem to be, I will probably go ahead and buck-up for that if I can't find a used one somewhere. I already posted a WTB in Barter Town...

I was amazed by the size and weight of the low tweeter magnet. MUCH larger than what I am used to, being an EPI guy. The crossover is also ridiculously complex, compared to the single 10uF cap used in most EPI's.
(As an EE, I imagine all of the complex phase relationships that must be at work in the Ohm crossover, and find it hard to believe that it doesn't result in a mish-mash of un-natural sound.) I would be curious to see the crossover schematic if anyone has it...

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I feel your pain, I am in need of a Pair of the low tweeters. Although I appreciate Ohm supporting their discontinued products, for the price of a pair of these tweeters, I could have a nice used set of B&W's. So far, I just haven't been able to bring myself to part with that kind of coin.
 
I upgraded the woofers for a pair of C2's, from Ohm. I found the cost on par with comperable PE woofers. Your I's should sound nice.
I see comparison to cost of used speakers a reflection of low market values of used speakers in general. With exception of few prized brands and models.
Not affiliated with either company.
 
Here are a few pictures of what I found on my bad low tweeter.
The break was where the VC wire attached to the bottom corner of the lower solder pad, down in the ferrofluid, not visible in the first picture.
I bent the loose end of the wire up to make the break obvious in the close-up.
I think the only chance to fix this would have been to unsolder the green wires from the flex wires and slide a single edge razor blade under the black plastic ring to loosen it from the metal and lift the whole VC, cap, surround, and black ring in one piece. Not easy to do without damaging it.

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ouimetnick said:
Not sure why they even want the old tweeters back. See my thread. http://audiokarma.org/forums/index.php?threads/what-tweeter-is-this.777268/ They just replace them with Wavecor units.
Click to expand...

They told me that they are collecting the faceplates for use in a future version of the tweeter that they are working on, and that I didn't need to send them the whole tweeter, just the faceplate.
How do the Wavecor units sound compared to the originals? They look tiny compared to the originals.
How do they mount? Did they supply faceplates not shown in your pictures?
 
I also sent them my old face plates. Not sure how they compare since both of my old tweeters also tested open. They made new face plates out of some very thin plywood and used a thick piece of plywood to help support the tweeter. Also, they charge $80 for a high tweeter upgrade... No need to spend that much. Nothing custom, it's just a Dayton Audio ND20FB-4 with a self resetting PTC fuse and a lightbulb limiter (paralleled) in series with the positive terminal.
 

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I could use an answer myself about a set of OhmLs that I traded for a set of EPIm-201s. Now before you go and say that the EPIs were hands down better I don't think so for the logistics in my room. We both listed them equally on C/L and I proposed the trade for 1 I
 
Sorry guys my machine messed up and I'll try again. I had a set of EPI m-201s, my 3rd set of EPI speakers. The trader had a set of Ohm model L and I proposed a trade because the EPIs were just to big for my room and wanted something else for exchange. He brings them over and we compare sound and cosmetics and the Ohms were excellent (including grill covers) and the M- 201s were fair/good but he said he could fix the grills and had 1 Radio Shack drop in which he knew but had an 8'' spare. I was blown away by the sonics of this larger bookie compared to the EPI sound of which I already was used to plus the fit in the room. My only concern and I called Ohm in BKLYN was that there was no logo on the dust cover of the Ohm driver. Evan said from what he could tell from the pic that this was an Ohm speaker not a drop in but would not send a stencil out to me because they wanted to test the speaker and then lay down a logo for $90 and IIMG_4395[2].jpg IMG_4396[2].jpg said kishmeirintuchas but politely. If I had the room the EPIs were living room presentable but I wanted the Ohms and now are on metal slant stands and push around clean sound that surprised me a lot. I see no down side to Ohm L if you get the ones for the room they sit in. I think the L is the totl for Ohm cabinet style speakers then on to the Walsh series. The sheen on the right hand speaker is just a damp wipe down that did not evaporate before I took the pic......Lew
 
Well, I got the replacement low tweeter from Ohm a few days ago. It was just as ouimetnick posted, mounted to a front plate and perf dome to look like the original from the outside. It weighs about a tenth as much as the original, but sounds similar as far as I can tell.

I set these up in my demo room which is presently powered by a Pioneer SX-1050 receiver. I have them side-by-side with my EPI 350's.
At low to moderate volumes the EPIs sound a lot better than the I's. The I's go deeper, but have a deep hole in the midrange at these volumes.
Cranked up close to 12 o'clock on the 1050 the I's really come alive and sound MUCH better. Wow! Even better than the 350's. Very natural sounding while shaking the house. Too bad they don't sound that good at normal volumes.
I'm leaving the 1050 in place for now, as I have a buyer lined up, but as soon as it's gone I will try these with my SPEC 1-4 combo, or my SAE Mk IIIC.
Hopefully the ballsier amps will wake the I's up at lower volumes.
 
Same experience here and then some. I originally tried mine with my Hafler XL-600. Bass was there, but they sounded unusually bright with poor mids. Tried it with my DH-120 (60 watt per channel) and they sound much better. I’m not using them right now due to how large they are and my folks don’t want them where I feel they sound their best, so until I clean out a spot for them, they have to wait.

I’m still not used to the omni directional sound they offer and when I called Ohm, I asked how I can get these to image like a set of Ohm C2s. I was told that I’ll never get the precise imaging with them, but should be able to get something. It is cool how the sound remains the same all around the room rather than a sweet spot like the C2 or any conventional speaker. I do like how deep they go, no need for an extra subwoofer.
 
AFP1 said:
I feel your pain, I am in need of a Pair of the low tweeters. Although I appreciate Ohm supporting their discontinued products, for the price of a pair of these tweeters, I could have a nice used set of B&W's. So far, I just haven't been able to bring myself to part with that kind of coin.
Click to expand...
Did you ever get a pair of low tweeters?
 
ouimetnick said:
I also sent them my old face plates. Not sure how they compare since both of my old tweeters also tested open. They made new face plates out of some very thin plywood and used a thick piece of plywood to help support the tweeter. Also, they charge $80 for a high tweeter upgrade... No need to spend that much. Nothing custom, it's just a Dayton Audio ND20FB-4 with a self resetting PTC fuse and a lightbulb limiter (paralleled) in series with the positive terminal.
Click to expand...

That's what they sent you?! I have a bad low tweeter, I think I'm going to replace them both with these - https://www.parts-express.com/peerless-by-tymphany-bc25tg35-04-1-fabric-dome-tweeter-4-ohm--264-1444, and keep the faceplates. May have to do some monor surgery on the tweeters to get the mounting holes to line up, but these are relatively inexpensive and won't go broke if they don't work out. The bad tweeter reads about 3.3 ohms but no sound. I think it suffered some water damage and is seized up.
 
dzkfraser said:
That's what they sent you?! I have a bad low tweeter, I think I'm going to replace them both with these - https://www.parts-express.com/peerless-by-tymphany-bc25tg35-04-1-fabric-dome-tweeter-4-ohm--264-1444, and keep the faceplates. May have to do some monor surgery on the tweeters to get the mounting holes to line up, but these are relatively inexpensive and won't go broke if they don't work out. The bad tweeter reads about 3.3 ohms but no sound. I think it suffered some water damage and is seized up.
Click to expand...

Scratch that PE says the manufacturer only sells those in lots of 1000 - figgers
 
dzkfraser said:
Scratch that PE says the manufacturer only sells those in lots of 1000 - figgers
Click to expand...

Since I couldn't get the peerless, I went with these - https://www.parts-express.com/dayto...nce-series-fabric-dome-tweeter-4-ohm--275-141

I kept the ohm faceplate bit had to drill holes in the daytons faceplate to mount them as the mounting bolt circle was slightly smaller - I also kept the ohm mesh grill. Got them hooked up and they sound good. Not sure what i'll do with the ohms, since one of them is bad
 
^^^They are a shell of a company that once sold a great speaker....I would never allow them to downgrade my original Ohm F's or I's with modern inferior drivers......
 
leftfielder said:
Sorry guys my machine messed up and I'll try again. I had a set of EPI m-201s, my 3rd set of EPI speakers. The trader had a set of Ohm model L and I proposed a trade because the EPIs were just to big for my room and wanted something else for exchange. He brings them over and we compare sound and cosmetics and the Ohms were excellent (including grill covers) and the M- 201s were fair/good but he said he could fix the grills and had 1 Radio Shack drop in which he knew but had an 8'' spare. I was blown away by the sonics of this larger bookie compared to the EPI sound of which I already was used to plus the fit in the room. My only concern and I called Ohm in BKLYN was that there was no logo on the dust cover of the Ohm driver. Evan said from what he could tell from the pic that this was an Ohm speaker not a drop in but would not send a stencil out to me because they wanted to test the speaker and then lay down a logo for $90 and IView attachment 1017211 View attachment 1017216 said kishmeirintuchas but politely. If I had the room the EPIs were living room presentable but I wanted the Ohms and now are on metal slant stands and push around clean sound that surprised me a lot. I see no down side to Ohm L if you get the ones for the room they sit in. I think the L is the totl for Ohm cabinet style speakers then on to the Walsh series. The sheen on the right hand speaker is just a damp wipe down that did not evaporate before I took the pic......Lew
Click to expand...

I need two new metal cages for some large ohm walsh drivers as one was quite crushed when I received them and the other was missing. Called Ohm and John said they were indeed available but I would have to send both walsh drivers in to the factory for testing and when all required parts were changed then they would attach the new metal grill tops and charge me accordingly. I wish I had been aware of the word "kishmeirintuchas". I know what a tuchas is and surmised the rest. While I understand John wanting to evaluate the performance of the drivers for quality control, the damage that would probably result in shipping such large, unprotected walsh woofers with the cages missing scares me. The crossovers and tweeters glued and soldered on the woofer magnet assemblies are so fragile when not covered by the protective cages I hate to risk shipping again.

Anyhow, I know I've seen that perforated metal used in walsh cages/grill tops numerous times through the years, possibly as decorative metal covers for hot water radiators or for ornate vent covers on hvac vents . They even use similar but heavier perforated metal for Walmart's courtesy benches throughout their stores. It's basically sheet metal perforated with holes to allow air passage.. (or sound passage) Does anybody know what the perforated metal sheeting is called and/or where it might be available?
 
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