jimbecky48001
Active Member
I was watching those also.
Ohm F questions?
- Thread starter mgfred
- Start date
mgfred said:
Welcome fellow lover of great sounds! Hope you enjoy the magnitude of information contained within these forums.
In response to your questions.. Here's what I would do.. Order a couple 12" foam surround rings off ebay.. get a can of spray adhesive or rubber cement.. turn on some tunes.. clear an area where you can get a little messy and dive into those beasts.. You'll have about $20 and an afternoon at stake. It'll take you a couple hours per driver.. maybe chill down some late harvest Riesling and enjoy it...
Here goes:
Remove the driver from the base with (2) wing nuts.
Remove any foam remnants on the cone bottom.
Mark the Driver and sub base alignment to make later assembly easier.
Flip the driver upside down onto it's motor assembly.. remove the 4 nuts and bolts securing the driver to the wood sub base. remove the sub base and cloth (it's just stretched over the frame by the wood..
You can now remove any foam /dirt/dust that has gotten into the cone assembly..
You are about ready to start re-foaming... )
Do a dry fit of the foam surround.. get a feel for what is going to happen. I think it best to put the curve of the foam down (when upright) or up when flipped over. You should need to snip the ID of the surrounds (I have found a 3/8" snip every 1/2" to 3/4" works) to get them to conform to the ID of the driver.. The foam surrounds I have used are about 11 5/8" OD and 8 1/4" ID when laying flat.
This part is a little intimidating.. but remember if your foam job doesn't come out right.. you can always pull the foam off and
1. Try again with another piece of foam
2. Take it to the pro shop
3. Trade them in to Ohm Acoustics
4. Scrap them
All of the above, BTW, are the same as your current options...
After trimming up the foam.. spread some rubber cement and start having fun.. I find it easier to have some music playing in the driver as I am doing this.. BTW.. not loud just comfortable listening.. I would glue the foam to the inside of the cone first. start by applying in sections of 1/8 of the circumference.. and build on it.. after I have done a few I can work on about a 1/2 of the cone at a time. Then I find it easier to glue the foam to THE ID (not the flat) of the frame.
Play with it, take your time and the driver should come out sounding like new.
Regarding the info on Ohms' web site, I believe Ohm just wants to sell you some more $ 4,000 speakers...
Now, regarding driving these things.. In all my years with these things and the number of systems I have hooked them to.. I find it hard to believe that anyone could blow an amp or blow a driver by using them.. However, you have a very expensive piece there.. How about spending the couple hundred dollars you saved re-foaming them yourself and go on ebay and pick up a used SAE 2400, 2500 or 2600 power amp.. hook it up to the pre/outs on the reciever and drive them with that?
If you pull this all off, You'll like the sound.. I do :thmbsp:
Sorry it took me so long to get back to you..
jimbecky48001
Active Member
There is also foam between the different materials that make up the cones that will need replacing and alignment is very important with the f's.
jimbecky48001 said:
There is a foam wrap inside the cone. I have never replaced it on any of the cones I have done. perhaps some are deteriorated further than those I have seen.. I couldn't even comment on what it would take to replace it.. Maybe you can Jimbecky? I would be interested..
Yes, as with any speaker, alignment is important, but I haven't had any problem with that given the length of the cone and the angle of the dangle....
I have had to add in some extra "lift" to the spiders in some cases..
I've successfully refoamed Ohm F drivers. Tested a refoamed one vs. an original... nobody could tell any audible difference, in a quick test.
I've "stablized" the foam inside the cone, with a very fine mist of spray adhesive. Seems to get into the foam, and prevent it from flaking off, while maintaining the acoustic properties. And since it's inside the speaker, there's no problem with it being "sticky" or anything like that.
As for the spiders- I've corrected sag, in two ways: 1) Preload the foam, just a tiny bit lower on the cone, so the foam lifts the cone just a bit (about 1 mm or so). and 2) take a heat gun or hair dryer, place the speaker upside down (where the weight of the cone is pushing BACK on the spider), and gently and EVENLY heat the spider with the heat gun. This will cause the spider to "reset", akin to pressing a shirt (after all, a spider is nothing more than a type of "starched" fabric, in essence). You will want to do the heating thing AFTER it's refoamed and aligned correctly, as to maintain alignment.
I've done these Ohm Walsh driver refoam jobs; so far, after doing about a dozen of them, I've had a 100% success rate. Sure, if the driver has been cooked/burned up (and that's only usually possible, if somebody replaces the fuse with an improperly high value) it can't be done, but of the Ohm drivers I've personally seen, they've all been in good enough condition to refurbish.
Aas for pricing- I can understand why someone would charge more than a normal driver, since these require lots of care and time. Last pair I did, I charged around $80.00 each... which I think is a fair price.
Regards,
Gordon.
I've "stablized" the foam inside the cone, with a very fine mist of spray adhesive. Seems to get into the foam, and prevent it from flaking off, while maintaining the acoustic properties. And since it's inside the speaker, there's no problem with it being "sticky" or anything like that.
As for the spiders- I've corrected sag, in two ways: 1) Preload the foam, just a tiny bit lower on the cone, so the foam lifts the cone just a bit (about 1 mm or so). and 2) take a heat gun or hair dryer, place the speaker upside down (where the weight of the cone is pushing BACK on the spider), and gently and EVENLY heat the spider with the heat gun. This will cause the spider to "reset", akin to pressing a shirt (after all, a spider is nothing more than a type of "starched" fabric, in essence). You will want to do the heating thing AFTER it's refoamed and aligned correctly, as to maintain alignment.
I've done these Ohm Walsh driver refoam jobs; so far, after doing about a dozen of them, I've had a 100% success rate. Sure, if the driver has been cooked/burned up (and that's only usually possible, if somebody replaces the fuse with an improperly high value) it can't be done, but of the Ohm drivers I've personally seen, they've all been in good enough condition to refurbish.
Aas for pricing- I can understand why someone would charge more than a normal driver, since these require lots of care and time. Last pair I did, I charged around $80.00 each... which I think is a fair price.
Regards,
Gordon.
mgfred
"Danger Seeker"
GordonW said:
The local guy quoted me $250 for the pair, considering how much it would cost to pack and ship these drivers, I don't think I could do better.
Me doing the job myself is really out of the question. While I may solve software problems for my customers and do my own board swapping on computers, this type of repair is not one of my talents.
Repairing these guys would give me a quick fix that I could use the speakers fairly soon. Upgrading them is something I'd have to wait a few months on since I have to remodel the bathroom in the master suite of the house this spring. I'd have to go the way of a seperate amp I guess if I want to run these as true Fs..
Thanks for all the input guys!
Cosmos:
I have talked to a guy at the AVSForum that actually has a set of Ohm As. The user manual that came with the Fs (in pristine condition) is from 1973 and covers both the A & F models. Good luck in finding them!
Fred
mgfred
"Danger Seeker"
I think I'm going to see if the Fs can be saved and have my local speaker guy take a look at them.
Instead of using them in my "great room" HT, I can put them in the den. That may make things easier since all 500+ of my LPs are in there anyway in bookcases.
If it's a go on the Fs, my quest will be for something to power them with. Let's see what the speaker guy says after he looks at them.....
Instead of using them in my "great room" HT, I can put them in the den. That may make things easier since all 500+ of my LPs are in there anyway in bookcases.
If it's a go on the Fs, my quest will be for something to power them with. Let's see what the speaker guy says after he looks at them.....
mgfred
"Danger Seeker"
Been listening to them for about a hour now. All I can say is incredible........
I may have made a mistake putting them in my den. They overpower the hell out of it.
So far I've warmed them out with some horns for Chicago "Anybody know what time it is?", sax from the "Pink Panther Theme", heavy guitar playing Ted Nugent's "Together", then to some old 70's fun with Jefferson Starship's "Miracles" and some very under-rated Jethro Tull "Too old to rock'n roll".
Now I'm giving the bass a workout with Bowie on "Cat People" and going through all of "Ziggy Stardust". Incredible the bass these put out..... put's my JBL sub to shame.
Over the last couple of weeks I picked up a NAD C272 amp along with a NAD 701 receiver to use as a preamp. The Fs are so loud I don't have to push them at all to may them shine. Yes, I said the Fs are loud! It may have to do with my 12x12 den I have them in, but I can walk all over the house through the halls, upstairs, nowhere am I safe from these...
I'm glad I had them refoamed, the last couple of hours have been an breathtaking listening experience!
I bought a pair of Ohm C2s on Ebay last week just in case the den couldn't handle the Fs. When the C2s arrive, I'm going to set up the Fs in my "great" room and use my Elite VSX-59TXi as the preamp and set up the Fs and the C272 as a seperate zone. If I listen to these too long in my den, I'm scared my ears may start bleeding.
I may have made a mistake putting them in my den. They overpower the hell out of it.
So far I've warmed them out with some horns for Chicago "Anybody know what time it is?", sax from the "Pink Panther Theme", heavy guitar playing Ted Nugent's "Together", then to some old 70's fun with Jefferson Starship's "Miracles" and some very under-rated Jethro Tull "Too old to rock'n roll".
Now I'm giving the bass a workout with Bowie on "Cat People" and going through all of "Ziggy Stardust". Incredible the bass these put out..... put's my JBL sub to shame.
Over the last couple of weeks I picked up a NAD C272 amp along with a NAD 701 receiver to use as a preamp. The Fs are so loud I don't have to push them at all to may them shine. Yes, I said the Fs are loud! It may have to do with my 12x12 den I have them in, but I can walk all over the house through the halls, upstairs, nowhere am I safe from these...
I'm glad I had them refoamed, the last couple of hours have been an breathtaking listening experience!
I bought a pair of Ohm C2s on Ebay last week just in case the den couldn't handle the Fs. When the C2s arrive, I'm going to set up the Fs in my "great" room and use my Elite VSX-59TXi as the preamp and set up the Fs and the C272 as a seperate zone. If I listen to these too long in my den, I'm scared my ears may start bleeding.
mgfred
"Danger Seeker"
kichijai said:
Why would I want to do that?
I did try to get a "mint" set of Walsh 5s on Ebay a month ago and lost out with like 10 seconds left. That's when I found these Fs. I don't think I'm getting rid of these anytime soon!
If you know anybody selling any mints 5s I would pay $2500 for them in a heartbeat if they were in good working order.
mgfred said:
I have never heard the 5s, but I have 4's (2's and G's) and Fs. The 4 doesn't even get in the ballpark with the F. Maybe there is a huge difference between the 4s and the 5s, but there is a incredibly large difference between the 4s and the Fs. I find it hard to even compare them. they simply aren't in the same league.
I would pay to have Fs refoamed every 5 years before I would buy anything else that I know of in the Ohm line. I can't tell you there isn't better, but if there is, I haven't heard it with the possible exception of the As which I haven't heard in close to 30 years.
jimbecky48001
Active Member
I will have a new set of Walsh 4.5's set up next weekend and can report out at that time.This is the Walsh 4 cabinets with brand new Walsh 5 drivers.
mgfred said:
Perhaps. Many years ago, I had a set in a bedroom about that size. I thought they sounded good there, as I recall, but they certainly open up in a larger room. A better speaker for the den might be a Ohm G or a 2 or 4?
The fallacy of Fs is that they won't get quite loud and won't fill a big room. They will, but they will not get to 140db. Then again, I don't want to hear 140db.. and definately don't want to listen to music at that level. In fact, many good speakers simply do not get real loud.
mgfred said:I'm glad I had them refoamed, the last couple of hours have been an breathtaking listening experience!
My experience with Fs has been and I suspect yours will be:
1. That they will continue to amaze you for years to come.
2. I can't imagine myself being without at least one set.
3. You will find that you stop listening to what people say about them. You will likely say something like uh-huh when you are told how big their limitations are, and shake your head as you walk away knowing that the people telling you how big the limitations are simply don't know the greater aspects of the speaker.. how damn good they sound.
4. You will likely get a set of Boomers (you may already have them) for listening when you want it very loud, but you will listen to the Fs by far, most of the time.
mgfred said:
The C2s were a very underrated speaker in the Ohm linup. It was Ohm's L-100. It just plain rocks. We sold many of them. It was Ohms most popular speaker in the 70s.
The H was also a very under rated speaker. It was a box speaker that was very refined, yet it got pretty loud. Sort of a cross between the C2 and the F. If you ever see a pair and they are resonable.. buy them.
jimbecky48001
Active Member
Well My new Walsh 5 drivers arrived today and I have to say they are AWSOME. :thmbsp:
special thanks to hiphi.