Ohm F’s by Millersound

Jeremy64

Active Member
9A19A79F-6DF6-4269-B245-EC42B11ABDE4.jpeg 48848ED7-22B0-43E0-B4F7-67CD2A992700.jpeg F81A299B-7757-4B60-B6CF-A80D505E4DBE.jpeg 4BA1BB7C-C77B-40A4-A506-E1758EA3A60C.jpeg I just got back from Lansdale, PA where Bill from Millersound reworked my old Ohm F’s. A month ago I provided a pair of non working, dry rotted, but unmolested pair of Ohm F drivers. He completely rebuilt them to much better than new condition. I can’t even explain how awesome they look and sound. Here’s some pics.
 
Last edited:
I wish somebody could explain what it is that Bill from Millersound does to improve the performance of the Ohm F's. I've heard he doesn't refurbish them often anymore and doesn't like them shipped to and back because of damage risk. As a result I'll probably never have a chance to get mine upgraded and wish I had a few hints about the improvements.
 
I wish somebody could explain what it is that Bill from Millersound does to improve the performance of the Ohm F's. I've heard he doesn't refurbish them often anymore and doesn't like them shipped to and back because of damage risk. As a result I'll probably never have a chance to get mine upgraded and wish I had a few hints about the improvements.

Here’s what I know. You are correct, he only does 3 F’s pairs a year because the number of hours it takes him. He’s a massive fan of the speakers. Yes again on the shipping. I drove them down and picked them up (6 hours each way). Shipping these drivers would be a nightmare I wouldn’t trust and shipper with such a rare driver. As for what is actually done, I’ll get some more details. I do know he only reuses the cone and frame. The rest is updated. From observation, he replaces the spider, the wiring, the fuses, the surrounds and the ribbon tweeter and dampens the metal frame. Afterwards they are 6 ohm speakers and can be easily be driven by as little as 45 watts (what I’m currently using). I’ll take more detailed pics if you’d like.
 
Here’s what I know. You are correct, he only does 3 F’s pairs a year because the number of hours it takes him. He’s a massive fan of the speakers. Yes again on the shipping. I drove them down and picked them up (6 hours each way). Shipping these drivers would be a nightmare I wouldn’t trust and shipper with such a rare driver. As for what is actually done, I’ll get some more details. I do know he only reuses the cone and frame. The rest is updated. From observation, he replaces the spider, the wiring, the fuses, the surrounds and the ribbon tweeter and dampens the metal frame. Afterwards they are 6 ohm speakers and can be easily be driven by as little as 45 watts (what I’m currently using). I’ll take more detailed pics if you’d like.
 

Attachments

  • EEB44231-4AD3-4BB4-9B92-D99895A22647.jpeg
    EEB44231-4AD3-4BB4-9B92-D99895A22647.jpeg
    26 KB · Views: 90
  • F6339EE2-F9C7-42F5-BC06-6469B674B43A.jpeg
    F6339EE2-F9C7-42F5-BC06-6469B674B43A.jpeg
    76.3 KB · Views: 95
  • CB025E24-BAAB-485E-B341-844CF57C98A3.jpeg
    CB025E24-BAAB-485E-B341-844CF57C98A3.jpeg
    38.7 KB · Views: 92
  • DD660D9C-BA0D-4B2A-8B68-3A13EF07CA40.jpeg
    DD660D9C-BA0D-4B2A-8B68-3A13EF07CA40.jpeg
    69.3 KB · Views: 89
I'm sure the real blessing is in the hearing -
but getting them to run with just 45 watts seems like a real advantage!
 
Beautiful !!!! I'd love to hear a pair of those some day. I have a set of their SSC-4900's on order, I hope to have them by the end of the month :)
 
I'm sure the real blessing is in the hearing -
but getting them to run with just 45 watts seems like a real advantage!

Prior to the restore the proper wattage for these seemed only to be folklore and internet opinions.
 
I'm sure the real blessing is in the hearing -
but getting them to run with just 45 watts seems like a real advantage!

Yes, this would be a big benefit.

Prior to the restore the proper wattage for these seemed only to be folklore and internet opinions.

And that folklore/internet opinions are from when they were new. The common quote is that it took 200 watts for the Ohm F to sound good and 201 watts to blow it up.

If one can get good sound with 45 watts and not blow it up until 201 watts there is a lot more listening room in that wattage than the original power requirements.
 
Yes, this would be a big benefit.



And that folklore/internet opinions are from when they were new. The common quote is that it took 200 watts for the Ohm F to sound good and 201 watts to blow it up.

If one can get good sound with 45 watts and not blow it up until 201 watts there is a lot more listening room in that wattage than the original power requirements.

I’m using a Marantz 2245 now and it sounds incredible. When I picked the speakers up Bill demo’d then with a 65 watt unit and they rocked even without the cabinets. I’m most likely going to end up in the 70/80 watt range. I have an SAE 2500 sitting around, but it’s just too much. I did try it with a 20watt tube amp and not enough.
 
NEVER TOO MUCH POWER.....You are in control of the throttle i.e. volume knob.. More power will help control LF better....and please move that cassette deck off that poor 2245.. That sucker has little to no ventilation the way it sits....
 
Very nice pix Jeremy. So does he actually change the magnet assembly ? I guess that would explain the increase in sensitivity that you describe. I gather that a stiffer spider is used since they all suffer from sag after so many years and a relatively heavy cone. Does that mean the deeper bass is reduced compared to the original design ?

Sorry for all of the questions. I literally never get any opportunity to discuss ohm f behavior with anyone.
 
He only does 3 sets a year?? Man, this came to mind -

maxresdefault.jpg
 
Very nice pix Jeremy. So does he actually change the magnet assembly ? I guess that would explain the increase in sensitivity that you describe. I gather that a stiffer spider is used since they all suffer from sag after so many years and a relatively heavy cone. Does that mean the deeper bass is reduced compared to the original design ?

Sorry for all of the questions. I literally never get any opportunity to discuss ohm f behavior with anyone.

I never got to hear the F’s before the restore but the bass is very deep. I was also told to remove some of the dampening material within the cabinets. I havent done that yet but will report back with pic and progress
 
Very nice! Can't go wrong with a nice professional restoration by a true professional. I would also be very interested to know what all is done as part of the restore, as I spent a good deal of time, effort and research restoring my own set. I posted a thread about it here: http://www.audiokarma.org/forums/in...-set-of-legendary-ohm-f.780113/#post-10715774

I'm most interested in what was done inside the cone. Most people neglect that part. From the factory, Ohm glued open cell foam cut into trapezoids on the aluminum section, and stuck titanium dioxide rope caulk (Mortite) behind the titanium section. Most unrestored specimens would show crumbling foam and missing Mortite (it would dry out and fall off) by now. Would you mind taking a picture of inside the driver to show what Bill did? I'd owe you one.

Also, what do you mean when you say he "replaced the ribbon tweeter"? Model Fs don't really have a tweeter. It's all just one cone. The titanium upper section serves to generate the high frequencies.

I will back you up in your claim that properly functioning sets don't need gobs of power, making the old wive's tale completely untrue. Mine run very well on a 2 pound, 50 wpc TPA 3116 chip amp. But I've attributed it's success to the damping factor provided by the class D amp. Damping is important to the Fs as it works to control that heavy cone. Like you, I also tried a tube amp that had no problem handling big Polk SDA SRS, but failed miserably with the Fs, due to low damping. You could actually see the cone floating around uncontrolled. But I have to say I'm actually a little surprised yours run so well on a Marantz 2245. I've always considered those a little wimpy, comparatively. But hey, if it works, it works!
 
Back
Top Bottom