[rajacat]

My Super Bipoles seem reproduce music very well at low volume. I suspect that this is partially true due to their high efficiency (96 db). Would using the Hemp alnico (93db) in the same cabinets hurt low volume sensitivity? I would be very interested in seeing the freq. response graphs for both the 4.5" hemp and hemp/alnico drivers.

Raja

[DRCope]

The 4.5" are really working out and they are way better than I anticipated. I have fuller bass and the transparency of the 8"s. Scale is a bit smaller than the larger speakers, but it's all there. I don't know about an alnico version of the 4.5" driver yet, but I did get the latest plot on the 8" alnico and it's really good. Very well balanced and smooth in the mids with bit more bass energy. I hope to get the drivers to test. One drawback is they are about 93dB spl.

Man, oh man, I feel a road trip coming on! While the siren call of the hemp XRS sings in my ears, I did manage to remember that the 45 tube is my drug of choice, so what's a boy to do? I'm really used to a big sound, and alnico and triodes go together like soup and sandwich - well, okay, champagne and caviar - so, crazy as it sounds, and it DOES sound crazy, bipolar alnico hemp 8's (which incarnation? I have no idea!) are very tempting. Then again, I could either give up some 'scale' or slide up the triode food chain to 2A3's. Or have Vinnie mod my Clari-T. Or get a Signature 30 . . .

So many options, so many unknown sounds . . . . Dontcha love it!   

[Louis O]

Hi Rajacat,

Using the alnico magnet will hurt sensitivity on any of the drivers. The 8" model lost about 2dB, but the graph looks very smooth and bumps in low bass.

The 4.5" is what I'm on the fence about.

Hi Dave,

Lots of options for sure and I will be happy to make some customs speakers. If the deal with the new shop goes through I will have customs made for the showroom.

I have figured out the Hemp revolution and the OBs finally out and will be getting the proto types drivers after the New Year. The drivers are going to be 16 ohm only. The OB is a 1.5 way in parallel and will end up as 8 ohm.

Thanks again,
Louis

[jrebman]

I have figured out the Hemp revolution and the OBs finally out and will be getting the proto types drivers after the New Year. The drivers are going to be 16 ohm only. The OB is a 1.5 way in parallel and will end up as 8 ohm.

Louis,

Do you or Vinnie have any predictions as to how the Signature RWA amps are going to deal with a 16-ohm load?  Are those of us with B-200 based speakers going to need to look into autoformers for our amps that don't have 16 ohm drive capability?

Thanks,

Jim

[Vinnie R.]

I have figured out the Hemp revolution and the OBs finally out and will be getting the proto types drivers after the New Year. The drivers are going to be 16 ohm only. The OB is a 1.5 way in parallel and will end up as 8 ohm.

Louis,

Do you or Vinnie have any predictions as to how the Signature RWA amps are going to deal with a 16-ohm load?  Are those of us with B-200 based speakers going to need to look into autoformers for our amps that don't have 16 ohm drive capability?

Thanks,

Jim

Hi Jim,

Sorry I missed this one.

The RWA Signature amps will have no problem with a 16-ohm load.  However, the max output power into such a load will be approx reduced in half.  No a big deal with a high efficiency driver.  Most likely, you'll need to turn up the volume a little more to get the same sound level out of it.  Of course if the driver is more efficient than the B200, that would counter this need somewhat. 

Once Louis gets the new high Qts 8" hemp driver, I plan to borrow it and run it on my OBs and listen to it and swap with the B200 and listen to their sonic character.

I believe Louis wants to use 16-ohm because for his upcoming OB speaker, he'll be using two of these 8" drivers in parallel to make it an 8-ohm speaker (I guess more "tube friendly" than a 4-ohm speaker).  The bottom driver will be in a sealed aperiodic box and will only be for handling lower frequencies, which is needed to combat the natural OB rolloff of 6dB/octave. This bottom driver will use a simple 1st order filter (an inductor), with a 6dB/octave rolloff going the other way.  This is the latest I heard from Louis, that is. 
New Omega OBs with matching OEM Tone Tubbey Hemp drivers....I can't wait to hear it!!!      And I can't wait to hear the new "HEMP Revolutions!"

Best regards,

Vinnie

[jrebman]

The RWA Signature amps will have no problem with a 16-ohm load.  However, the max output power into such a load will be approx reduced in half.  No a big deal with a high efficiency driver.  Most likely, you'll need to turn up the volume a little more to get the same sound level out of it.  Of course if the driver is more efficient than the B200, that would counter this need somewhat. 

Thanks, Vinnie, I wasn't really sure how much the power would fall off at the higher impedance -- i.e. didn't know if it was a linear relationship or not.

I'm still breaking the Revolutions in, and the bass is filling out some, but I haven't completely ruled out the possibility of a BSC for this yet.  It is very nice though, and I'm just expecting it to get nicer and nicer as the whole system -- amps, anti-ICs, and speakers get to their 200 hour mark and beyond.

The high-q hemps ae really going to be interesting to hear as well.

Thanks,

Jim

[Louis O]

Hi Jim,

Vinnie did a great job explaining the 16-ohm drivers and the ability of the Sig 30 to drive them. No worry at all about the power output with the new drivers. I had to go 16 ohm to get the dual driver OB set up and since I have to go parallel it had to be 16 ohm.

Thanks again,
Louis