Other sub amp for Gallo Ref3 secondary voice coil?

Spurzheim:

What kind of tube amp are you using? I am going to play with my SET amp when it arrives, but don't know if 7 watts will be enough...

I'll be using it with the Gallo SA amp --I'm signed up for one as soon as they arrive from my dealer (supposedly, they're on the water and due in soon).

With the SA, I'll have 3 amps to play with:
MacCormack DNA 0.5 Platinum (from SMC audio)
Dared VP 300B SET
SA

I have seen people use other Xovers and/or low pass filters and all have had success.

Hi Bgrazman - thanks for the response. I am using an Onix / Melody SP3, which is 38 WPC. It can shake the walls, but knowing that I can get another 10 Hz of extension makes me want to try a secondary solid state amplifier.

Do you mind me asking where you have seen others use filters/crossovers? I did some searching before the initial post, but came up with nothing.

Cheers!

I used 2 spare channels on a multichannel amp and used an Outlaw Audio ICBM cross over set to 40hz. It worked fine.

I gave up waiting for the Gallo amp and ordered a Hsu 500A (500w) subwoofer
amp with a 43 Hz crossover module. I had a 30-day moneyback period to
decide, and really like the thing. It's a SERIOUS amp and an ideal match for the
Ref 3s, which I'm driving with 12 wpc SET monoblocks (845 output tubes). The
500A costs $749 direct from Hsu, approx. $200 less than the Gallo sub amp.

Originally, I was using a Fosgate Audionics 100wpc amp with a Hsu electronic
crossover on the second voice coils, but this setup didn't have nearly the
authority of the 500-watter. Good luck, Dave

PS You need to break in those second voice coils just like the rest of the
speakers . Play 'em loud and hard.

Spurz,

I can't find the threads, but I'm sure it was here.

I'll keep looking

Dopogue,

How hard do you have to push your 845's? (the amp I have coming is based on the 300b tubes).

Thanks,
brent

My SET monoblocks (845 outputs, EL34 drivers. 6N7G inputs) designed and built by a friend, have huge trannies and the 12w output is conservative. They never run out of steam but are rolled off at the bottom so that they don't have to waste power trying to drive that last octave. That's what the sub amp is for.

All you can do is try yours and see if they have enough oomph. Certainly the Ref 3s love tubes. Good luck, Dave

I purchased a pair of plate subwoofer amps from Parts Express for about $125 each (part of a DIY subwoofer kit). I think the version I bought have about 200 wpc. The plate amps, of course, have a variable low pass filter, phase and level controls. I believe the cross-over is 24 db/octave. I ran the specs of these amps by JD at Gallo. He checked with Anthony and said they should work fine. They certainly seem to, though I haven't compared them to other amps. I'm sure they don't have the authority of a higher quality amp, but this was a pretty inexpensive solution to get a true dual mono power source for the second voice coils.

-- Rich

"I purchased a pair of plate subwoofer amps from Parts Express for about $125 each"

What a fantastic idea Rich. I will look into that...

Hello
What about volume control with the Gallo SA amp.? Then if another amp is used will volume control work O.K.
I guess it would work just as if you had a sub hooked up via high pass??
thanks
Matt

I was contacted by a Ref 3 owner who had tried inexpensive subwoofer amps (sounds like the ones mentioned above, but I'm not sure) and found them too wimpy to do the job. They work, but without the authority of the Hsu and ( I presume) Gallo sub amps. Strictly hearsay, of course. Dave

08-30-05: Richs
I purchased a pair of plate subwoofer amps from Parts Express for about $125 each (part of a DIY subwoofer kit). I think the version I bought have about 200 wpc. The plate amps, of course, have a variable low pass filter, phase and level controls. I believe the cross-over is 24 db/octave. I ran the specs of these amps by JD at Gallo. He checked with Anthony and said they should work fine. They certainly seem to, though I haven't compared them to other amps. I'm sure they don't have the authority of a higher quality amp, but this was a pretty inexpensive solution to get a true dual mono power source for the second voice coils.

-- Rich

Rich et al:

- I maintain that the amplifier you purchased from Parts Express is essentially the same one used in each channel of the Gallo SA. Read the specs on this particular model at the below link and see if you don't agree:

DAYTON SA240 240W SUBWOOFER AMPLIFIER
Part Number 300-804

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=300-804&ctab=4#Tabs

This mono amplifier is rated at 240 watts rms into 4 ohms at 0.1% THD. This spec is identical to the spec for the Gallo SA - see the user's manual for the Gallo SA at their website. Note that the Gallo Sa is rated into 4 ohms, not 8, as is this particular PA. Many other specs of the units are identical. Too big of a coincidence.

One key difference (other than the fact that there are two identical 240w channels in the Gallo SA) is that the Gallo product adds the EQ control, which allows tailoring the boost at about 26 Hz by -3 dB to +6 dB. In my opinion, this is a key feature that really makes the Gallo product much more useful than a PA without this feature. Note that this is different than simply turning up the gain on the SA channel, which boosts all frequencies in the passband by an equal amount. The EQ control, as can be seen by the frequency response curves in the Gallo SA users manual, varies the Q of the circuit providing a localized boost in the mid 20 Hz region, just where it's most needed.

Of course, anyone with a knack for designing and building simple filters could put together a smiliar control to be used with the Dayton product, or perhaps there's one that can be bought off the shelf. In any event, given the price of the Dayton PA, one could purchase two of them for $240 plus shipping, which is ALOT less than retail of the Gallo unit.

I would also suggest that the use of the Hsu amp described above, while it may improve the bass performance of the system, would not be expected to provide the performance of the Gallo SA without anything equivalent to the Gallo amp's EQ control.