Aleph 4 vs Aleph 2 for Driving slotted Open Baffle Bass Section

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I would like to drive the bass section of the Slotted Open Baffle loudspeaker with more authority. The six 8" drivers are 12 ohm and wired in series/parallel for around 12-16 Ohm. It's currently driven by a F5 with no thermistor and protection circuit.

If the drivers were wired in parallel, then series, for lower combined impedence, would there be more current to drive the speaks to a noticablely higher output? This would be the easiest option, obviously.

Another option would be to build an amp with more power. I have Aleph boards and could make either an Aleph 4 or 2. The voltage difference is 3v, 45v vs 48v, but one handles lower loads better. Is it the A2? They have the same number of output mosfets. Both are good for 100w at 8 ohms, I believe.

Like to hear your thoughts and experience.

Thanks,

Vince
 
why not F5Tv3(v2)?

I would if there were working boards available at a reasonable price.
Nothing in the store yet and the last quote I received for boards was very high.

I also have AX and AJX boards, but they are more complicated and would like to use them for the upper frequencies.


Aleph 60 would be a better choice ...

The A60 is 60w into 8 ohm, and I don't have a schematic for it. Won't be hard to adjust for 60w. But, just looking for raw power. I'd try the A100 BJT, but it's BJT. If the output were high bias FETs, I'd try it.

Would be more apt to go for the F5T. Have F5 boards sitting around too. 😉

Thanks.
 
Aleph4 is basically lower biased Aleph2, made so it'll fit in a stereo chassis. Aleph2 is dual mono. Was just looking through the service manuals for the A2/A4, it states that the output stages for each are biased at 'slightly greater than 3 amps', but the A4 dissipates 250W/ch vs A2's 300W/ch. The 2 will do 160W/4ohms, there wasn't a spec for the A4 into 4ohms. I'd say go for 2, Nelson has stated somwhere on here that it's 'the most neutral of the bunch'. I built a Aleph5 biased @6A once, had plenty of grunt until it went up in smoke. You know the rules, big PS, big sinks, big bias..etc.
 
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I have open baffles also. The bass (8 ohm) has been driven from diy F3, and F5. With these amps, the bass has lacked "authority" (to use your terms).

I considered boxing and porting my OB's.

Until I drove the bass with an F5c. It made a noticeable difference, and I am looking forward to other higher power amps on bass duty. I like my OB's, and they are staying.

I'm now collecting parts for F5T V3, and have an SE Burning Amp in progress. It's a disease.
 
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