Help me choose a horn and driver

[Robh3606]

Oddly enough, the 2450SL is a 1.5" exit driver (vs 2450H/J, which are not)).

Thanks didn't know that so it's a throatless 2450?? . Odd then why do a 2451??? Did a 2450SL morph into a 2451???

[grumpy]

Hard to keep track of the variations of back-caps, magnets, ribbed/non-ribbed dias, bolt patterns, coated/non-coated, ...
Seems like someone did a photo variation comparo awhile back... subwoof maybe?

[Odd]

[Earl K]

I think these iwata horns look particularly cool ( & apparently sound good too ).

I can't say how they'll work out with your OB experiment, but I'd sure give them a go.

Like Marco says, add a tweeter ( above 10K works for me ).

[iansr]

Yes certainly looks like the 951 would be a bad idea. Hats off to Guido, even though it cost him a potential sale he advised me not to put the 951 on a 1.5 inch horn. Now that’s integrity.

[iansr]

I think these iwata horns look particularly cool ( & apparently sound good too ).

I can't say how they'll work out with your OB experiment, but I'd sure give them a go.

Like Marco says, add a tweeter ( above 10K works for me ).

Those are really gorgeous. You could be fooled into thinking they are modern sculptures.

[pos]

If you plan on using the M2 waveguide, here is an interesting comparison:
http://www.audioheritage.org/vbullet...l=1#post395445

Definitly easier to EQ than a D2430K
A 2450SL with original diaphragm might be even easier.

Depending on your amplifier choie (well, I already know your choices there ) you might prefer a 16 ohm version, to lower hiss and distortion.

[pos]

Beware. With direct radiating Woofer(s) & a compression driver+horn, you really need asymmetrical LP and HP electrical slopes (and possibly delay on the HF channel). Make sure that your analogue active crossover of choice provides the necessary flexibility. Textbook-standard symmetrical slopes (e.g., Butt3, LR4, etc.) will NOT lead to optimal results, ever!

This is actually a case in which going passive may provide MORE benefits and flexibility, not LESS.

Otherwise, of course, there is the now in-vogue "brute force" approach represented by DSP with infinitely tweakable slopes and multiple PEQs, etc.

M.

100% agree with Marco here.
Crossover slopes are critical, and require specific tricks when done with analog means without resorting to delay for alignment.

Even if the final plan is to use an analog active crossover, it might prove useful to at least use a digital crossover during the design phase.
Of course you would have to make sure you are only using things that can actually be reproduced with your analog active crossover (eg no delays...), but at least it will let you try things.
Using a simulation software would be another option.

[iansr]

If you plan on using the M2 waveguide, here is an interesting comparison:
http://www.audioheritage.org/vbullet...l=1#post395445

Definitly easier to EQ than a D2430K
A 2450SL with original diaphragm might be even easier.

Depending on your amplifier choie (well, I already know your choices there ) you might prefer a 16 ohm version, to lower hiss and distortion.

Thanks Thomas. Amongst their many virtues the Neurochrome amps are dead quiet.

[iansr]

100% agree with Marco here.
Crossover slopes are critical, and require specific tricks when done with analog means without resorting to delay for alignment.

Even if the final plan is to use an analog active crossover, it might prove useful to at least use a digital crossover during the design phase.
Of course you would have to make sure you are only using things that can actually be reproduced with your analog active crossover (eg no delays...), but at least it will let you try things.
Using a simulation software would be another option.

Yup, Initially using a miniDSP unit to determine the best settings is exactly what I plan to do. If I can’t reproduce them using the Pass crossover kit then I have a clever friend who can make me a custom analog crossover.

I may even end up with a hybrid crossover arrangement, part active and part passive. If I decide to go 3 way then just being passive between the CD and the supertweeter might be a good choice. That would still allow me to bi-amp . . .

[iansr]

I think these iwata horns look particularly cool ( & apparently sound good too ).

I can't say how they'll work out with your OB experiment, but I'd sure give them a go.

Like Marco says, add a tweeter ( above 10K works for me ).

Earl
do you know source of the wooden horns in the second photo?

[ivica]

Hard to keep track of the variations of back-caps, magnets, ribbed/non-ribbed dias, bolt patterns, coated/non-coated, ...
Seems like someone did a photo variation comparo awhile back... subwoof maybe?

Hi grumpy,

I think 2447 and 2451 as 1.5" type drivers have the same bolt patterns, while 2450-1.5 (SL), 2452, 53 and D2430K (D2) have the same bolt patters, but all of them are 1.5-inch driver "mouth" size. Some experiments have shown that 2452, 53 would give better results with 0.5-inch thick spacer between the short horns ( such as STX825 horn) and the drivers (almost the same as built-in the 2447 driver).

Regards
Ivica

[grumpy]

... worth keeping in mind as a possible area of optimization for anyone contemplating such a build, such at the original poster.
I'm sure a simple link to the experiment parameters/results would be appreciated.

[richluvsound]

... worth keeping in mind as a possible area of optimization for anyone contemplating such a build, such at the original poster.
I'm sure a simple link to the experiment parameters/results would be appreciated.

3-way JBL project using 1500al , 2450/Be , 045Be .... GEA/Yuichi Horns , 120 litre . tuned to 32 Htz

[pos]

Those 045 horns are so cute!