Help me choose a horn and driver

[ivica]

Many thanks ivaca, those links are really helpful. Any particular reason you suggest the H95HF rather than the H1010. Also I’m starting to think a 3 way is worth considering, in which case the K95MH looks interesting!

Hi iansr,

I have no experience with H1010, but for me, PTH95HF is quite good with the mentioned driver.

regards
ivica

[iansr]

@robh3606
i just came across a post from you on WBF where you said :

The system may be DSP but the M2 waveguide is very good and works very well with a passive crossover. Here is a raw measurement of a 476Mg on the M2 and a Leap crossover solution based on Greg Timbers "Key Filter" design. With this compression driver all you need is a series filter and HF bypass and a single parallel notch filter to do the compensation to flatten the response on the waveguide. This waveguide is actually very similar to the 2344 and PTH1010.

Thats really interesting! The M2 DSP has such a high number of EQ points that I thought it would be really dificult to create a passive crossover for either the woofer or the CD/waveguide. Does using the 476Mg makes it less complex?

[Robh3606]

Thats really interesting! The M2 DSP has such a high number of EQ points that I thought it would be really dificult to create a passive crossover for either the woofer or the CD/waveguide. Does using the 476Mg makes it less complex?

Well I guess it depends on the compression driver. Like any good CD horn it's un-equalized on axis output should match the power response of the driver. Tale a look at the difference between the stock M2 compression driver and the 476Mg. The 476 is much better behaved IMHO as are a 2451/52. I am also not going for ruler flat response There is some ripple between 2-4k that you could DSP out but I wouldn't bother.

Rob

[Earl K]

That certainly looks real nice Rob.

Reality-wise, can the OP ( Ian ? I suppose ) even buy these 476Mg drivers?

Or are they embargoed ( only to existing owners of speakers that contain this driver ) ?

[iansr]

Thanks Rob. How do you think a 2452 + Truextent compares to a 476Mg or even a 476Be?

[marco_gea]

Thanks Rob. How do you think a 2452 + Truextent compares to a 476Mg or even a 476Be?

Actually, a 2450SL + Truextent BeX4008 diaphragm would be the best candidate.

The 2451 > 2452 > 2453 are progressively cheaper versions of the original 2450s...

Please note that due to the Truextent's PEEK (i.e., plastic polymer) surround, though, the top octave (>10kHz) will be more attenuated (but without any peaking, which IMHO is a good thing).

[Robh3606]

Thanks Rob. How do you think a 2452 + Truextent compares to a 476Mg or even a 476Be?

Hello iansr
Well that depends on how much roll off there will be in the last octave. The Be sounds great but it also rolls off with the Magnesium and Ti diaphragm's they actually roll off but peak a bit out in the 10-20K region. That peak is not as clean like the Be. That peak actually makes them easier to do the network for if you are not planning on using a Bat Killer out to 40K. I was fine with the roll off using a 2344/2425 again OK with a 2435/PTH1010 you may not be. It's a personal choice. Take a look the attached plots.

Reality-wise, can the OP ( Ian ? I suppose ) even buy these 476Mg drivers?

Hello Earl

I doubt it I was lucky to get mine that's why I was suggesting another available driver with a similar response.

Rob






Rob

[iansr]

I’m strongly attracted to using the M2 waveguide. As far as the Driver is concerned, I’m considering Marco’s suggestion of a 2450SL + Be, but the Radian 951 + Be is also very tempting, and cheaper! Guido reckons the Radian is as good as the 476Be.

[Robh3606]

Hello iansr

Are you going active or passive?? Active it really doesn't matter but if are trying to go passive make sure you are comfortable with the HF roll off using the Be drivers. Watch the mounting bolt pattern on the Radian. You are probably going to need an adaptor plate going from 1.4-1.5 throat diameter.

Rob

[iansr]

Hello iansr

Are you going active or passive?? Active it really doesn't matter but if are trying to go passive make sure you are comfortable with the HF roll off using the Be drivers. Watch the mounting bolt pattern on the Radian. You are probably going to need an adaptor plate going from 1.4-1.5 throat diameter.

Rob

I’m going to go active, but analogue not DSP. I was going to ask about the 1.4” of the Radian. Is an adaptor plate likely to adversely affect the performance do you think?

[marco_gea]

if are trying to go passive make sure you are comfortable with the HF roll off using the Be drivers.
Rob

That, or add a supertweeter. In my experience, the latter invariably leads to superior results, no matter what (compared to using compression drivers that "peak" in the top octave - as such peaking is always linked to parasitic resonances). Others may and probably will disagree, and that's all right with me ;-)

Marco

[marco_gea]

I’m going to go active, but analogue not DSP.

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.

[marco_gea]

I was going to ask about the 1.4” of the Radian. Is an adaptor plate likely to adversely affect the performance do you think?

Not the adapter plate per se. But the (potential) double mis-match in wall angles may well do so.

[Robh3606]

Hello iansr

You ever do anything like this before?? Analog is a great way to go but it's going to greatly complicate things. I would also try to avoid an adaptor plate for a throat transition. If you plan on using a 1.5" horn use a 1.5" driver.

Actually, a 2450SL + Truextent BeX4008 diaphragm would be the best candidate.

Hello Marco

The 2450 is a 2" throat can't use it with the M2 a throatless 1.5" driver is your best bet


Rob

[grumpy]

Oddly enough, the 2450SL is a 1.5" exit driver (vs 2450H/J, which are not)).
Definitely watch out for bolt hole pattern differences though, between the various 1.5" exit drivers.