[Poultrygeist]

Another thing I like about the Ashly is that in addition to XLR's it has 1/4 TRS which means you can use your own cables with inexpensive 1/4 TRS adaptors. I think I paid $5 for 10 TRS adaptors shipped.

[danvprod]

Cool, thanks @Poultry --

I've seen your threads on both of your systems. With the Fostex, you said you are using a .47 uF cap? Did you mean 4.7 uF? I think .47 would be like 42,000 k cutoff frequency if I am calculating correctly?

Cool on the Ashly, have you found that it is provides sufficient control to do things like notch out a dipole peak and counter the roll-off? I suppose because you don't have the flexibility of the miniDSP, you'd have to design around these features.

So I'm trying to understand your signal flow.

Signal in -> Ashly (which is a 2-way x-over) -- crossover point for the low is 1.5k and that goes into the Yung amp, which has a HP of 200 Hz. The HF of the Ashly is set to what? And that powers the 12" Beta and passively crossed-over Fostex?

Do you find that 200 Hz x-over point integrates well with the Beta on your flat baffle? And are you running the beta full range? Does that integrate well with the Fostex?

Thank you very much for your insight, your systems are very much an inspiration for my build.

[Poultrygeist]

Thanks dan,

My Ashly is a 2 way with the sweet spot between the HF Beta and LF Alpha set at 1.5K (1.75K is also good ). I don't have near the flexibilty of the miniDSP but I enjoy being able to tweak the frequency or the input/output levels and response ( akin to slope control ) with the turn of a knob. Even though it's 2 way stereo it has a sub connection which allows use of a bass cube to augment the H-frames. The H-frames go down to 40hz and my 8" Dayton bass cube covers what's below.

The tweeter runs off the Beta with a .47 cap which takes the hot sizzle off the top. The highest value I think I've used between a full range and a parasitic tweeter is 1.5 uF.

The Yung plate which drives the Alphas is set as high as possible ( 200Hz ) which allows the Ashly to come under that. I can't turn off the Yung's crossover but this works. 

The Beta/Fostex tweeter is the best blend I've come up with so far. It seems to be a popular combination.

I see that the latest version of the Emerald Physics has switched to the Beta 12LTA with a compression horn riding piggy back. 

[danvprod]

Thanks @Poultry

I guess I am not understanding.

If the Yung plate amp is running from 40 Hz - 200 Hz

and the x-over from the Ashly is at 1.5 kHz between the Beta and the Alpha, what is covering 200 Hz - 1.5 kHz?

Also, I understand about the super tweeter, you are just running it very very high to add some sizzle. 1.5 uF would be like a 13.3 kHz x-over, 1.0 uF would be a 20 kHz HP, but then it's only down 6 dB @ 6.5 or 10 kHz.

Any L-pad needed between the Beta and the Fostex?

Thanks for the clarification.

[Poultrygeist]

My 2 way actives have one frequency range control for the left channel and one frequency range control for the right channel. I don't  use a formula to determine how to set the frequency. I just tune by what sounds right to my ear.

[danvprod]

I understand. And I get the .47 uF on the tweeter now. Because of the sensitivity difference, it ends up being down -13 dB or so at 10k, with a rising response, so this will integrate with the natural roll-off of the Beta.

On your Ashly, there is a /10 button, which would make 1.5 kHz on the dial actually be 150 Hz. That makes sense to be as a crossover with the Alphas. Maybe that is what you have it actually set to?

I also see that the Beta 12 LTAs are available on Amazon with free shipping... hard to not pull the trigger on those

[danvprod]

Played around with REW this morning, equalizing a bit at the listening position and trying to shape the response to the B&K house curve. Also took a did a bit of work on the crossover.

Couple of modifications:

• Changed Alpha H-Frame to 125 Hz, 12 dB/Octave LR
• Trimmed the Betsy down 5 dB to match the Alpha (Recall that MJK said that the h-frame needs to be about 8-10 dB more sensitive than the full-range to match with his h-frame design. I am finding this to be the case.
• Changed the Betsy to 250 Hz, 12 dB/Octave LR, flipped phase, mainly to smooth out the 150-300 Hz range, where there was some build up.
• My 6 dB/octave dipole roll-off compensation filter is now the only EQ I am doing on Betsy

So I made the measurements at the listening position and did the Auto-EQ to match the B&K house curve, and this is applied as an EQ before the crossover. You can see the main deviation from the curve really is above 8 kHz, where I think using the Fostex Super Tweeter will be the answer, the one @Poultry recommended with a .47 uF cap. So I will scout eBay for that.

[JohnR]

Cool. How does it sound?

Is this the tweeter? http://www.madisoundspeakerstore.com/bullet-tweeters/fostex-ft17h-horn-super-tweeter/

[Poultrygeist]

It looks very close to the Realistic 40-1310A.

dan,

Have you considered cutting out the Betsy's dust caps and adding a phase plug?

I plan to as soon as I can get access to a lathe or find some small wooden eggs. I think I recall Planet10 selling them for the Betsy.

After my success with smoothing out the Beta's I'm sold on phase plugs for whizzer cones.

[danvprod]

@JohnR -- They sound better than they did. I like the way that the h-frames sound, and the betsy sound a bit less 'shouty' than they did (I think it was because of the 1kHz, 3.5 kHz and 10kHz peaks that were notched out) and also because of the 150-300 Hz build-up.

Measuring at the listening positioning worked well. Thanks for the link for the super tweeter. I was actually looking for the 40-1310A (the one made in Japan).

@Poultrygiest -- Yes, I think I'd like to go with the phase plugs. Looks like @Planet10 has the phase plug blanks for $20/pair. Other option may be be a dowel? I'd like to try that before replacing the driver.

And I will try the super tweeter too.

[guest42212]

re: phase plugs

You could try a socket ala DecWare

[danvprod]

Ha! I love it. Thank you for the suggestion. Sounds like a great first plan. I did touch base with David at Planet10 and he does have a couple of Phase plugs left for $30 shipped.

[Poultrygeist]

This thread got me thinking about the Betsy's so I brought them in from the garage, dusted them off and tried them with the Ashly. I connected them to the 2a3 Paramours and the Alphas to the Yung plate amp. The frequency range on the Ashly always sounds best switched to the divided by 10 option and with the Betsy's I found 1.20K to be the sweet spot.

The Betsy's have always sounded very good but I don't remember them sounding this good. Perhaps it's the Ashly as in the past I've always run them full range with the plate controlling the Alphas. Sometimes I use just a 80hz filter as shown in the picture. But maybe it's the better amp I'm not sure.

I don't know if the Betsy's need a tweeter as they play pretty high but I've got several I may try including the Neo 3's with covers removed and a Vifa. The Neo 3's worked well with the Tang Bands but I had to drive them with their own t-amp. Bi-amping with an active is complicated enough but tri-amping gets real crazy with all the wiring.

[danvprod]

Nice to hear that -- the betsy drivers are pretty sweet. In the bigger baffles , like you have there, they need no dipole roll-off compensation, like I had to do on my smaller baffles, so the Ashly makes perfect sense.

I bet those Paramours are nice.

[Poultrygeist]

Thanks dan for reviving my interest in the Betsy's.

A pair of Betsy's + a pair of Alphas cost around $250. I spent over four times that on a gorgeous pair of Zu's that didn't sound as good. 

[danvprod]

A pair of Betsy's + a pair of Alphas cost around $250. I spent three times that on a gorgeous pair of Zu's that didn't sound as good. 

This arrangement really has no business sounding as good as it does 

You can build this speaker setup for < $400, even if you had to buy tools as I did. I also used 'nice' 3/4" Birch ply. If you built them from MDF or particle board, you could prob save another $40-$50 on materials.

[Poultrygeist]

Folks could build the flat baffle Betsy/Alphas with just a jig saw for the speaker holes.

Home Depot will make all the straight cuts for free with their wall saw if you buy their plywood or MDF. I was surprised they would cut MDF but they will. 

[danvprod]

Started the process of finishing the h-frames. 3/8" radius on the edges, primed and applied a patching primer to all the edges.

Thinking about the best way to finish these -- either thinking a satin black or a textured truck bed liner. The textured finish would hide the many imperfections of my build better, but the satin black may be good enough.

I also went ahead and ordered the Mark Audio Alpair 10.3 drivers to try something new. I was still not thrilled with the sound. Something is missing and I can't put my finger on it. I think the LFs provided by the h-frames are good. I still could use a bit more bass weight. For jazz and small ensembles it sounds sublime, but for more dense music something is missing.

I am hoping that the Alpair will have a bit more detail and HF extension vs. the Betsy. I am also hoping that the presence region will not be so boosted like the betsy is. I plan on mounting the Alpair on a 16 x 20 flat baffle, 8" down from the top and 2" off-center. The wider baffle should also push the roll-off down to about 200 Hz, where it can integrate well with the Alpha without needing the 14 + dB of boost at 90 Hz that I am currently doing in the Mini DSP.

The other to-do for sure when this gets all built back up is the properly time-align the driver.

Looking forward to suggestions on the finish, I am not the best painter/finisher in the world. I just want something that will look professional and be durable.

[danvprod]

FYI --

For the baffle, I am going with the MJK design -- http://www.quarter-wave.com/Project08/Jordan.pdf

And this is the texture finish I was thinking for the top coat -- http://www.lowes.com/pd_17750-90-248915_0__?productId=3184045&Ntt=truck+bed&pl=1&currentURL=%3FNtt%3Dtruck%2Bbed&facetInfo=

[mcgsxr]

I have often used the textured truck bed liner spray cans to cover up my woodworking "skills" when it came to finishing speakers.  I found it tougher than normal paint for minor wear and tear, and very effective at fooling the eye from a medium distance of 3-4 feet.

Here it is on the face of an amp I had modified.  This worked really well, as the surface was actually smooth etc.