SEAS MR18 3-way

[Juhazi]

Even better! Again, SB seems to have better sensitivity and higher Le which suite passive design well.

 

[manninen]

Been outta hifi scene for a while, missed this project too.
So Next project some phonebooth sized?
Im thinking to relax 2019 summer too, started this thing 2018

 

[Juhazi]

Hi, sorry to say that I have no plans bubbling in my head. Perhaps a second pair of these for my elder son.

 

[djphilb]

Women come from Venus, but Hypex Filter Design and it's Help come from *nus!

I have spent about six hours of my and family's precious holiday time to get the FA board working and to start making xo. I have printed and read the HFD instructions, read the homepage (very poor) and read discussions at several forums. Installed ASIO4ALL driver, set in- and output correct, downloaded preset1 to the ampboard, but not a hiss!

The instructions are the worst I have ever read. Period.

There is no functional logic at all. At page 4 is chapter "Load measurements for speaker" but how can I have them because the amp is not even functional? Obviously I must first use some other amp and measurement system to get started and to get those spl or impulse .txt files. Why don't they say that directly????? What parameters and how should I name them?

Then later at page 5 tells to fill in your biquads and then "Load filter to DSP" ((Easy for you to say that!)

Graphical filter design starts at page 14, and it shows the downloded measurements per channel without saying how they came there.

Then finally at page 30 it starts telling about measurements "When your computer has recording capabilities.." without specifying the criteria for that. Then tells about ASIO settings. No instructions about how to set mic for measurements and what IR gating the program uses, only smoothing can be adjusted.

Obviously I must disconent the FA123 board and take measurements with REW, minidsp and some other amp to get started and to have something to load to the board.

Hypex should consult someone with at least some educational understanding to write the instructions and UI. If every discussion forum gets filled with questions about mute boards and simple basics to get started, the reputation and business gets ruined. I still want to believe that this is a good produt technically, only the UI and instructions are a catastrophe.

I 100% agree with you., it's the worst instructions ever, a complete horror show.
I bought 2 x FA122 plate amps almost two years ago to replace my failed Digidesign/PMC amps and still cannot work out how to get a simple 2 way config with a crossover at 3khz to get them going.
Wasted my money and learnt my lesson.

 

[Juhazi]

I had an opprotunity for some indoor measurements again and some fine tuning of dsp. The room is unfortunately quite problematic with hard walls and strong modes. However they sound really good, two ears and brains will get accustomed to room acoustics better than a single mic!

Hypex FA123 amp/dsp boards have had power on for some 3½ years now, without problems.

 

[Juhazi]

LR2 version with a little different eq settings and different Y-scale

Picture story of the project here https://photos.app.goo.gl/6AYTfK2GbPwogdbw6

 

[D1sco]

Did you manage to kill those high frequency resonances with the PEQ or the high order crossover? Looks really nice. The end grain in particular is to die for.

 

[Juhazi]

Cone resonances of midrange? Felt pads on edges of cone and some eq of first peak. Acoustic response is more like Duelund/elliptic at 3kHz which is fine. And because the ball is tilted, on-axis is actually almost 10deg off. The dip at 14kHz varies a lot with angle too, typical for cheap coaxials. Original MR18 uses silk dome, but my final version has aluminium.

I must work on this still, and on WM delay settings to get better match. Problem for that is indoor measurements... even indoor ground plane doesn't give clean impulse with gating long enough. Several different measurement setups are needed, but I don't know when that's possible...

 

[Juhazi]

I've been thinking about next speaker project for next spring-summer... I feel like it should be dsp-active 3-way with coaxial MT, again.

Coaxials have unmatched directivity characteristics vertically with no comb filtering and time alignment corruption. This gives them best possible imaging and uniform sound enywhere in the room. Woofer xo around Schröder 400Hz with capable closed box woofer(s) and that's it. Speakers will be a gift for my eldest son who likes heavy metal, so bass quality is very important too. I will discuss the size and shape limits with him and me might make boxes himself. Hypex FA series dsp-amps.

So - 5-6" or 10-12" mid? I'd like to try a pro coaxial this time... with 2x12" woofers? Baby slim version of Taipuu?

 

[D1sco]

If you haven't seen the Bitches Brew by Perry Marshall, I highly recommend checking it out. Not a cheap project, but the parts and assembly are top notch. Your project and his are both serious inspirations for my own designs.

 

[jzl]

Check new PHL 2534Mdn from tlhp. Flat suspension coax with flat magnetic system to get better cone and compression driver alignment.

 

[Juhazi]

A link to my new thread, Big coaxial 3-way

https://www.diyaudio.com/community/threads/big-coaxial-with-rcf-cx12n251.393313/#post-7203199

 

[Juhazi]

Directivity 0-180¤ made with VCAD from REW-measurements (indoor)

 

[Juhazi]

Here are the speakers at their end user's room today five years from finishing. The TV is 50".
Room has concrete walls so low modes are terribly strong and also positioning is restricted. But they look nice and sound good. No need for subwoofers, but notice how different is the low bass of left vs. right speaker.