[Rusty Jefferson]

I'm willing to commit the time and effort do this but the big problem is deciding on the right horn/driver combo for my situation and specific goals. Please check out my thread. Any advice would be appreciated.
https://www.diyaudio.com/community/threads/horn-driver-combo-for-midwoofer-room-preferred-directivity-pattern.429264/

Man, that's quite the thread. I do enjoy the Joseph Crowe wood horns, so good on you there. I have two sets that I think may be more applicable to your apartment, as my living room is the same size and either one works well but larger would be a problem.

The first is the #1159. (https://youtu.be/f6S2V9D9_08?feature=shared)  He designed it as a typical ported 2 way but modified the design slightly for me to work with the SB Acoustics beryllium tweeter and Purifi 6.5" woofer that we installed in a sealed box. They are used with subwoofers. I prefer adjustable low bass because of Fletcher/Munson. I believe he will also make it as a small floorstanding speaker. The improvement from the controlled directivity compared to my previous speakers (more like what he demonstrates in that video) can't be overstated. The room is always the issue.

The other pair is the ES-800 one inch exit horns used with a very lightweight 12" Faital Pro mid-woofer and the same subs. A very compact compression driver based system that doesn't take up much more space than the #1159.

Either pair will play without audible distortion to levels well beyond what would be acceptable in your apartment and I think would be easier to implement in a room that size.  I do the asymmetrical diagonal setup. The ES-800 are more efficient and plays better with low power amplifiers. Mine use passive crossovers but the Danville is on my radar for going active. I have a friend using one with the latest AKM dacs and it sounds great.

[bellicon]

They are used with subwoofers. I prefer adjustable low bass because of Fletcher/Munson. I believe he will also make it as a small floorstanding speaker. The improvement from the controlled directivity compared to my previous speakers (more like what he demonstrates in that video) can't be overstated. The room is always the issue.

The other pair is the ES-800 one inch exit horns used with a very lightweight 12" Faital Pro mid-woofer and the same subs. A very compact compression driver based system that doesn't take up much more space than the #1159.

Either pair will play without audible distortion to levels well beyond what would be acceptable in your apartment and I think would be easier to implement in a room that size.  I do the asymmetrical diagonal setup. The ES-800 are more efficient and plays better with low power amplifiers. Mine use passive crossovers but the Danville is on my radar for going active. I have a friend using one with the latest AKM dacs and it sounds great.

Thanks for those offerings but I need to build a system that utilizes my midwoofers, as imperfectly conceived as they may be. https://josephcrowe.com/blogs/news/altec-416-8b-in-100l-sealed

Yes, everything about the room is critical to ultimate success, so much that I'm hoping to get more specific suggestions when I expect to soon get copies of the floor plans and blueprints of my apartment within the next two weeks. I suspect that it will end up being either a horn like Crowe's ES450 or possibly even the larger ES290. They offer more coverage below 5kHz than smaller horns https://cdn.shopify.com/s/files/1/0142/2848/8292/files/Screenshot_2023-10-14_170306_480x480.png?v=1697317415 but I'd hope that the narrowing coverage at high frequencies wouldn't make them sound like I'm wearing headphones and/or have sweetspot that's too much like head in vise, like the AH425 JMLC may sound, which otherwise is said to have superb imaging, and its 16" diameter may add some height with my 11 ft triangular ceiling. Have some driver ideas for a two-or three way system

The other end of the horn choosing spectrum would be the at least nowadays uncommon constant directivity horns, like the "mumped" Klipsch K510-though this knock off is minus the mumped mod https://www.ebay.com/itm/233808725468  OR something which I'd hope Troy Crowe, Weltersys and/or Cask05 might suggest. And a beryllium driver for a two-way system?

Regarding the power on/off transients which Kazoom found with DSPNexus https://www.audiocircle.com/index.php?topic=186956.msg1966210#msg1966210 ,
as this unit was at the top of my list at least for multisub (Rythmik F12) bass management and eventually for biamping a two or three way system, high level power on/off transients is the last thing beryllium compression drivers-far less my ears(!!!)-should be exposed. There are power sequencers one could use  https://gearspace.com/board/showpost.php?p=17133483&postcount=42, but shouldn't have to rely on for a DSP processor at this price point.

I was also concerned about the maximal output voltage vs. noise levels, as the DSPNexus balanced 4dbu outputs are much below that of the Merging Hapi's DA8 cards. https://www.merging.com/products/interfaces/specifications#a-k-d8-d-a-k-d8-d-p-option-card

Al Clark typically prefers answering DSPNexus related questions via phone rather then emails. And while a highly accomplished designer, I can't help but suspect a lack of forthrightness when he fails to reply to legitimate and important questions, and to the poster personally and at the original forum thread   
https://www.diyaudio.com/community/threads/exploring-high-end-component-upgrades-for-diy-active-speakers-with-dsp.415829/post-7761434 -and for that matter here as well.

 

 

[danvillesignal]

Hi Everyone,

I do prefer to have phone or video calls since I learn much more about your system and goals and I can answer a lot more questions as they come up.
I am not a writer - which is not a big surprise since I am an engineer.

I try to respond with minimal hyperbole and stick to factual statements.
My goal is to always have the dspNexus in the conversation of best sounding digital audio equipment. We are in a market of many opinions.

bellicon questions:

The dspNexus goes into a low power sleep mode that turns off the DSP, the data converters and the clocks, really most everything but the display. You can achieve a similar result with the mute control in that it will be dead quiet, but the unit will certainly stay on. The dspNexus runs warm. This is a natural byproduct of products with low noise floors since the circuits are low impedance which means high current requirements. The DSP is also fast which contributes.

We are releasing a 12V trigger - eight channel sequencer next month. Each 12V trigger output has individual programmable delay. You can use the Amp Ctrl of the dspNexus, a 12V trigger from other gear or set the unit to start from power up. We are just waiting for the enclosure metal to arrive.

The audio outputs of the dspNexus is very adjustable. It is not far lower than the Merging. They refer to +24dBu FS where +4dBu is the nominal level - Full scale would typically be about +22dB. You want to adjust the amplifier gain and sensitivities to be an optimal tradeoff between clipping and smallest signal. Usually this is a -12dB setting in the dspNexus.

Regards,

Al Clark

[bellicon]

Hi Everyone,

I do prefer to have phone or video calls since I learn much more about your system and goals and I can answer a lot more questions as they come up.
I am not a writer - which is not a big surprise since I am an engineer.

Weltersys, Cask05, Markw4, Lynn Olson, et al are certainly respected design engineers, and none of us have any trouble communicating in writing. Furthermore, all of them and other engineers I've done business with believe in the design and build quality of their products enough to state the truth about them in writing-which to me inspires great consumer confidence.

 

[bellicon]

The dspNexus goes into a low power sleep mode that turns off the DSP, the data converters and the clocks, really most everything but the display.

I didn't ask about this feature-nor did I know it existed, as I haven't  fully read the (revised) manual. But under what conditions is that sleep mode activated and deactivated? And upon wake up would there again be a loud pop heard through the speakers, like Kazoom complained about?
https://www.audiocircle.com/index.php?topic=186956.msg1966210#msg1966210

And seriously more so through high efficiency horn speakers, where hazardously high SPL transients could thereby occur?

[bellicon]

Hi Everyone,

I do prefer to have phone or video calls since I learn much more about your system and goals and I can answer a lot more questions as they come up.
I am not a writer - which is not a big surprise since I am an engineer.

I try to respond with minimal hyperbole and stick to factual statements.
My goal is to always have the dspNexus in the conversation of best sounding digital audio equipment. We are in a market of many opinions.

Regards,

Al Clark

Reiterating my concern about your apparent reluctance to affirm the performance of the DSPNexus versus competitive devices by doing so for community inspection in writing: Even more troubling is the failure to reply to Robh808's questions regarding the passive vs. DSPNexus active crossover shootout you held at Axpona this year. As Robh808 makes plainly evident, there's no proof that the shootout you held there was a 1:1 comparison.
https://www.diyaudio.com/community/threads/exploring-high-end-component-upgrades-for-diy-active-speakers-with-dsp.415829/post-7761434

In this game and at these price points only fools are content with phone chat assurances from product engineers-and also with telling questions from accomplished diyers which go ignored by these engineers.   

[HAL]

bellicon,
There are measurements online for the dspNexus 2/8 with the standard AK4493 DAC's:

https://audioxpress.com/article/outboard-dsp-danville-signal-dspnexus/

These were made before the upgrade AK4499EX DAC boards were available.