Ricci's Skhorn Subwoofer & Files

[SME]

Thanks again for the suggestion.  I am thinking along similar lines, though I do still need to be mindful of the round-overs.  I'm also keeping the bracing dividers to 12mm.  I'm trying to keep the weight down.

[peniku8]

13 hours ago, SME said:

Thanks again for the suggestion.  I am thinking along similar lines, though I do still need to be mindful of the round-overs.  I'm also keeping the bracing dividers to 12mm.  I'm trying to keep the weight down.

Are you talking about the SKHorn or a different project? I don't think flared ports are gonna save you from vent noise (below 20Hz) when running with the 1 vent per side config, and I also don't think that flared ports are needed when you're running with 2/3. I can push the drivers to Xmax at 20Hz with 1 vent open per side and not get any air noise.

[SME]

10 hours ago, peniku8 said:

Are you talking about the SKHorn or a different project? I don't think flared ports are gonna save you from vent noise (below 20Hz) when running with the 1 vent per side config, and I also don't think that flared ports are needed when you're running with 2/3. I can push the drivers to Xmax at 20Hz with 1 vent open per side and not get any air noise.

It's for a different project, a plain-vanilla vented cabinet.  I'll probably start a thread for it soon.  Either way though this discussion is relevant to the Skhorn.

Vent round-overs certainly won't prevent chuffing, but I believe there's evidence that round-overs can improve flow characteristics at moderately high velocity, perhaps allowing an extra 1-2 dB before chuffing does become noticeable or before compression becomes serious.  It's a minor detail but worth it IMO when vent area is a bit limited as it is with both the Skhorn and the design I'm working on.

Also, I care more about avoiding/reducing compression, which sets in quite a bit sooner, than I do about chuffing.  With compression, the spectral balance is distorted substantially as level is pushed higher.  In use-cases where high accuracy/SQ is important, this is likely not acceptable, which effectively limited usable output to a level that may be much less than when chuffing because audible.

[peniku8]

8 hours ago, SME said:

It's for a different project, a plain-vanilla vented cabinet.  I'll probably start a thread for it soon.  Either way though this discussion is relevant to the Skhorn.

Vent round-overs certainly won't prevent chuffing, but I believe there's evidence that round-overs can improve flow characteristics at moderately high velocity, perhaps allowing an extra 1-2 dB before chuffing does become noticeable or before compression becomes serious.  It's a minor detail but worth it IMO when vent area is a bit limited as it is with both the Skhorn and the design I'm working on.

Also, I care more about avoiding/reducing compression, which sets in quite a bit sooner, than I do about chuffing.  With compression, the spectral balance is distorted substantially as level is pushed higher.  In use-cases where high accuracy/SQ is important, this is likely not acceptable, which effectively limited usable output to a level that may be much less than when chuffing because audible.

Can't want to see what you're up to! When I think about the SKHorn I think about large venues with the capacity for over a thousand people, and there probably only the first two or three rows might notice vent noise. The roundovers are not much work thou, so why not just add them. I also placed roudovers on my current 12" project at vent entrance and exit, as far as it was possible for me. Very easy job with a roundover bit.

[peniku8]

Got the ok from @Ricci to post the metric SKHorn plans I made. It's a compact 4 pages and I built my cab with these.

I made the horn bracing from one piece as I found that to be less work, even without a CNC.

 

SKHorn Metric Drawings.pdf

[SME]

Nice.  Maybe @Ricci can attach that to the first post as well.

[Ricci]

13 hours ago, SME said:

Nice.  Maybe @Ricci can attach that to the first post as well.

Done!

[peniku8]

Here is the requested comparison, I included the 5 most prominent drivers for this cab. It already looks like a small mess, which is why I didn't include more.

 

 

 

[klipsch]

On 9/24/2019 at 11:41 AM, peniku8 said:

Here is the requested comparison, I included the 5 most prominent drivers for this cab. It already looks like a small mess, which is why I didn't include more.

 

 

 

Any chance you could throw the 18sound driver in there? 

[peniku8]

10 hours ago, klipsch said:

Any chance you could throw the 18sound driver in there? 

As for max output it's essentially the same as the DS or the LaVoce, but falls about 1db behind under excursion limit and is less than .5db ahead when power limited.

I'm unsure if the Leb of 0.001mH is correct @Ricci

 

[klipsch]

1 hour ago, peniku8 said:

As for max output it's essentially the same as the DS or the LaVoce, but falls about 1db behind under excursion limit and is less than .5db ahead when power limited.

I'm unsure if the Leb of 0.001mH is correct @Ricci

 

Thank you! 

[peniku8]

@Ricci How would the K20 fare with 4 21DS115-8 in parallel on one channel? Impedance minima would be around 1.3 Ohm. I'm thinking about getting a K20, but if it's not performing well with that load I could also get a K10 and go for a 4 Ohm configuration. The difference between K20 and K10 is much less at 4 Ohm than at 2 Ohm.

[Ricci]

On 11/1/2019 at 6:24 PM, peniku8 said:

@Ricci How would the K20 fare with 4 21DS115-8 in parallel on one channel? Impedance minima would be around 1.3 Ohm. I'm thinking about getting a K20, but if it's not performing well with that load I could also get a K10 and go for a 4 Ohm configuration. The difference between K20 and K10 is much less at 4 Ohm than at 2 Ohm.

It depends. The K20 will run stereo at 2 ohms, but it will limit long bass notes into low impedances considerably. Buss pumping can be a problem. The exact impedance and phase of the load and the bass content used will determine how well it does. I really recommend bridging the K20 or K10. They perform better with heavy duty signals into low impedances when fully bridged. 

[peniku8]

8 minutes ago, Ricci said:

It depends. The K20 will run stereo at 2 ohms, but it will limit long bass notes into low impedances considerably. Buss pumping can be a problem. The exact impedance and phase of the load and the bass content used will determine how well it does. I really recommend bridging the K20 or K10. They perform better with heavy duty signals into low impedances when fully bridged. 

The plan would be a symmetric load anyways (8 drivers total), so bus pumping shouldn't be much of an issue. 4 drivers per channel on a K20 sounds like a good match to me. If that's not enough, doubling both would be the alternative. 16 of these drivers should be plenty for a lot of situations... X4L surely looks nice for that application, but since it's so new you hardly find it used anywhere.

[peniku8]

Question about (CNC) accuracy: when producing the hatch plate and the back panel, how much of a gap should I leave when I'm planning to coat all surfaces with Duratex? Would 1mm be enough?

[Ricci]

3mm or so undersized should work. Depends on how many coats of Duratex though. If coating both surfaces multiple times you may need a bit more. 

[sakkara]

  Hi Everyone,

First post on the forum. Read through this thread a few times and im thinking of building a skhorn. Im looking for a cabinet /driver/amp combination that can handle musical  and complex bass at low hz, early dub with alot weight in the low end or the UK hardcore continuum with complex varying deep sub bass lines. 

What sized space do you think a single skhorn would power well?

I used to go to a night in a basement, about a 5x10m across dance area, single large cabinet stack at the back, it would get a solid hi-fi club sound  with good power in the low end.

Would it be be better to plan to build a couple of skothorns to get this kind of sound in a similar area?

This will affect how much money  i allocate to the amp.

Which components o you think has a highest impact on the quality of the sound, the size/number of cabinets, the quality of driver, or the quality of the amplifier? 

Quality of the sound is my highest priority it doesn't have to be the full chest shaking loud that you will get out of RC1.

Nice one 
Sakkara

[Ricci]

3 hours ago, sakkara said:

  Hi Everyone,

First post on the forum. Read through this thread a few times and im thinking of building a skhorn. Im looking for a cabinet /driver/amp combination that can handle musical  and complex bass at low hz, early dub with alot weight in the low end or the UK hardcore continuum with complex varying deep sub bass lines. 

What sized space do you think a single skhorn would power well?

I used to go to a night in a basement, about a 5x10m across dance area, single large cabinet stack at the back, it would get a solid hi-fi club sound  with good power in the low end.

Would it be be better to plan to build a couple of skothorns to get this kind of sound in a similar area?

This will affect how much money  i allocate to the amp.

Which components o you think has a highest impact on the quality of the sound, the size/number of cabinets, the quality of driver, or the quality of the amplifier? 

Quality of the sound is my highest priority it doesn't have to be the full chest shaking loud that you will get out of RC1.

Nice one 
Sakkara

Hello Sakkara...Welcome. 

In my opinion total speaker size/number of cabinets is most important especially in the bass region. Driver quality and synergy with the cabinets is second. Amplifier quality is 3rd.

How many cabs to use depends on the room, application and how loud the average playback level is. For any type of live, DJ, dance club type of situation I'd recommend at least 2 Skhorn's or 4 Skram's or Othorn's as a starting point. Double that amount to really get the place rocking. 

[sakkara]

Ok great, thanks ricci thats super helpful! i will aim for 4 in the long-term and will plan drivers and amps around that.  
Im currently thinking of going with the B&C 21SW152-4.  I reckon im going to start with a single cabinet and
see how i find the process and results. 
Ive been reading through the threads on amps, how well do you think this would work with a skhorn?
https://djcity.com.au/product/behringer-nx6000d-power-amp-with-smart-sense/?gclid=CjwKCAiAlajvBRB_EiwA4vAqiNB3Ik_NHgGRrWRio1k-RCDxNb-UAQg1B4OOf6AH48mY4u8Il71H1hoCK2sQAvD_BwE

[peniku8]

The 2 channel 6000D is a bridged version of the 4 channel amp. One channel will output a little more than 2KW bursts into 4R but seems to be able to sustain like 1.5KW (according to notnyt's tests on AVS). If you hook up the 2nd channel as well, those numbers drop by about 25%. The SKHorn is fairly efficient and you said that your priority is not SPL, so I think the Behringer should be a good start for you.

The amount of cabs Ricci stated is not a 'requirement' for SPL, but rather to even out room response and have higher flexibility I'd guess. Even one SKHorn should be enough to exceed 130db in the room size you mentioned. That's a tiny room for so much sub. But more is always better for sure!

I'd say build two SKHorns and use it with the NX6000 at first to save some money. If you want to upgrade to an amp with more power in the future, you'll have to spend a lot more money compared to the Behringer. There is quite a big price gap in that market if you don't count the China clones. Maybe you're lucky and you can snatch a K10 for under 2 grand used.

[M_J]

hi guys,

new here.

is it possible to use just half of the design? for one speaker?

thanks.

[klipsch]

6 hours ago, M_J said:

hi guys,

new here.

is it possible to use just half of the design? for one speaker?

thanks.

It is possible. Oversimplification: The skram follows this concept, except Ricci made the skram slightly bigger (2 skrams are slightly bigger than one skhorn) and Ricci modified the ports to accommodate more tuning options. 

[Alexrmont]

I am planning on building six of these for a mobile stage I use. We currently have access to pk cx800 subs and stack them. By reversing polarity on the bottom one, we get more push forward. Is this something we can do with the skhorn, or does it not need that since these are horns as opposed to ported boxes. Thank you for all of the work you have put into this design. 

[peniku8]

3 hours ago, Alexrmont said:

I am planning on building six of these for a mobile stage I use. We currently have access to pk cx800 subs and stack them. By reversing polarity on the bottom one, we get more push forward. Is this something we can do with the skhorn, or does it not need that since these are horns as opposed to ported boxes. Thank you for all of the work you have put into this design. 

I'm guessing that you're talking about a Cardioid setup here, but there is alot more to this than simply flipping the phase of a sub in a stack.

There are many way to do this, but most common would be either stacking subs in two rows (needs more floor space and additional delay+measurement work) or physically turning every 3rd or 4th cab around so that its rear faces forward. You'd then flip the phase and delay the signal according to the depth of the cab. Delay can vary, so its best to just try different settings, measure and listen.

Typically, the 2 row setup increases front output and rear rejection and the latter one I described just improves rear rejection. In short, yes, it can be done. It will require some work and knowledge thou and if you come here asking if this would work in the first place, it'll probably be your job of setting that stuff up and aquiring the necessary knowledge. But as Leonard Lauder once said:

Quote

If I don't learn something every single day, it's a wasted day.

Theres alot of crazy stuff you can do to array subs.

[pazo]

I have 2 pieces RCF 21n401  .Any suggestions?