Ricci

24 minutes ago, Leimahmood said:

what will b good for me

dayton um18 or 21sw152 is fine

here in our country both price are equal

If the price for you is the same get the B&C no question. I wouldn't even think twice.

On ‎2‎/‎7‎/‎2019 at 3:30 PM, Leimahmood said:

on uper post a member mention that u working on a single driver version skhorn so actually my mind was on skhorn

i have zero idea with building my own box how to calculate driver space and make a box

can u plzz make a box size for this driver which tuning u think is fine fir these

i have no problem with big box thanks

I don't have a single version of the Skhorn style of sub done. I'm going to work on it again soon but it will probably take me months to get the SW's design and prints done and it may not be what you are looking for anyway. It's not supposed to be a HT sub.  I wouldn't wait on it.

It should be fine powering 2 21SW152.

For HT in a home you may want to build a simple ported box with a tuning in the 15-20Hz range.

Nice collection of woofers there!

Paul,

We briefly discussed this before but I did receive a pair of 21Ipal's that had a ticking sound coming from inside the motor. It was the first pair I ever received. Sounds exactly like you described almost like diesel a engine and got worse with level. Also that pair had a different gasket material and the BL was quite a bit below spec on them. Almost like an old production run or something. My second set did not behave the same way. BL was up where it should be and no ticking sounds. Bennett exchanged the first set of drivers after I sent some video and explained it to him.

I still don't know for sure what the ticking sound is. I've never had an issue with any other B&C woofer.

I would not assume that those motors are identical...Most of the B&C bass drivers used 2 layer coils, inside/ outside wind with split winding on the outside layer only. Quasi / mini LMT design basically. Some pro woofers still utilize single layer coils. Note that they make a big deal of stating it's a 4 layer coil on the DS's. Gap size could different for the 2 layer coil and 4 layer. It probably would be. Wire gauge is probably different. Length of wire in the gap??? It's a guess without more information. 

Speaker motor and coil design is a DEEP rabbit hole. 

Car audio drivers have been using 4, 6 and 8 layer coils for years. I've even seen some drivers with 12 and 16 layer winds. 

The short version is that the answer is not as simple as that.

Have you ever done modeling of electromagnetic circuits, or tried to design and model a speaker motor and voice coil system?

The wire material, total length, number of turns, wire gauge, etc...All matter, but that is only part of the puzzle. The gap geometry, amount of wire in the gap, magnet size, shape, grade, steel grade, shape, etc all have an effect. It's a complex set of tradeoff's and compromises. If you modify one thing it affects many others. Copper and aluminum are both useful. Copper becomes very heavy and is more expensive for long xmax, large diameter voice coils like those required for modern sub drivers.

21SW152 is good for both cabs and quite a few others. That driver is a good long term investment.

Can't say I really know much about Psytrance honestly but I assume it is electronically generated...Got a link to some representative music? I don't generally find that type of stuff very "fast" or "sharp" but it's not my usual genre either. Have you ever thrown it into a spectrum analyzer to see where the frequencies you find lacking are?

I prefer to use big beefy mains that can reach the subs well and truly cover the mid bass. Mains with dual 12's or 15's for example . Barring that I like to have a sub that can go up high enough to take the midbass on it's own. Mostly for the reasons that SME posted...Extra crossover, extra amps = more chance for mistakes and more difficult system integration top to bottom. Delay and timing issues etc... I get it though it's easy to turn up the channel for the amp driving the kick bins versus EQing it in.  

There's nothing wrong with a 4 or 5 way system. I've heard them sound good. Just takes a bit more work. Where it always gets me is in cost/weight/size. The extra kick bins often end up quite big and heavy. What if that extra cost/weight/size/power was put into the subs and mains?

Most of the "subs" in the pro arena either have really bad issues above 100Hz or if they are good up to 150Hz or so have no bottom end. You end up with 2 way bass systems. The Skhorn can be run up to about 150-160Hz. It's one of the more brutal bass cabs I've ever heard, including the 80-160Hz octave.  It is expensive and heavy though. I need to get my single driver version done.

I don't know a lot about any of the options you listed. You never see good response measurements or even good simulations of these designs. You see a lot of people recommending and using them that say they are good but how often would people admit what they are using may not be that good? Not saying they are or aren't. I just don't know. I've not heard them except for the Martin 215. It was loud and efficient. A loud 100-300Hz bin is relatively easy.

I'm probably not helping you much but I just don't know much about those proposed kick bins.

I'm keeping an eye out for availability here in the US but no one has them yet.

21 hours ago, m_ms said:

1206 x 608 x 768mm's (H/W/D).

Roughly 47.5x24x30.25". They aren't lightweights that's for sure!

What are the overall outside dimensions of the MW's anyway?

11 hours ago, dgage said:

Second floor apartment?  Really?  When I have people ask about my subs and find out they’re in an apartment or connected condo, I tell them my subs come with eviction notices.

Ugh...2 Microwreckers in a 2nd floor apartment...I hope the downstairs neighbors are VERY understanding.

10 minutes ago, radulescu_paul_mircea said:

Today was the delivery term, but because of the holidays, it will be a small delay. I'll post some pics and my opinion when I get them.

Great... You will be the first person I know that has gotten their hands on these. 

Looks good...

Paul did you get the 21NTLW5000's? There aren't any over here in the US yet. I'm keeping an eye out for it because it's on my short list.

7 hours ago, radulescu_paul_mircea said:

Going back to my issue with the drivers in electrical series, I can say there is absolutely no difference between them linked like that or parallel. All my tests and measurements showed me nothing changes, a small voltage difference is present, but only 1-2 V at 60 V sines. 

That is good news. I'm glad you verified it. 

Yep...I emailed Brian about the SP1-6000 plate amps a few weeks ago and he put me in contact with Justin. Brian says he still does consulting work for SP when needed but otherwise is retired. 

I have heard the TH-50 way back what must've been a decade ago now...It was quite powerful in the basement of the home that we demo'd it in. Ivan also brought a Danley CS-30 and a THspud from what I recall. The TH-50 uses a beastly 15" driver (MTX 9515-44) and it's a huge cab but it does deliver the goods. 

Since the thread is about the Skhorn perhaps we should move discussion to a build thread on the Microwrecker. LilMike is someone I've talked to for years and met before. He's a good guy and he lurks around here, so if you have questions don't hesitate to ask him. 

14 hours ago, SME said:

I would call the SKhorn a horn hybrid as it does behave like a horn in the upper end of its bandwidth and like a vented cabinet in the lower end.  But really, I think obsessing about terminology misses out on the important nuances.

Agreed...There have always been a lot of hang ups with terminology in audio circles and fixation on defining things by a strict set of rules. In order to be an IB the back volume must equal at least 10X VAS...Waveguide vs horn etc...

I consider the Skhorn a hybrid 6th order design.

Fun fact...Skhorn is pronounced like the word scorn and I gave it that name because after exploring all the options I could think of attempting to do a horn of some type, I ended up not doing a horn at all. No matter how much I wanted to, and I really wanted to make a horn at first, I simply could not make a horn this size that would perform like this cab. After giving up and scrapping all the horn ideas for a hybrid 6th order BP I called it Skhorn as a middle finger to bass horns in general. Most people think it's called that because it's some kind of horn LOL.

5 hours ago, m_ms said:

Reading up on this thread one gets the feeling that a "low corner" below some 25-30Hz for subs used for music augmentation - TH's, FLH's and 6th order BP perhaps in particular - may even be inadvisable if the most "musical" and best-integrated sound (with the mains) is sought. Is there any truth to this?

/Mikael

TH's have a harmonic spike in what is commonly considered their bandwidth which can end up causing issues. If the TH is tuned low it moves the placement of this spike down in frequency until it can end up in the critical bandwidth you want to use the sub in. Bass guitar and kick drum range...As the TH becomes more and more undersized it exaggerates the spike in response even more. The more the tuning is lowered the greater the TH will be undersized effectively. There are tricks that can be done with the design to minimize this harmonic spike and a very well damped driver helps somewhat. You can also attempt to address it with EQ. However if it is bad enough it will always be audible. In my opinion TH's work the best when only extending to 25-30Hz at the lowest due to this. This allows you to keep that harmonic above 100Hz and above the usual low pass for the sub. This is why I quit pursuing big TH's that extend deeply.

Other designs can be made to sound excellent over a wider range much easier. Sealed, IB, ported, FLH, or BP variants. In my opinion for HT powerful headroom down to the 15-16Hz range gets most of the content. It's greatly diminishing returns below that point. For music I consider 25-30Hz the minimum for good reproduction without missing out on the "heavy" notes.

18 hours ago, radulescu_paul_mircea said:

A K10 is more powerful and efficient than an FFA10k. On a pair of SKhorns 16A will be enough on the long. But you will see a voltage drop for sure and also you will see lots of amps drawn on the short term. On the K10 and K20 I have I've seen 47 amps at 225 V on display for large peaks. That's on the power supply, not the output stage. There I've seen 100 Amps and 220 V peaks on the K20 meaning 11KVA reactive power. 

To add to this...The K series is set for a maximum draw of 32A slow average from the AC line to avoid tripping breakers. However with music signals this is quite a bit more than this seems. It is easy to pull more current for short durations but averaging even 20A with dynamic content is a LOT of power. I run into this with very long sine wave sweeps but this is not normal use. This is why amplifier current pull is rated at 1/8th or 1/4 duty cycle rather than 100%. The K20 at 1/4 duty cycle into 4 ohm bridged pulls 25A (230v AC).

Hey Mark.

Sure...I pointed out it is a 6th order variant the first time I posted about these a few years ago. Personally I refer to these as BPH's due to the large expanding slot section, where as a traditional vented 6th order would have a chamber and a port. These lack a traditional chamber or vent on one side of the cones but I don't really care what label is put on it. BP6/BPH etc...Results are what matter to me.

22 minutes ago, dgage said:

Mr. Ricci, can you design me a ported box for the SI HS-24 with no more than 8 cu.ft. of enclosure volume?  And can you tune the port to 12Hz please?  You’re the bestest!  Thanks Josh. 

 

Happy Holidays guys!  Thanks for hosting such a magnificent and informative site!

I'm on it Dave!

Looks like this type of design is getting quite popular...Lot's of people working on them or asking about em. If I had a dollar for every time someone asked me to design a cab for them from the ground up...had probably 4 guys ask in the last week.