Very similar for THs, just more thermal risks due to more impedance minima and cone excursion minima.
Oof. November is around the corner, and LN16S400 with LN19S450 still unavailable make me crazy.
Lately I was digging into drivers overexcursion modes, and found out that even the stiff 18DS115 with fairly longer coil was flying at average excursion of 20mm one way, peaking at 25mm in B&C Speakers LSI/Klippel measurement. Not even thinking using it that way, but maybe, 15mm one way RMS peaks might not be that harmful for such driver. Also it doesn't add up with the Bl curve with such long coil. It looks those measurements (along with Kms) are not perfectly isolated. Almost all coil in the gap should not cause 50% Bl drop. A lot to learn, still...
The LN19S450 Bl figure doesn't add up in Hornresp. Can't properly simulate I put paws on the physical driver.
Lately I was digging into drivers overexcursion modes, and found out that even the stiff 18DS115 with fairly longer coil was flying at average excursion of 20mm one way, peaking at 25mm in B&C Speakers LSI/Klippel measurement. Not even thinking using it that way, but maybe, 15mm one way RMS peaks might not be that harmful for such driver. Also it doesn't add up with the Bl curve with such long coil. It looks those measurements (along with Kms) are not perfectly isolated. Almost all coil in the gap should not cause 50% Bl drop. A lot to learn, still...
The LN19S450 Bl figure doesn't add up in Hornresp. Can't properly simulate I put paws on the physical driver.
Maybe the specs are off, and since you cant get a physical unit to test with DATS you cant tell the actual TS parameters, mmm... do you think is RCF marketing gimmick to ramp up the prices... or they cant make enough units to satisfy the marketshare ??
It's weird, because RCF had their TS parameters consistently right with their physical drivers. I might be looking into deviations too much, but it is a first mistake in long time. Hope the company is aight. This time RCF failed the release on all levels. Info and showcase bad, specs off, product unavailable. Communication bad. They do not respond most of the time if ever. Grrrr!
The preliminary prices seem to be quite good, and LN19S400 already selling at TLHP supports that. So I guess there is a supply issue.
I wonder, what is with these "Euro drivers". I mean almost same coil specs, almost same motor specs/T&S across the board, from B&C, RCF, Eminence, Celestion, Precision Devices, possibly others, while noone here does 5"+ or 6" voice coils on an 18" driver. There is this "same driver" going through the companies for 10 years now, and there is no excitement about stuff anymore. Yes, Eighteensound has this NTLW series, but that's just one odd, and very pricey in Europe.
The preliminary prices seem to be quite good, and LN19S400 already selling at TLHP supports that. So I guess there is a supply issue.
I wonder, what is with these "Euro drivers". I mean almost same coil specs, almost same motor specs/T&S across the board, from B&C, RCF, Eminence, Celestion, Precision Devices, possibly others, while noone here does 5"+ or 6" voice coils on an 18" driver. There is this "same driver" going through the companies for 10 years now, and there is no excitement about stuff anymore. Yes, Eighteensound has this NTLW series, but that's just one odd, and very pricey in Europe.
Maybe they are ....delaying the new stuff for years, that way they hijack the prices and still give us old driver tech, instead of coming up with novelty materials and designs.
It's a crazy world
It's a crazy world
That would be globally another good topic. Milking the current technology because enough money is still pouring in.
@noviygera
Fair driver, but way outside requirements.
Normally , a port velocity below 25 is ok, more than that and you are in chuffing noise land , if the port is flared it is less prone to make noises.
In conventional design, indeed it does. In the particular design I am "honing" though, different approach is chosen, and High pass filter with EQ is setup in such a way, that the port only assists the system with excursion and impedance, but is not really relied on regarding production of sound pressure. It does some, but not the majority. It is cut off above its tuning frequency, for high SPL uses, so it has way less work to do. Therefore less air flow, and very low risk of chiffing. Also working outside the set range, there is less SPL port compression, so the system loses less SPL via port losses.
I thought we agreed in either the TL or Hornresp thread that <17m/s was the goal?
Over on avsforum.com, they accept <25m/s.
That’s a really interesting approach and it’s one step ahead of what I was planning on trying. I am interested in building a prototype for myself. What do you think should be the port size for an 18 inch high excursion woofer?
Also, are you going with round ports or slot ports?
I’m excited to build this thing!
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@noviygera
As almost no manufacturer planned to use the speaker design exactly this way (though close, similar approaches), Cone excursion, port contribution and power draw behavior have to be balanced.
Most medium high-end drivers are barely qualifying for borderline displacement capabilities. The RCF LN series is about the first affordable design that can truly do that. Older models either could do it only in larger box volumes, would be strained, or needed to be 21" size with great Xmax capabilities.
Depending on the box size, tuning and used range, I think that ports for this 18" design should be around 350-450sq centimeters. That's not little already. But it wouldn't be sufficient for conventional use with Xmax of 18mm, if not even 20mm at all.
I'm going with slot ports with slightly opening shape and flared, so I might reap another dB of sensitivity/efficiency from horn effect in the upper band. Mind you, my design is not supposed to be louder, regarding driver potential exploitation. It is supposed to be just very dense. It will almost/about keep up, in just significantly smaller package that combined with poplar plywood, might be one-mannned box, not needing wheels for transportation. A box that is rather heard than seen.
As almost no manufacturer planned to use the speaker design exactly this way (though close, similar approaches), Cone excursion, port contribution and power draw behavior have to be balanced.
Most medium high-end drivers are barely qualifying for borderline displacement capabilities. The RCF LN series is about the first affordable design that can truly do that. Older models either could do it only in larger box volumes, would be strained, or needed to be 21" size with great Xmax capabilities.
Depending on the box size, tuning and used range, I think that ports for this 18" design should be around 350-450sq centimeters. That's not little already. But it wouldn't be sufficient for conventional use with Xmax of 18mm, if not even 20mm at all.
I'm going with slot ports with slightly opening shape and flared, so I might reap another dB of sensitivity/efficiency from horn effect in the upper band. Mind you, my design is not supposed to be louder, regarding driver potential exploitation. It is supposed to be just very dense. It will almost/about keep up, in just significantly smaller package that combined with poplar plywood, might be one-mannned box, not needing wheels for transportation. A box that is rather heard than seen.
So, it seems I will not be able to get my paws on the LN19S450 this year, stuff gets delayed again and again by RCF.
I might borrow or buy one, but the project with these is completely called off already.
Back to the 21" madness. Either LaVoce San215.30 or Precision Devices PD.2160-1N (if they send me large signal data) it is.
I might borrow or buy one, but the project with these is completely called off already.
Back to the 21" madness. Either LaVoce San215.30 or Precision Devices PD.2160-1N (if they send me large signal data) it is.
So, another day in my echochamber.
Finally decided that B&C speakers 18DS115 cannot do the job due to the excursion requirements. It is not as stiff as previously thought of, but given the stiffness variation in excursion, it would probably generate too much distortion.
The San215.30 was sold before my eyes from TLHP, with expected leadtime of 18 weeks.
The Precision Devices PD.2160-1N is very expensive and noone responded on request for large signal data, even small piece I need. It seems the stiff suspension would somewhat hold it back for my purposes, when even the cheap LaVoce SAN214.50 approaches its performance in the sims very much.
Full setup will be postponed anyways for family issues.
But I said F it, life is not that short, and ordered the LN19S450 at local shop in hope. A man can dream. Hopefully I will not have to print the image of it, put it into envelope and put the envelope under the christmas tree.
Though I AM going very extreme on this one, and will fight to put it into 90-95l net enclosure with 26Hz tuning for mixed/PA use. Very brave design.
Finally decided that B&C speakers 18DS115 cannot do the job due to the excursion requirements. It is not as stiff as previously thought of, but given the stiffness variation in excursion, it would probably generate too much distortion.
The San215.30 was sold before my eyes from TLHP, with expected leadtime of 18 weeks.
The Precision Devices PD.2160-1N is very expensive and noone responded on request for large signal data, even small piece I need. It seems the stiff suspension would somewhat hold it back for my purposes, when even the cheap LaVoce SAN214.50 approaches its performance in the sims very much.
Full setup will be postponed anyways for family issues.
But I said F it, life is not that short, and ordered the LN19S450 at local shop in hope. A man can dream. Hopefully I will not have to print the image of it, put it into envelope and put the envelope under the christmas tree.
Though I AM going very extreme on this one, and will fight to put it into 90-95l net enclosure with 26Hz tuning for mixed/PA use. Very brave design.