Going old school

Jump to Latest
#21
augerpro said:
I was actually considering this: https://www.madisoundspeakerstore.com/approx-5-midrange/scanspeak-15m/4624g-discovery-5.25-midrange/

But that FaitalPro is cool too.
Click to expand...
What's interesting about that driver? Higher sensitivity but not demodulation rings to I'd pass. YMMV.

That Faital driver is the single unit in its standard product line with a copper cap...

Misco took great pains to mimic the original 7" midwoofer for the NS10, but apart from being a very good drop in replacement for now discontinued NS10, do you really want this for a original design?
 
#22
profiguy said:
Theres also thr SB34NRX75-6 for sealed cabs and the SB34NRXL75-8 for ported cabs. Both great paper cone woofers which can be used hugher in cutoff than most 12s and sound clean. Both are over 90dB/W sensitive and the NRXL is closer to 93dB/W. Likely the best semi pro woofer for around $300. Very low distortion and has a 3" VC, uncommon for a driver of this type.
Click to expand...
How are these drivers for self noise? Could they be run in an ultra-nearfield open baffle situation?
 
#23
tktran303 said:
What's interesting about that driver? Higher sensitivity but not demodulation rings to I'd pass. YMMV.

That Faital driver is the single unit in its standard product line with a copper cap...

Misco took great pains to mimic the original 7" midwoofer for the NS10, but apart from being a very good drop in replacement for now discontinued NS10, do you really want this for a original design?
Click to expand...

The Discovery line has shorting rings lIRC
 
#27
Augerpro here asking for a midrange and getting recommended 12s SMH. Depending on the budget you can always go pro or go home. The new SB series looks very nice, maybe their mids will work out. The Rosso 6" could be nice, but the Nero 6" is just excessive in all the right ways. I'm sure I don't have to shout about FaitalPro's excellent range of pro drivers. They're good. They're classy. They're prosound.
 
#28
"They're prosound"

That means they prioritise high SPL/power handing/durability above all else.
The show must go on.

But I'm not sure one needs that in a domestic setting?

I'd rather have more smooth and flat response on and off axis response, and 6-10dB lower harmonic and intermodulation distortion, in particularly lower higher order distortion, lack of motor/air noises, And take the 10dB lower sensitivity...

Out of the bass drivers augerpro has shortlisted, I'd think about the desired LF extension and box cabinet dimension requirement and go from there. Twin Deltalite 10 for a slim enclosure. But what exactly is old-skool from 1960-70s? Are we talking about stumpy speakers that sit on the ground who's tweeter point to your chest? Or the ones that sit on a stand eg?

1688706914355.png

https://www.erinsaudiocorner.com/loudspeakers/klh_model_5/

Would love to hear more form factor details or engineering requirements from Brandon.

Exactly how big is "big baffle"

Revel's F328Be has a "50.9" x 13.5 " x 17.6"" baffle, and they squeeze in triple 8" woofers.

When I have 13.5" wide baffle, I squeeze in twin twelves.

Does your friend have an aesthetic preference Brandon?
 
Last edited:
  • Like
Reactions: bedrock602
#29
Just because a driver is designed for pro sound use, doesn't mean they can't be good for hifi. One of the most important pieces of spec is the Rms and Kmr. For a driver to not hide low level detail, it will almost certainly (not always though) have low suspension resistance to movement. Suspension losses are ia huge detriment to low level detail and macro dynamics. For example, many of the lesser Eminence drivers ie, Alpha 12A, Delta 12A, Delta Pro 12A, etc are excellent performers, often exceeding some dedicated hifi drivers. The Kappalite 12LF is another driver like this, despite the neo magnet, has really nice low level detaul retrieval in the midbass, better than many like hifi drivers. Id rate it as good as the Peerless NE315W - one of the best sealed box 12s I've heard to date.
 
  • Like
Reactions: deanznz
#30
Yep. Lots of different factors come into play. Low Xmax will also help keep inductance (and the associated modulation) low, so a 12" 'pro' mid-woofer with 4-5mm Xmax will likely have a much clearer mid-range (~1 kHz) than a 12" 'hifi' woofer/sub with a 10mm Xmax. The caveat being that if bass levels are indeed pushed to high levels, mid-range clarity goes out the window.

A +/-3mm ceiling is about as much as I realistically ever need these days, and that's stereo 10". Lavoce for instance has base model drivers with voice coils starting at 1.5-2" diameter and 12-13mm length. So even if they specify 200+W, realistically it'll be more like an actual 20W of continuous heating. And for sound reinforcement the sub-bass would probably be filtered out anyway.

Most of my box sims show high sensitivity 12” drivers plateauing at about 1mm of cone excursion @ 1W in sealed boxes, so for <4mm that indicates a power limit around 16W.
 
#38
profiguy said:
Just because a driver is designed for pro sound use, doesn't mean they can't be good for hifi. One of the most important pieces of spec is the Rms and Kmr. For a driver to not hide low level detail, it will almost certainly (not always though) have low suspension resistance to movement. Suspension losses are ia huge detriment to low level detail and macro dynamics. For example, many of the lesser Eminence drivers ie, Alpha 12A, Delta 12A, Delta Pro 12A, etc are excellent performers, often exceeding some dedicated hifi drivers. The Kappalite 12LF is another driver like this, despite the neo magnet, has really nice low level detaul retrieval in the midbass, better than many like hifi drivers. Id rate it as good as the Peerless NE315W - one of the best sealed box 12s I've heard to date.
Click to expand...

Re: One of the most important pieces of spec is the Rms and Kms. For a driver to not hide low level detail, it will almost certainly (not always though) have low suspension resistance to movement. Suspension losses are ia huge detriment to low level detail and macro dynamics.

Is there good data to support this? I'd like to learn more.

From my understanding, the work of Klippel et. al have clarified that Kms is not a fixed number.
It is more accurately Kms(x)- mechanical stiffness of driver suspension as a function of displacement.
And since
{\displaystyle C_{\rm {ms}}}
is the inverse of Kms, it follows too that Cms is better characterised as
{\displaystyle C_{\rm {ms}}}
(x)- mechanical compliance of driver suspension as a function of displacement.
Intuitively we have probably known this to to be true for a long time, since Cms is a small signal parameter; measured at low signal levels (typically fractions of a volt), near the resonance frequency.

As you are aware- the
{\displaystyle R_{\rm {ms}}}
– the mechanical resistance of the driver's suspension (i.e., 'lossiness') is related.

and since
{\displaystyle Q_{\rm {ms}}={\frac {2\pi \cdot f_{\rm {s}}\cdot M_{\rm {ms}}}{R_{\rm {ms}}}}={\frac {1}{R_{\rm {ms}}}}{\sqrt {\frac {M_{\rm {ms}}}{C_{\rm {ms}}}}}}


then it follows that Qms is also better understood as Qm(s) - dependent on excursion.

Now none of this is surprising, because many people have been saying (?complaining) for decades that their measured Qts, Qes, Qmst's can vary quite widely from the quoted spec. Turns out the drive level affects your T/S parameter measurement.

I suspect that micro dynamics is related to what is happening at low volumes/low excursion eg. 1mm or less, and high SPL volumes/high excursion (eg. x-max /2 < excursion < x-max) respectively, and NOT something easily determined by looking at (static) frequency response measurements alone.

The Peerless NE315W was tested by Voice Coil in July 2010 IIRC, but I can't recall how well it performed on the Klippel, nor the appearance of the Kms(x) graph.

The manufacturer's specified Qms of 15 IS high, relativeto other woofers. The flatness and symmetry of the Kms (x) curve flatness may also be related to it's perceived acoustic behaviour.

I may try it investigate this driver before it is NLA. Did you have the 8ohm or 4 ohm variety? How big was your sealed box?
 
Last edited:
  • Like
Reactions: ScottG
You must log in or register to reply here.
Top Bottom