Low Down Sound 15/6.5 Cab

[rpsands]

I spent some time chording on this thing and I think that is where the flat crossover (I turned the attenuator to noon, which is -3db or so, so flat with the 3015LF) really comes into play. Chords sound AMAZING on this cabinet. I played the little part from Scar Tissue where the bass chords during the solo and the sound difference from the 8MRA to the 6nd410 is literally ridiculously obvious.

The higher strings really, really stand out - even though they're quieter due to my bass's setup, they just don't seem to get caught in the MUD of the 3015LF when chorded with lower strings.

It sounds great right up to the higher B chord (E-string 7th fret) before it starts to sound weird due to the low note.

Also, slap and pop sounds great even with no horn, imho. I could see having a little sizzle being nice, but the popped strings really zing out of that mid driver.

I'm gonna hook up the distortion pedal next

 

[coolrunner989]

This has been a great read, along with the continuing fEarful threads. One of these designs seems to be the end-all cab for me. So first I have to say thanks to everyone who has contributed to the design of these cabs and all of those who have posted their own reviews for further refininment of these cabs.

As it says in my sig, I use two Dr. Bass cabs right now, a 1580 (15+8+tweeter) and a 15. The 15 is 4 ohms and the 1580 is 8. I also had a 4ohm 2460 (2x12 +6+ tweeter) earlier that was great except for the low end output was a little shy for my tastes. Anyway, I think a few people in this thread that have played with these LDS cabs have also had one or both Dr. Bass cabs, could anyone shed some light on the comparison tonally and volume wise? Would I be able to get a fEarful style cab at 8 ohms that would compete SPL-wise with my stack? I crank my Shuttle Max to noon or more with my band (no PA for rehersal, half our gigs have PA and half dont) but with the mixed ohmage its kind of tricky to figure out. Thanks!

 

[rpsands]

I have a Dr. Bass 3080 which is very fEarfulesque.

The bottom line is Marc uses a higher crossover than I'd like, and a lower quality mid driver, and less internal space for the 3015LF (so less low end).

I think with a shuttlemax you would be better off with a pair of 12/6s or 15/6s - you want two 4 ohm cabs ideally but two 8 ohms would be OK (375w/cab).

Bottom line I can say that these cabs really want lots of power. This cab took all 500w @ 8 ohms of my Iamp and wanted more. It gets really, really loud, but it's quieter than the 3080 (which is 4 ohms with twice the drivers of course, two 3015LFs).

I'd say it will be louder than your 1580 by itself, with more even mids, but not as loud as both. The 1580 with a 3015LF (if yours has one) is going to be very close in volume, but slightly less (1db or so ) due to the interior volume difference, and not as sensitive in the low lows.

 

[greenboy]

The lowest "usable frequency" for both cabs is 40 Hz according to Eminence.

The "usable frequency response" spec on driver datasheets is basically one of several useless piece of non-information; it doesn't reflect how different two driver models can actually be and share one or both of the numbers. It's for box stuffers and tire kickers.

I've had 3015 and 3015LF in a variety of box sizes and tunings. In three-way or with a mid driver, as a generality the 3015LF sounds more authorative and reaches deeper, and when driven hard continues to sound clean and mean. It reaches deeper too. As you increase low end content especially with a lower tuned bass or synth it becomes apparent how much more it gives without flinching, never getting boomy or sounding shy.

 

[thudfromafar]

A few questions...

1) The woofer is rated at "450 watts" but the pros have been saying how it can handle 1000+ watts just fine. I am familiar with x-max and thermal max, but how can the driver far exceed thermal max and still be fine?

2) How much would a fearful-type cab cost from LDS? Ideally I was interested in the barefaced but with currency conversion and shipping that is less likely. If this needs to be said over PM that is okay too.

3) More recommendations for 1000 watt amps @ 8 ohms?

I am genuinely interested in these types of innovations. I have read thru basically every similar 15/6 thread on talkbass (not saying I've retained it all).

 

[rpsands]

Call Don and ask. My last name should be obvious but feel free to refer to my cabinet as it's the only one with the fEarful form factor to my knowledge.

 

[KJung]

The "usable frequency response" spec on driver datasheets is basically one of several useless piece of non-information; it doesn't reflect how different two driver models can actually be and share one or both of the numbers. It's for box stuffers and tire kickers.

I've had 3015 and 3015LF in a variety of box sizes and tunings. In three-way or with a mid driver, as a generality the 3015LF sounds more authorative and reaches deeper, and when driven hard continues to sound clean and mean. It reaches deeper too. As you increase low end content especially with a lower tuned bass or synth it becomes apparent how much more it gives without flinching, never getting boomy or sounding shy.

+! I have a feeling that with my little piss-ant 300 watts and the fact that I don't crank the low end, the 3015 and 3015LF would probably sound (just guessing) pretty much identical in a moderate volume, small room listening test (like we did with the two cabs featured in this thread).

They again sounded darn good (regardless of the actual driver model...same or different across the two cabs?!?), and it sounds like with the LF drivers (again, we don't know absolutely for sure what driver Chef has in his cab), that tone I heard with my low wattage, moderate volume 'test' would stay even and get even bigger with big watts at high volume.

If that's the case, this design is a BIG winner with that LF speaker.

Nice job again on this whole concept!

If I can muster up the balls to plunk down the cash on a Puma1000 (which seems the only micro head capable of doing this design real justice at 8ohms... i.e., 1000 watts bridged at 8ohms), I'm going to get one of these in a three way design. I already know the TecAmp Puma voicing sounds GREAT with these cabs, but the 500 I have just doesn't have the wump at 8ohms to really get it up to full (or even close to full) performance.

 

[rpsands]

I am starting to really gas for the Puma 1000 The Iamp is just barely enough to push this thing.

It'd be spiffy if those guys made a preamp too but I guess it'd be damned expensive. 1500 bucks is just not gonna happen for me for a head.

 

[greenboy]

+! I have a feeling that with my little piss-ant 300 watts and the fact that I don't crank the low end, the 3015 and 3015LF would probably sound (just guessing) pretty much identical in a moderate volume, small room listening test (like we did with the two cabs featured in this thread).

Largely so, until you actually hear both of them during the same time period. The 3015 is actually a great bass driver in a two- or three-way if you don't play below E or the occasional drop-D. The box can be a bit smaller (and tuned higher) then and the differences between the two in their suitable enclosures are very subtle indeed until as you say get into bigger power.

I read the Puma1000 manual today. Looks like a real good reccomendation for a mini when taken with what you've said about the Puma500.

 

[Ryan Mohr]

Largely so, until you actually hear both of them during the same time period. The 3015 is actually a great bass driver in a two- or three-way if you don't play below E or the occasional drop-D. The box can be a bit smaller (and tuned higher) then and the differences between the two in their suitable enclosures are very subtle indeed until as you say get into bigger power.

This is why I have chosen for Don to build me a one-way cabinet with just a single 3015. I like a vintage tone, so I don't need anything past 4 kHz. Like you said the box, can be smaller, mine is gonna be 3.0 cubic feet, and it will be only 28 lbs according to Don. I'm still interested in the 3015LF/6ND410 in the future for a different tone.

 

[rpsands]

The 28lb 3015 is probably the best cabinet I could fathom for a 4-string bass player who doesn't need slappies. Seriously an amazing ultralight.

The 3012HO in a similar config, crossed over low to an XD125 is really, really exciting to me for a full range ultralight. I think you could get it in at around 22lbs.

 

[Ryan Mohr]

The 28lb 3015 is probably the best cabinet I could fathom for a 4-string bass player who doesn't need slappies. Seriously an amazing ultralight.

Yeah I'm guessing 28 lbs. Don said 26-28 lbs, but the Barefaced Compact is the same design and is 32 lbs.

I'm strictly 4-string, fingerstyle and pickstyle. I'm really looking forward to this cab.

Sorry for the slight derail.

 

[DukeLeJeune]

The woofer is rated at "450 watts" but the pros have been saying how it can handle 1000+ watts just fine. I am familiar with x-max and thermal max, but how can the driver far exceed thermal max and still be fine?

The missing piece of the puzzle is something called "crest factor".

Crest factor is the peak-to-average ratio. Let's assume the peaks are 10 dB louder than the average level, which means the peaks draw 10 times as much power. So even if we have a really beefy 1000 watt RMS amp which can deliver 2000 watts on instantaneous peaks, the average level is still going to be down around 200 RMS watts which is well within the thermal limits of the driver. More likely to be an issue is the excursion demands of that 2000 watt peak.

In practice I would think that it's not uncommon for the peak-to-average ratio on bass to be more like 13 to 16 dB, in which case the peak power would be 20 to 40 times greater than the average. I welcome correction on any of my assumptions here.

 

[billfitzmaurice]

how can the driver far exceed thermal max and still be fine?

Other than for very short duration peaks, it can't. Many may be driving Kappalites with amps rated for far more than 450 watts, but they're not driving them to full output. If they were magic smoke would be the result. Those who think that just because they have a 1,000 watt amp that they're actually putting 1,000 watts into a Kappalite are mistaken.

 

[Chef]

exactly.
sure, i run my wt800b, bridged, into mine, which is ~1200 watts.
but, my eq is flat, the amp ain't truned all the way up, and i'm an easy player.
i like big headroom for the dynamic response it gives me.
i'd be surprised if i was using 1/3 of what power was available.

 

[Chef]

update:
mine has just 2-3 ribs on the outside, not lotsa ribs.
so, LF for me, I reckon.

 

[thudfromafar]

The missing piece of the puzzle is something called "crest factor".

Crest factor is the peak-to-average ratio. Let's assume the peaks are 10 dB louder than the average level, which means the peaks draw 10 times as much power. So even if we have a really beefy 1000 watt RMS amp which can deliver 2000 watts on instantaneous peaks, the average level is still going to be down around 200 RMS watts which is well within the thermal limits of the driver. More likely to be an issue is the excursion demands of that 2000 watt peak.

In practice I would think that it's not uncommon for the peak-to-average ratio on bass to be more like 13 to 16 dB, in which case the peak power would be 20 to 40 times greater than the average. I welcome correction on any of my assumptions here.

Other than for very short duration peaks, it can't. Many may be driving Kappalites with amps rated for far more than 450 watts, but they're not driving them to full output. If they were magic smoke would be the result. Those who think that just because they have a 1,000 watt amp that they're actually putting 1,000 watts into a Kappalite are mistaken.

Okay so there's just a much bigger "safe zone" with this driver than with others? Am I right in thinking this is because it's generally worse to exceed xmax than the thermal limit (in peaks)?

 

[rpsands]

Hey guys,

Please disregard my playing here, I did all sorts of ridiculous stuff for the sake of tones. I recorded this 45 degrees off axis with my Zoom H2 from about 8-10 feet away. I left lots of nasty finger noise in to demonstrate the mids, as I played the major scale up and down each string. No effects/compression other than the MXR M80 for distortion.

Notice the ridiculous solo at the end in I don't know minor lug-style

Next time I'll play some chords and slaps for more fun.

Note the beefy bottom even with the distortion absolutely cranked.

http://63.134.202.170/audio/fearful-tones.mp3

Enjoys.

 

[Passinwind]

Hey guys,

Please disregard my playing here, I did all sorts of ridiculous stuff for the sake of tones. I recorded this 45 degrees off axis with my Zoom H2 from about 8-10 feet away. I left lots of nasty finger noise in to demonstrate the mids, as I played the major scale up and down each string. No effects/compression other than the MXR M80 for distortion.

Notice the ridiculous solo at the end in I don't know minor lug-style

Next time I'll play some chords and slaps for more fun.

Note the beefy bottom even with the distortion absolutely cranked.

http://63.134.202.170/audio/fearful-tones.mp3

Enjoys.

Cool, let's hear more!

That inspired me to post this fEarful 12/6 recording. This was recorded with my interim crossover, not the final design I eventually settled on. I'm playing my EUB, so it's a much different vibe than your clip.

 

[Blues Cat]

Wow the distortion sounds awesome rp.