Bill Fitzmaurice

[quote name='Mr. Foxen' post='714033' date='Jan 15 2010, 12:14 PM']What about them?

There are factors other than driver diameter at play.

They don't sound good because there are 10s and 12s,, they sound good because they are designed taking all the factors into account (or at least getting them right inadvertently).[/quote]
[quote]I asked TC about their cab matching, and they said all their artists bar a few chose the 210/212 because it just works. They designed them to work how they do[/quote]

I seriously doubt that. They look to be reasonably well designed and constructed, but no more so than cabs from a few dozen other companies building bass reflex cabs loaded with Eminence drivers.

There is one fact of audio physics that's never mentioned by any manufacturer: virtually any two cabs together will sound better than either alone. So while the TC 210s and 212s might sound OK together so will most of the 210s and 212s from any other manufacturer. The pertinent question is whether paired TC 210s or 212s would sound better than one of each. That one can only determine by trying all three permutations side by side.

On a side topic the TC 2x cabs do place the drivers vertically, and that is infinitely better than side by side, so that much they got right. But they have a traditional 4x10 in the line up as well, so they're not above sacrificing engineering concerns to the gods of marketing.

[quote name='Al Heeley' post='713969' date='Jan 15 2010, 11:25 AM']If thats the case then why do all the major companies sell same impedance 410's, 210's and 115's, designed to be used in pairs?[/quote]Your question is its own answer. Cab companies build and promote what they think will sell, and the vast majority of players buy their cabs based not upon the engineering within but rather on how they look and who uses them.
Mixing drivers to cover the same bandwidth is not good engineering, but it is successful marketing. If you must succumb to the lures of that marketing a 1x15 and 2x10 are a reasonably good match. A 1x15 and 4x10 isn't.
[quote]Some cabs are made so that they can be mixed, with time aligned, phase coherant and excursion matched cabs, but probably not many.[/quote]I'm not aware of any. If any of the usual sources possessed the technical know-how to do that you can rest assured that they wouldn't keep it a secret. AccuGroove tries to make it seem that way in their ad copy, but their level of technical incompetence was tellingly revealed in the AccuSwitch debacle.
The only significant engineering that I'm aware of where mixed cabs is concerned lies in making the footprints the same for stacking. More than a few 1x15 and 4x10 cabs share not only the same footprint but the exact same cabinet save the number of holes in the baffle. That should set off alarm bells, but curiously it doesn't. The stacking of the two looks very pretty, so it sells.

[quote name='Phaedrus' post='711114' date='Jan 13 2010, 06:43 AM']I can't escape the concern that stuff will shake loose inside - does this happen?[/quote]
Only if it gets away from you on a steep hill.

[quote name='BottomEndian' post='710130' date='Jan 12 2010, 11:00 AM']Oh yeah. Of course. I'm even more confused about the noise now then. :wacko:

EDIT: No, wait. It's still got a switching power supply, so is it possible that the power supply kind of "runs down" its clock speed as it powers down, thus creating a falling-frequency noise?[/quote]I've heard that with many amps, it's just an artifact of the supply caps discharging.

[quote name='Beedster' post='708480' date='Jan 11 2010, 03:07 AM']I received a brief reply...confirming that the noise is usual on this model.[/quote]Odd that it doesn't say so in their ad copy.

[quote name='AlanP2008' post='707552' date='Jan 10 2010, 07:15 AM']Re Xmax/Xlim: My understanding is that if you exceed Xmax, distortion will exceed some arbitrary value that the manufacturer uses to establish Xmax, whereas exceeding Xlim is likely to result in damage.[/quote]There's nothing arbitrary about xmax, it's when distortion reaches 10%. Some manufacturers still use the old coil depth versus plate thickness method, and that is arbitrary and obsolete. Xmax tells you the maximum safe power level that may be applied, and it's what you consider if you have a limiter that allows restricting power amp output, though that's more of a PA scenario. Exceed xlim and the driver is damaged, irreparably so, so it's not something you want to even vaguely flirt with.
[quote]I had a trace 2x10 with horn,uprated to 400w neo style,yes more responsive but didnt seem to handle the full range,[/quote]All that indicates is that you used the wrong ones. You can't just drop any driver into a cab willy nilly and expect a good result. A very fair amount of research is necessary, as this thread reveals.

[quote name='AlanP2008' post='707220' date='Jan 9 2010, 06:14 PM']The best thing I found, was in trying a single Eminence Delta 12 LFA - a single 12", and it seems much better than a Deltalite 2512...

It's Resonance is pretty low at 51Hz, and also being a single speaker in the cab gives an excellent bass response, but mainly, it has a massive Xlim at 13.5mm, which allows a lot of power to be used even with bottom strings. Ok, Xmax isn't so high, but it is good at 4.8mm. I know there is likely to be increased distortion if this is exceeded, but at least it won't be trashing the voicecoil...[/quote]Try the 3012HO. Xlim is moot, xmax is everything. The D12LF was state of the art ten years ago, rendered obsolete by the 3012HO, which is also a contender but really needs to be used with a six ought five midrange.

[quote name='Beedster' post='705390' date='Jan 8 2010, 07:51 AM']according to PJB, without the hissing/whistling noise as the result of musing a different class amplifier

C[/quote]I hope PJB knows the difference between amplifier classes, and that noise is not an inherent quality of Class D. Noise can be a problem with switching power supplies, and switching supplies are often employed with Class D amps, but having the one doesn't always mean having the other.
In any event, with the recent flooding of the market with micro amps one doesn't have to look to only one source. I'd be looking at alternatives other than just a more expensive one from the same source.

[quote name='Beedster' post='704167' date='Jan 7 2010, 08:59 AM'], he's now come back to me reporting a phone conversation with Phil Jones himself, in which it was determined that the noise is normal for the Flightcase and for Class D amplifiers generally (which is apparently why I don't get similar noise problems with other, larger, amps).
Am I being fed some BS here, or should I just accept the noise as perhaps the only limitation of an otherwise pretty good piece of kit?
Thanks
Chris[/quote]
BS. It's probably clock noise from the power supply, which has nothing to do with Class D, and everything to do with a defect in the amp. I hope it's not normal to the amp, as that would indicate a flaw in the amp design.

[quote name='chris_pokkuri' post='701345' date='Jan 5 2010, 05:36 AM']Hi all, happy new year!

I'm planning on getting some effects soon. Just wondering what your opinions are on whether there is a better speaker size and configuration to use with distorted/overdriven bass?

Cheers,
Chris.[/quote]
Effects do nothing below 100 Hz while they can destroy tweeters in a heartbeat. The best way to do it is to run a separate small guitar combo amp above the bass rig and run the effects through it only.

[quote name='pantherairsoft' post='483676' date='May 9 2009, 07:26 AM']WHich seems stupid as Ashdown seem to only make 8Ohm cabs, menaing they make nothing perfect for the Little Giant head... hardly a strong marketing idea![/quote]
Get 8 ohm cabs. Each power amp is quite capable of driving an 8 ohm 1x12, 1x15 or 2x10 to full output, and if that's not enough you could use as many as four 8 ohm cabs total. 'Getting all the watts out' with only one cab per channel is a shortsighted view, unless the cabs in question are 4x10s.

[quote name='AlanP2008' post='700532' date='Jan 4 2010, 10:17 AM']2510: Resonance 53Hz, Usable Frequency Range 60Hz-4kHz, Sensitivity 97.3
2512: Resonance 42Hz, Usable Frequency Range 54Hz-3.7kHz, Sensitivity 99.9
2515: Resonance 42Hz, Usable Frequency Range 54Hz-3.7kHz, Sensitivity 99.2
Basslite S2010: Resonance 46Hz, Usable Frequency Range 54Hz-4kHz, Sensitivity 96.2

Thanks again
Alan[/quote]These specs in and of themselves reveal almost nothing about how the drivers work when loaded in a cabinet. That can only be determined using all the driver T/S parameters with speaker enclosure modeling software like WinISD Alpha Pro for the region of pistonic function, roughly up to 200 Hz, and the SPL charts from the manufacturer driver data sheets for above 200 Hz. And then there's the matter of being able to interpret the results.
BTW, if one only had the above data as predictors the differences between the four drivers listed would be, for all practical purposes, inaudible.

[quote name='AlanP2008' post='700376' date='Jan 4 2010, 07:39 AM']... I've come to the view that, as someone with an electronic engineering background, and in the distant past an audio engineering background, if I were designing a bass cabinet today, I wouldn't even consider 10" drivers -- 12" would be the minimum, for all sorts of reasons (resonant frequency and useful frequency range being just two of them...)[/quote]
If you investigate further you'll find the differences between tens, twelves and fifteens in general are slight, while those between specific models of drivers are considerable. You'd also find that the 2x10 is, all things considered, the most versatile configuration when the drivers are vertically aligned (and most are not) while the 4x10 is the most intrinsically flawed.
Where tens are concerned my preference lies with the Eminence Basslite S2010 and Deltalite II 2510.

[quote name='umcoo' post='699668' date='Jan 3 2010, 11:38 AM']I'm looking for a flight case for my 135 and castle cases do one for the bassman 100. I measured the 135 and the case and the case seems a really tight fit. Is that how they're supposed to be? Help me spend money folks![/quote]
Check for yourself here:
[url="http://www.ampwares.com/"]http://www.ampwares.com/[/url]

[quote name='gnasher1993' post='698816' date='Jan 2 2010, 11:37 AM']So what are the likely stats of that cab?[/quote]98dB/1 watt sensitivity is possible, with a -3dB reading at 45 to 50 Hz. But at 20 Hz it's likely only capable of 70dB/1 watt, with a maximum output at 20 Hz of only 80 to 85dB. 80 to 85dB at 20 Hz is inaudible.


[quote]I tried one a few weeks ago and it sounded great, definitely at the top of my list to buy. I don't need frequency response that low so it doesn't matter, it's the sound I want.[/quote]
No one needs response that low, and no one sells a bass cab capable of it, so it's silly to lie about having that capability. But that's what marketeers do.
Truly useful information would be an SPL chart, polar plots and displacement limited power ratings, SOP in the high end PA world where the customer tends to be very knowledgeable about these things. But I guess if you're not paying upwards of two thousand quid per cabinet you're assumed by the manufacturers to be a rube who'll believe whatever they lay out there.

[quote name='gnasher1993' post='698745' date='Jan 2 2010, 09:27 AM']The Hartke Hydrive 1x15" has a great frequency response all the way down to 20 Hz.[/quote]Only in the fantasy world of marketing department schlockmeisters. In the real world the physics of how loudspeakers work render the claims of [i] Frequency Response: 20 Hz to 17 kHz
Sensitivity: 98 dB @ 1 W/1 m[/i] totally beyond the realm of possibility.
If you could package up all of the bullcrap contained in the Hartke webpage description of the HX 115 you could fertilize a goodly sized farm with it.

[quote name='absentmindeduk' post='698513' date='Jan 1 2010, 08:34 PM']I added the 115.
The sound is definately more rounded and punchy at louder volumes.[/quote]Undoubtably. Virtually any two cabs together will sound considerably better than either one alone.
There are instances where a specific 1x15 will have better low end capability than a specific 2x10. Unfortunately there's no way of predicting when that will be the case. One can, however, be assured that a pair of identical 2x10s will work well together, and far better than just one. If one doesn't have the opportunity to try both options side by side adding the additional 2x10 is the more prudent move.

[quote name='chris_b' post='697985' date='Jan 1 2010, 09:46 AM']Good 10's can handle a low B better than most 15's these days. I would add another 210 rather than a 115. Also I would roll off the Gain a little and get your volume by adding a little on the Master volume.[/quote]+1. The size of the driver has precious little to do with how low it will go, that's the product of many factors, not the least of them being the physical size of the cabinet.

[quote name='Bloodaxe' post='697513' date='Dec 31 2009, 02:38 PM']Usually fine, but best to avoid the North Atlantic in the iceberg season.[/quote]Only if you're on the White Star line. No problem on a Carnival Cruise. They can use the extra ice for the drinks.

Is there an FAQ section here? This same question pops up on at least a bi-weekly basis.

[quote name='chris_b' post='694796' date='Dec 28 2009, 07:33 AM']How loud is loud? I don't like combos and would always go for a separate amp and several cabs. I think it's more flexible, you get more for your money and you can upgrade more easily.[/quote]+1. Combos are made to be convenient, and to keep the overall size, weight and cost down they usually compromise on the quality of the speakers. Even if the drivers are of decent quality when the cab is too small they just won't work well.

[quote name='fergy1971' post='694045' date='Dec 26 2009, 06:45 PM']what would be the main issues?[/quote]Instead of your drummer sounding bad both you and he would sound bad. Leave it at that.
On this side of the pond if you're not playing the best rooms it's expected you will provide your own PA. If you don't have one you'll never graduate to the rooms where you won't need it.

[quote name='Adrenochrome' post='693975' date='Dec 26 2009, 04:09 PM']Actually I can see more probs than I could write down.
Put him through the PA![/quote]+1. There are a dozen downsides to putting drums through your rig and no upsides.

[quote name='Mr. Foxen' post='686219' date='Dec 16 2009, 07:20 AM']You can break a 300w rated speaker with 200w, if that 200w is low enough to drive it past excursion limit.[/quote]
Not likely, you must exceed xlim to cause damage, not xmax. But an amp rated 200w at 1% THD may hit 400w at 10% THD, and that could exceed both xlim and Pe.
[quote]In amp rating, both Traynor and Ampeg measured the out put just before clipping to get the RMS, Max is the maximum the amp will put out.[/quote]Amps are measured at a specific THD percentage, using Root Mean Square voltage. Clipping is not part of the equation.

[quote]In speakers it is pretty much the same RMS= max signal before the speaker begins to break up, and max is the total amount you can push before damage.[/quote]Speakers are thermally rated according to specific EIA procedure, using power quantified by said Root Mean Square voltage.

[quote name='civictiger' post='689225' date='Dec 19 2009, 12:16 PM']ahh nice one mate

I was just wondering because I dont particularly like 115's. especially on their own. too boomy and thick for what i want.[/quote] You're not paying attention. Driver size and response are only peripherally related. Try a dozen different fifteens, you'll get a dozen different tones.
[quote]well, i guess a second 4x10 would never hurt anyone!

but, would it be worth it?
my amp atm is a 300w output, but the 410 I have with it atm is 250w (I think) so would adding another 410 even be worth it?[/quote]
Adding an identical 4x10 will give you 6dB additional sensitivity, the equivalent of quadrupling power. BTW, while your current 4x10 may have a 250w thermal rating it's most likely displacement limited to no more than half that. Thermal ratings alone aren't useless, but almost. Unfortunately no major manufacturer gives displacement limited ratings. Most don't even know themselves what they are.