Originally Posted by armystud0911
Bosso, how are you getting your tumults to get solid output to 3Hz? I can't even do that in a car, let alone a HT. Sure, you have 8 of them, that helps, are you sealing off a small room or something? Could you clarify on a few things, because you can come off as pretty snobbish in your posts, this is prolly just the internet, I am sure we could get along fine in normal conversation. From what I have gathered, and PLEASE correct me if I am wrong, but it seems that...
1. You don't waste your time with subs that don't do the full 3Hz-120Hz dolby lfe spec.
2. You don't waste your time with subs that are big, saying that people don't want them in their HT's
3. IB's are inferior because they rely on the suspension to restore the cone to center position
4. IB's are bad because they can cause the drivers to bottom if you were to power them with enough power to take advantage of them
5. LLT's are bad because they provide no output below tuning and are big
6. High powered amps do not cause very adverse affects with subs, you can power a beefy sub with lots of power in a small sealed alignment and the benefits of such a setup outweigh the problems of an LLT or IB
Perhaps if you could clarify some of this, I could move on to some of the touchier subjects.
It usually helps to read the thread. I simply pointed out that Ilkka's tests, though 80% comprised of commercial subs, is dominated by DIY, as is Tom Nousaine's list.
When you mentioned that Tumults and ACPs are too expensive, I listed real world examples of possible DIY subs that cost the same or less than and will out perform the better commercial offerings like PB-13, JL Audio, etc.
Two of the three examples I gave are ported subs.
Steve took exception to my observation of the FACT that Ilkka's tests are dominated by DIY sealed subwoofers by posting his usual (and quite tiresome at this point in his and my history on these boards) rhetoric that ported is better than sealed in a hypothetical situation.
This is fine with me, but elicits a response. Sorry if that doesn't meet with your approval. You win some, you lose some in that regard.
1. I've attempted to build a system that covers the Dolby spec. 'Tack' made some ridiculous statements regarding TH's specification like it was never intended to be utilized (not what TH told me), there are precious few sources that utilize the spec (get real, do I have to list them?) and that the spec, which has now gone lossless is actually a detriment because it only allows for 'mic clicks and dropped pallets'. Ear called it 'BS movie effects'.
To make it clear, I do have a system that covers the spec. I have A/B'd the system with many other more traditional systems using many sources. So, what would you have me do? State the opposite of reality to appease another's opinions? That's not gonna happen.
2. I have said a thousand times over the past 8 years that huge subwoofers are unnecessary, that they limit transient response, that they limit placement options, that they limit tune and Q options, that they increase group delay, that they emit higher driver (and other SC) noise and that they look pretty silly. I have 2- 280L ported 1X18" in my HT. They're finished pretty well, but they still look...well, as big as they are and offer nothing more than any other big ported sub can offer, that is: proportionally higher output across 1 octave and nothing below 10Hz.
3, 4. I've said all along that the claims that IBs are less colored because they have no box coloration is simply not true. ThomasW can attest to my opinions on this subject, which cover the gamut. I've never said they're inferior, just pointed out the +&- for the argument.
5. Correct. The lower the tune, the larger the box and pipe requirements.
6. Correct. People are too obsessed with maximum power models. One of the advantages to a sealed system is that you select the F3 and Q for various sources in various environments. This is not possible with a ported subwoofer of any design. The gobs of power are not used above F3 except for headroom for transients, which don't tax the system at all. They are used below F3 to maintain the desired F3 and system Q and to reproduce music program events as opposed to a continuous sine wave application.
TV has offered commercial ported subs with optional tunes, EQ and HPs and I don't believe there have been any DIY ported attempts at this, so you have to give him credit, but the problem with multiple tune ported subs is obvious in that each time you lower the tune, you restrict port area rather than increase it, and at each tune, your roll off is not optional and rather steep.
There are no such problems with a sealed system. Music program power handling is a walk in the park for drivers like the ACPs and LMSs. I've never had a problem with my system under the most stressful conditions. If I had, I would have mentioned it and addressed it, one way or the other.
I'm not really into posting a bunch of silly opinions. Everything I post is based on models, builds, measurements and listening to the various options.
Steve said "A reflex design (whether ported or PR'd) will always offer more performance than sealed. Since this discussion is about price per performance, keep in mind that ports will always be cheaper than a PR, and that two of the ported TC2ks would have outperformed the sealed LMS with performance and a lot of money left to spare."
Then Ear agreed with Steve that ported subs will beat sealed down low every time. I asked him to show an example. Instead, he said trying to reproduce to DC is a waste of time.
It was Steve who introduced the 'ported is better than sealed' into this thread, as he always does. This discussion is not about price per performance, it's about DIY vs commercial, which opens it to all aspects under the subject. Steve loves to make it about price per performance as long as he can define the criteria and ignore FR, size, Q, GD, TR, placement options, SC, transients, bottoming the drivers, stored energy, fit and finish and eliminate all subjective discussion, to which I reply...yeah, right.
One guy posted Craig's subjectives list and immediately Steve pisses on him. I find it interesting that Ilkka does strictly objective testing (though Ilk is smart enough to realize the validity of subjective input, he simply doesn't have the time or inclination to do both) and Craig does his own mixture of in-room tests that lean toward subjective criteria, yet:
Both have tested approximately 3 dozen subs. Though they aren't all the same subs, they're close enough by category.
Craig has the PB-13 @ #3 and the JL Audio @ #6 and Ilk has the PB-13 @ #4 and JL Audio @ #8.
Craig's top 10 consists of 6 reflex and 4 sealed and Ilk's has 6 sealed and 4 reflex.
Both of them cut off their tests at 10Hz.
Neither of them include flexibility features in the scoring.
Neither of them discriminate by price.
About the same number of people find either test results preferable and enjoy the hell out the discussions that result.
There is benefit in both of these guy's huge services to the internet audio world. Take them both out of the picture and what do you have, a better situation or a lesser situation?
There are only a small handful who deride one or the other for personal reasons.
Ear's comment about needing 125dB @ 8Hz is typical of the silly remarks that cause me to respond in a 'snobbish' manner. 2 years ago I posted an in-room graph of a single 2X15" showing a fairly flat response and 118dB at 10Hz with a quick sweep. Add 12dB to that with the addition of 3 more 2X15" subs and a few dB to compensate for the lack of accuracy of the QS at 10Hz and what do you come up with?
I've also posted an in-room graph to 2Hz which shows a room gain hump centered @ 5Hz and in-room F3 @ 3.5Hz, so it would appear that the evidence is clear enough.
To think that I should apply a HP filter at 10Hz or that in-room response to 3Hz is useless or otherwise unimportant to accurate reproduction, or that TH never intended his specification to be utilized in all Dolby hardware and software and most every DVD player on the market or that there is no application in source material, just because someone has that opinion, is what it is. A rather empty thought.