Parts Express

[darien87]

Has anyone bought and had good results with any of the sub kits from Parts Express? I was looking at their website today and noticed that they had a 15" kit with 1,000 watt amp for $630. But when I asked a tech there for the frequency response of the sub, first he told me that it plays down to 19hz. But then he came back and said that it only goes down to the mid-30's!!! Mid 30's for a 15"!?!?! What a pile of crap. I get better than that from my Boston Acoustics 10"

Anyway, does anyone care to comment on Parts Express? I see their name thrown around here quite frequently.

 

[mike c]

a subwoofer that goes to the mid 30's like that PE kit is gonna be great for parties and most music listening. all that punch you feel in your chest comes from the 40-50hz range. and a low tuned sub will lose some of that effect, you can't have a sub that does both: a lower tune and a good punch a bit higher unless you put some more money into it.

 

[j_garcia]

What support probably didn't tell you is that sub will likely get REALLY loud, just not low like mike c said. Great for impact, but not if you are looking for low stuff.

You wanna hear low stuff? Come by my place...my 15" easily does low teens

 

[no. 5]

What support probably didn't tell you is that sub will likely get REALLY loud, just not low like mike c said.

PE's specs say 115dB.

But when I asked a tech there for the frequency response of the sub, first he told me that it plays down to 19hz. But then he came back and said that it only goes down to the mid-30's!!!

The driver itself will do 19Hz (as far as I know anyway), did the guy you called at PE say if the bass extension was measured anechoic, or with wall or corner loading?
Dumb question, but did he give you the frequency response for the TITSK-15K, or the DSUBK-15?

But, as far as PE goes, I have had good experience with them.

 

[Seth=L]

They never have the stupid DSUBK-15 in stock, but of course they have all the parts needed to make it on the site for more money.

I find it hard to believe that the Titanic 15 only goes down to the mid 30's, that sounds wrong. Are you sure he wasn't referring to the crossover or some other spec not related to overall extension? The description for the Titanic 10" kit says it is around the lower 30's just for reference.

 

[no. 5]

They never have the stupid DSUBK-15 in stock, but of course they have all the parts needed to make it on the site for more money.

I just checked a minute ago.... still out of stock.

I find it hard to believe that the Titanic 15 only goes down to the mid 30's, that sounds wrong. Are you sure he wasn't referring to the crossover or some other spec not related to overall extension? The description for the Titanic 10" kit says it is around the lower 30's just for reference.

I was wondering about that too, the DSUBK-15, and the Titanic 12 both go to 25Hz; so it's a bit weird that the best sub kit PE makes isn't better.

 

[Seth=L]

I think the tech support must have been on silly pills.

 

[darien87]

PE's specs say 115dB.


The driver itself will do 19Hz (as far as I know anyway), did the guy you called at PE say if the bass extension was measured anechoic, or with wall or corner loading?
Dumb question, but did he give you the frequency response for the TITSK-15K, or the DSUBK-15?

But, as far as PE goes, I have had good experience with them.

I believe I was asking about the TITSK-15K. He didn't say how the bass extension was measured. But he did mention that frequency response would depend on room placement.

 

[Swerd]

I believe I was asking about the TITSK-15K. He didn't say how the bass extension was measured. But he did mention that frequency response would depend on room placement.

The 15" Titanic III driver is an excellent subwoofer. At the sale price of $166 for the driver alone, it is a good deal. The TITSK-15K kit is also a good deal and easily compares with subwoofers sold for over $1000. The kit includes a 2 ft³ sealed cabinet and their 1000 watt plate amp. For movies, this subwoofer will produce huge slam. Note that the cabinet in this kit is not the same as the cabinet in their less expensive 15" subwoofer kit, which uses a lighter cabinet with less internal bracing.

As far as bass performance goes, it really does vary greatly on what cabinet you mount the driver in, what room you measure it in, and where in the room you place it. This is true for any speaker perfoming below about 200 Hz. So beware when someone says "my subwoofer goes down to 18 Hz". Exactly how that was measured makes a big difference.

Parts Express recommends a sealed cabinet of 2.1 ft³ volume for this driver, or a vented 5 ft³ cabinet tuned to 19.6 Hz with a 6" diameter × 33.5" long port. Most people choose the smaller sealed cabinet. PE says such an alignment will produce an F3 of 41 Hz. That means the bass response in a 2 ft³ sealed cabinet gradually begins rolling off at around 50 Hz, such that at 41 Hz the response has dropped by 3 dB. At lower frequencies the response will continue to drop at about 6 dB per octave. So at 20 Hz, one octave lower than 40 Hz, the response will be 6 dB lower than at 40 Hz.

A subwoofer in a vented cabinet will produce higher output down to the box tuning frequency, but below that it will drop off rapidly at about 24 dB per octave. But for this subwoofer, it requires a really big vented box.

 

[annunaki]

I recently did a sub kit from parts express for my parents new addition. I used the higher end cabinet with the Titanic mkIII 15" driver and the Dayton 500 watt amplifier. This sub has no problems getting into the 20hz range when setup correctly. We have it at about a 1/4 gain in a 3,900 ft^3 room. My Father still thinks it is a bit too much. It will rattle loose objects. I watched the movie Aragon with my father and brother the other evening and I even had to back it down some (-6.0 db) on the receiver as it was too much down low. It is a pretty good sub. With the 1000 w amplifier it has to be even better.

 

[Maceo23]

You Also might want to look at one of the Rythmik Audio servo kits. Alot of people are using them with the PE boxes and getting very good result. A great bang for the buck

 

[darien87]

You Also might want to look at one of the Rythmik Audio servo kits. Alot of people are using them with the PE boxes and getting very good result. A great bang for the buck

Forgive my ignorance, but what's that?

 

[j_garcia]

Rythmik makes amps and drivers, then all you need is an enclosure. I use the Rythmik A350 amp (which is non-servo) for my sub and I was really curious about their servo sub/amp setup because the A350 is a better amp than I was expecting for the price. Maybe one day I will build one...

www.rythmikaudio.com

 

[darien87]

All right. I got a little more info about the TITSK-15K kit from Parts Express. When I again asked a rep for frequency response, this is what he said.

"Maybe I am not explaining it well, 90% of subwoofer frequency response specifications are worthless for any sort of comparison. I can tell you that anechoic ally this sub begins rolloff at 34 hz and rolls off at 6 db per octave down to about 12hz."

Me: "So bottom line, it should have no trouble putting out decent SPL at 20hz?"

Chris: "in room it can yeild numbers as good as -3db in the low 20hz range easily but it does depend on the room"


So, basically I'm looking for an economical way get a sub that will play down to 20hz and below with good output and not be the size of a coffee table.

But when I asked him about passive radiators, he kind of threw me for a loop.

Me: "Thanks. You don't have any kits with passive radiators do you? I was hoping to go that route because it seemed to be the best compromise between box size and output.

Chris: "I do not agree with that actually. A passive radiator is just another way of tuning the box, no different than a port. for clean fast response a sealed box is far superior. it is also the smallest box size."

Me: "True. But don't you need WAY more power to get the same output from a sealed box as a ported box?

Chris: "no, that is a myth it is only true at the tuning frequency itself. since speakers aren't just pipes playing one frequency it doesn't hold up in real usage"


So does this guy know what he's talking about? It seems that, for the money, the kit is a great value. To put together a kit myself it looks like: about $200 for a driver, about $300 for an amp, plus the cost of wood and other bits. Also, I'm not a carpenter or anything, so who knows if I would even end up building a decent box. What do you guys think?

 

[j_garcia]

It does sound like he knows what he is talking about, but he is clearly of a particular opinion, and everyone is. It is not a myth that you need more power for a sealed design, but it also depends on what you are after. A sealed sub is less sensitive for a given amount of power vs a similar vented design. If you want solid output down into the teens, you WILL need more power. If you only want output down to the mid to low 20s, you probably don't need 2000 watts, where similar output can be achieved in a vented design with less watts, but also typically a different sound. *all generally speaking* Sealed has a tighter sound to it, but tends to lack some of the "rumble" due to not quite as much air movement. The cone tends to be a bit more controlled because a sealed box provides a bit more "spring" to it compared to a larger vented box. That is part of why you get away with a smaller box for sealed and why they sound tighter, or "faster" as some refer to it. There are tradeoffs to each design type. Vented designs tend to be larger but have a little more distortion, sealed are smaller and tighter but less sensitive, etc... With the right driver in a box properly designed for it, any sub can be made to sound very good.

From my reading, passive radiator can actually be harder to design properly than a sealed or vented design, with sealed being easier.

Room plays a HUGE role in how your sub sounds too, so he is right on with that.

 

[WmAx]

Chris: "for clean fast response a sealed box is far superior. it is also the smallest box size."

The box type is secondary to other factors. You can make any box type sound fine if you know how to properly design it, compensate for room response, and then adjust final target response according to user preferences.

Chris: "no, that is a myth it is only true at the tuning frequency itself. since speakers aren't just pipes playing one frequency it doesn't hold up in real usage"

The applicable tuning frequency of a subwoofer is very relevant! It concerns the lower frequency response of the unit, across a relatively wide bandwidth, where as a sealed unit would be ever decreasing in output relative to a fixed applied voltage amplitude input level, but where a ported system could have constant output level relative to a fixed voltage amplitude input level. To achieve the same response with the sealed system requires an equalization circuit to compensate. But doing so increases the voltage amplitude(and power) to the woofer as frequency lowers. To prevent clipping of the amplifier with the compensated sealed system in the same potential circumstances, as compared to a ported system, you require far more power for the compensated sealed system. In a non-compensated sealed system, you do not require more power -- you simply have less acousic output as frequency lowers.

-Chris

 

[billnchristy]

I think for $500 you should be able to build a sub that will almost rip the house apart.