| chops |
Ok everyone, I have finally made up my mind for this subwoofer project that I've been thinking about for the last couple of months. I have so far thought about using PRs, but I ditched that idea. I also pondered the idea of going with a slot ported design, which I have also ditched.
So here's my latest, and most likely final design. *plain, simple, sweet*
I am going to run a total of four Dayton 15DVC subs. There will be two 8 cu.ft. sealed enclosures with two 15s sharing the same air space. I'm going to wire them so that each pair will be 2 ohms. I will then get a QSC RMX1450 amp to power them. This amp will give each pair of subs a total of 700 watts @ 2 ohms.
According to WinISD Pro, one enclosure will provide 104dB @ 15Hz with just over 500 watts of power, and that does NOT include room gain. Peak cone excursion (both ways) will be around 17mm which is well below the capabilities of these drivers. Group delay will reach a max of 7ms, also at 15Hz.
If anyone has any "guesstimates" on what the output might be with both enclosures running in a 13' x 17' x 8' room, feel free to share. :D
Anyway, here's a few screen shots from WinISD Pro. I just used the 15" Titanic Mk III as a reference (yellow). Please let me know what you all think also. ;)
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| simon5 |
16.7 mm peak excursion is more than the 15.1 peak excursion that woofer can do. It's not that much more so it'll be probably ok.
You'll have enough bass no matter what anyway with 4 woofers. |
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| chops |
| quote: | Originally posted by simon5
16.7 mm peak excursion is more than the 15.1 peak excursion that woofer can do. It's not that much more so it'll be probably ok.
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15.1mm is the Xmax in one direction, so the 15DVC should be able to peak at 30.2mm (both directions) and still be linear. |
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| simon5 |
| Yes but WinISD shows peak excursion, not peak to peak. |
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| chops |
| Well at any rate, I highly doubt I'll ever be dumping a full 500 watts into these subs anyway at any frequency. Just one 15DVC with this 115 watt amp gets pretty darn loud as is. ;) |
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| simon5 |
| Yeah, like I said, don't worry much hehe, you'll have enough bass. |
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| chops |
| So any thoughts on what my total output in-room should be with all four subs running? I'm just curious. I'm guessing maybe 113-ish dB at 15Hz?! :xeye: |
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| simon5 |
| I'd say around 120+ dB is possible if it's in a corner. |
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| chops |
| 120+ dB at 15Hz?!?! Holy cow, I better think about reinforcing my concrete walls. I don't want them falling over or anything! LOL :clown: |
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| Relax |
What made you move from dipole to multiple sealed subs?
Sound quality? Quantity? Different room? etc? |
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| chops |
| quote: | Originally posted by Relax
What made you move from dipole to multiple sealed subs?
Sound quality? Quantity? Different room? etc? |
Much more compact size more than anything else.
Sound quality? Not so much. I honestly do not think I'll EVER hear a subwoofer that sounds as good as those dipoles did, period. |
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| xstephanx |
all i can say is......
BY THE BEARD OF ZUSE!
but yeah, thats some SERIOUS output...oh and by the way winisd comes with the excursion grap set to one way by default, but youcan change it to p2p. this drivers are VERY VERYmuch like a tempest, comparing the uhhhhh...whats that machine called? to measure excursion a d or a u or SOMEHTING...ahh well, the measurments paper for that is even MORE frighteningly close to a tempest. and if i remember correctly, the tempests xmech is somewhere around 50mm p-p, you wont damage them....that said i wouldnt keep them at xmech on a daily basis, but if they go over linear limits for a transient, i wouldnt worry.
oh and in the future, can you post a trnasfer function graph too? or at least a full spl graph |
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| chops |
| quote: | Originally posted by xstephanx
all i can say is......
BY THE BEARD OF ZUSE!
but yeah, thats some SERIOUS output...oh and by the way winisd comes with the excursion grap set to one way by default, but youcan change it to p2p. this drivers are VERY VERYmuch like a tempest, comparing the uhhhhh...whats that machine called? to measure excursion a d or a u or SOMEHTING...ahh well, the measurments paper for that is even MORE frighteningly close to a tempest. and if i remember correctly, the tempests xmech is somewhere around 50mm p-p, you wont damage them....that said i wouldnt keep them at xmech on a daily basis, but if they go over linear limits for a transient, i wouldnt worry.
oh and in the future, can you post a trnasfer function graph too? or at least a full spl graph |
Hey, thanks for the excursion graph tip. I changed it in WidISD.
BTW, I just got done watching "Finding Nemo" and that Darla scene where she taps on the fish tank... WOW! I have to say, with only 115 watts going to this sub, it shook the entire room just as much if not more than the SVS sub I had, and that had dual 12s and 600 watts! I seriously can not imagine what 4 of these 15s are going to sound like in here with some power behind them. :eek:
Also.... Ask and you shall receive. :D
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| xstephanx |
thanks for the graphs, just what i needed to brighten up my grade 10 computer engineering class.
oh yeah, that machine thing is called DUMAX, but yeah i remember hearing alot of buzz on car audio forums of how similar the sheets on the dvc and the tempest were....errily close. in fact i consider the dvc 15 as completely interchangeable with the old tempests. i would assume that the xmech would also be the same, in which case your excursion graphs show NO real excursion problems IMO, i mean its not like youre going to be pumping out 20hz sine waves at full power capacity....just for fun...well not more than a couple of times :D. |
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| chops |
| quote: | Originally posted by xstephanx
thanks for the graphs, just what i needed to brighten up my grade 10 computer engineering class.
i would assume that the xmech would also be the same, in which case your excursion graphs show NO real excursion problems IMO, i mean its not like youre going to be pumping out 20hz sine waves at full power capacity....just for fun...well not more than a couple of times :D. |
You're welcome. Not a problem at all. ;)
And I too think that I'll be fine with the excursion limits. Like you said, it's not like I'm going to be running them full blast all the time.
Besides, with the combined effeciency of all 4 drivers (all 8 VCs) plus room gain, I'll probably be looking at something like 100+ dB @ 1 watt or something like that. So in other words, I won't even have to dump a lot of power into them anyway to get some high levels. As it is, I'm rattling everything in my house with only 30-50 watts peak so far! :bigeyes:
Say, that's a good question for you guys... Is there any way to guess how effecient these subs will be in my room? (13 x 17 x 8)You know, just for sh**s and giggles. :D |
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| batdorf9 |
I'd recommend a single 15 DVC in the 8 ft3 box but ported instead of sealed. You can even use a huge 6" dia port (to reduce port compression and lower air velocities) and the length is still reasonable. This would give you slightly more output at 20 Hz, but at a lower cost.
Better yet might be two 15 DVC's in 12 ft3 (if you've got room), also ported and tuned to around 15-20 Hz. More output and likely lower distortion at a given SPL.
I don't wish to start another ported vs. sealed debate, just my $0.02.
-Robert |
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| bender460 |
| Have you thought of infinite baffle? |
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| chops |
Thanks, but no thanks.
I do not want to go ported. (extremely low group delay is KEY in this project).
And I do not want to go IB either. I'm not about to go crawling around in my small attic. And I have no adjacent rooms to mount them in. |
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| xstephanx |
in that case....why not dipoles?! ahahaha just joking, but seriously, run some sims with REALLY low port tunings, like 11 or 12 hz kinda low, and look at the group delay for 20hz and above. I dont think theres aman alive that would notice even MASSIVE amounts of gd below 20hz, since all of that information is just rumbles and compressions anyway.
by doing that you can also reduce your excursion by a large amount (sometimes, if you tune to low youll actually increase excursion.
but yeah jsut something to poke prod and tinker with for hours on end in winISD.
ahhh my cinnamon bun is here, being sick aint that bad, exept that your ear is so plugged that it screws enough soudnstaging enough that the drums are behind you! |
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| chops |
| quote: | Originally posted by xstephanx
in that case....why not dipoles?! ahahaha just joking, but seriously, run some sims with REALLY low port tunings, like 11 or 12 hz kinda low, and look at the group delay for 20hz and above. I dont think theres aman alive that would notice even MASSIVE amounts of gd below 20hz, since all of that information is just rumbles and compressions anyway.
by doing that you can also reduce your excursion by a large amount (sometimes, if you tune to low youll actually increase excursion.
but yeah jsut something to poke prod and tinker with for hours on end in winISD.
ahhh my cinnamon bun is here, being sick aint that bad, exept that your ear is so plugged that it screws enough soudnstaging enough that the drums are behind you! |
So you're only reason for me tuning that low is to lower the overall excursion?
Granted, it DOES drastically lower it, but I really don't think it will be worth the extra work and airspace needed. |
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| xstephanx |
| by lowering distortion you are also lowering distortion, if you get the same output with less cone movement thats less distortion(im sure youre famliar with this), plus youd have more headroom, plus you can get gd very close, oh yeah and a flatter FR curve to boot. People normally dismiss a ported design cause they think its high q, boomy, and has high gd, but a well implicated vented design can sound just as good as a sealed design IMO. oh and proably a little edge in output(like you need it hahaha) |
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| batdorf9 |
paul has posted this link before, but i'll repost it. i thought it was great to read about all the different designs out there, see test data (and at far greater levels than 1W in), and hear listening reviews of all these different subs.
http://www.ultimateavmag.com/features/604way/
in my own experience, i'm much more sensitive to distortion than to group delay.
perhaps you should design for both ported and sealed. use the same size box for both. make one ported and the other sealed and do some a/b testing.
- Robert |
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| chops |
Yeah, after more thinking about it, I think I am going to go with the ported enclosure. And I also think I can still use 8 cu.ft., gain a little more output (not really needed at this point... LOL), lower the excursion conciderably which will ultimately lower the distorsion. The gd is still low, around 11m/s @ 20Hz!
The only problem is, I need someone to help me figure out the actual displacement that the port and drivers are going to take up so I don't loose too much airspace for the drivers. I want the drivers to have a total of 8 cu.ft, so the enclosure will probably have to be in the neighborhood of 9.5 cu.ft. or something which I think is about the MAX size I can go. I'll have to double check though.
The mouth of the port (inside dimentions) is going to be 2.5" x 13" and I think the total length is going to be right around 60". Oh, and if I can find it, I will be using 1" MDF, but if not it will be the typical .75" MDF.
To help save some space, I'm going to try placing my center channel vertically to see how it sounds. Def Tech claims that it can be used either way with great results. We'll see.
If I have time at lunch today, I'll try taking some more measurements to see how much space I have to work with. |
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| chops |
I have another question, however I'm not sure if it should be posted here or in the amplifier section, but...
The two possible amps that I'm looking at to power these subs are:
1) Crown XLS - 402 (570W @ 2 ohms x 2 ch / 1140W @ 4 ohms mono)
Damping Factor: (8 ohm) 10 Hz to 400 Hz: >200.
2) QSC RMX - 850 (430WW @ 2 ohms x 2 ch / 830W @ 4 ohms mono)
Damping Factor: Greater than 300 at 8 ohms from 1000Hz and below.
Now I know that the damping factor is what helps control the movement of the driver(s) in some way, but according to this site, they claim it's not AS important as people think.
http://www.audioholics.com/techtips...mpingfactor.php
How much attention should I pay to the damping factor? The amp will only be receiving a signal of 80Hz and below. |
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| batdorf9 |
hopefully it wasn't peer pressure that led you to go ported. :D that port sounds really long though, and i suspect you'll need to bend it to fit. collo pointed out (or some of the other research papers did) that bends in a port are not so good. i'd tune just a bit higher to avoid the bend.
the general internet consensus is that the crown xls stuff shouldn't be labeled crown and should be avoided. for all i know that could just be internet legened as well.
qsc rmx stuff seems to have a better reputation. there's a ton of decent used stuff on ebay, so that may open a few more options as well. just look in the musical instruments / pro audio / power amplifers category. (as opposed to the relatively sissy stuff in consumer electronics) be aware most pro amps have cooling fans, so you may have to deal with some fan noise.
if you look at specs for amps, most are frequently rated power at 1kHz. in some cases they also list power from 20hz-20khz and it's always lower than the power at 1kHz. if you look at either the xls or rmx specs, you'll see they conviently don't list the 20Hz-20kHz power. this makes me suspicious. so i'm not sure you should expect to toss 2-ohm subwoofer duty on the cheapo amps and expect to have anywhere near the rated 1kHz power.
for example, note qsc doens't list a power value for 2-ohm, 20hz-20khz here http://www.qscaudio.com/pdfs/rmxspc.pdf.
if i were in your shoes i'd consider (assuming used ebay prices, not new) a crest ca4 http://www.crestaudio.com/media/pdf/ca4_11-25-97.pdf or perhaps some older yamaha stuff (cheap for what you get).
i don't have a clue how much attention you should pay to damping factor. generally better amps have higher damping factors.
- Robert |
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| chops |
| quote: | Originally posted by batdorf9
hopefully it wasn't peer pressure that led you to go ported. :D that port sounds really long though, and i suspect you'll need to bend it to fit. collo pointed out (or some of the other research papers did) that bends in a port are not so good. i'd tune just a bit higher to avoid the bend.
- Robert |
Well that's one of the nice things about building a slot port that's large enough to have a low air velocity. Having one bend it in should effect the performance of it that much, if any at all. |
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| chops |
| quote: | Originally posted by chops
Having one bend it in should effect the performance of it that much, if any at all. |
Woah, what was that?! LOL
What I meant to say was...
Having one bend in it shouldn't effect the performance. :xeye: |
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| bigwill |
| Make the port diagonal if you want it longer, no bends :D |
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| mondaycurse |
| What's your VA look like with the ported design? It might be good do get a good BASH amplifier for their high effeciency with high VA. |
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| chops |
Just an update here...
I just ordered all three 15" Dayton drivers this morning, so they should be getting here in about a week or so and I can finally start this little project.
Also, I have once again slightly changed the design of the enclosures. I moved my projector screen a little higher up on the wall, so now I can build these enclosures to a usable volume of 12 cu.ft each, and still tuned to 12Hz.
With the vent opening staying at 2.5" x 12", the new length of the port will only be 42" long. Air velocity is at an all-time low of 7.5 s/m @ 20Hz, 11.8 s/m @ 15Hz, and cone excursion reaches 26.5mm p-p @ 24Hz!
Yeah.... These are going to be some good times pretty soon. :D |
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| xstephanx |
wow while my internet was dead i looked at 12 tuned to 12hz and also noticed it looked exeptional...
good luck on building them things, theyre gonan be HUGE and should sound exeptional. What mains are you pairing them up with?
mmmm noodles are ready! |
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| chops |
| quote: | Originally posted by xstephanx
wow while my internet was dead i looked at 12 tuned to 12hz and also noticed it looked exeptional...
good luck on building them things, theyre gonan be HUGE and should sound exeptional. What mains are you pairing them up with?
mmmm noodles are ready! |
My mains are Definitive Technology BP10Bs, and a C/L/R 2000 center channel.
If I can get a hold of my brother's SUV this weekend, I might go get the MDF and start on these things. I have a Miata so I obviously can't get it with my car. LOL :clown: |
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| xstephanx |
dont be a wuss! just buy two 4x8s and attatch them to the car as wings...anndd er fly home? i dont know really.
no offence, but i wouldnt expect someone who drives such a small efficient car to have such large burly subwoofers! not hating on mazda, both my parents own one...but with a sub like that id guess you drive a hummer :| |
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| chops |
| quote: | Originally posted by xstephanx
no offence, but i wouldnt expect someone who drives such a small efficient car to have such large burly subwoofers! not hating on mazda, both my parents own one...but with a sub like that id guess you drive a hummer :| |
Yeah well, none taken. And you should have seen what my plans were for the stereo system in that Miata. I was going to be pumping about 1000 watts into two 12" Treo subs with a 54mm Xmax! But I decided that might be a little too much for the trunk and car, so I sold it all before I ever installed it and used the money to put towards my home stereo and a healthy computer upgrade. :D |
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| xstephanx |
| id tend to think that 1000 watts is underpowered for two heavy duty 12s in a car enviroment. there are plenty of peoepl running 1.2kw to single sealed high excursion 12s. |
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| simon5 |
I didn't know that such extreme subwoofers existed.
Treo CSX line is very interesting, I mean who could go wrong with a 18 incher with 71.33mm (2.81") Xmax one-way... |
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| chops |
Quick question...
I'm going to be building these subs pretty soon and just wanted to know how exactly to figure out the air displacement of the port. It's going to be in the neighborhood of 2.5"W x 13"H x 46"L.
Do I just figure it out like building a normal exclosure (0.87 cu.ft.) taken away from the internal air space of the sub enclosure?
The drivers NEED 12 cu.ft. per pair, so I would have to build the enclosure out to almost 13 cu.ft. so the subs have 12 cu.ft. of air space after driver and port displacement?
Does all of this sound right to you guys?
Thanks! ;) |
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| xstephanx |
| sounds perfect to me. alot fo people dont knwo this but theres alto fo leeway with ports because the sims you get arent perfect, and becuase usually port tubnings are LOWERR than what calculations woudl suggest. and are you sure thats not 70 some od mm both ways? if thats 6" p-p LINEAR..... i think ill soil myself. |
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| chops |
| quote: | Originally posted by xstephanx
sounds perfect to me. alot fo people dont knwo this but theres alto fo leeway with ports because the sims you get arent perfect, and becuase usually port tubnings are LOWERR than what calculations woudl suggest. and are you sure thats not 70 some od mm both ways? if thats 6" p-p LINEAR..... i think ill soil myself. |
Thanks! That's what I needed to know. ;)
And yes, that IS 6" p-p linear! :bigeyes: :eek: :hot: |
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| boydon_lepasci |
| You might want to go even bigger than 13ft^3 gross. At that size you'll be making a wood balloon if you don't brace properly. |
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| chops |
With external enclosure dimentions measuring 23"H x 27"D x 46"W, and using 1" MDF, total internal air space before the port, bracing and drivers will be 13.4 cu.ft. The port will be taking up about .9 cu.ft. of space on its own which will leave .5 cu.ft. for the drivers and bracing to use, getting the total internal air space down to 12 cu.ft. after displacement.
If this is cutting it a little too close for bracing and driver displacement, I can always build the enclosure up a little taller. If I go to my MAX height of 27" (external) the enclosure will be 15.9 cu.ft. before any displacement, so I have plenty of room if needed.
Does anyone know how much air space these Dayton 15DVC drivers displace? Also, how much extra space should I give myself for extensive bracing? |
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| simon5 |
| I think it will be ok. I think .5 cu.ft is enough for bracing and drivers. |
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| chops |
Ok, new problem...
I have retired my Def Tech loudpspeakers as the mains and have reinstated my Klipsch Cornwalls which are considerably larger. So in other words, my current subwoofer design is not going to fit.
I was thinking, what kind of bass response can I expect from building two towers for the subs and the drivers actually mounted about 3' and 6' above the floor? The towers will be installed in the two front corners of the room directly behind the Cornwalls.
Building the towers would allow me to conceal the enclosures with red curtains on either side of my 9' projection screen.
If I use .75" MDF, I can build them (outside dimensions) 90" tall, 23" wide and 12" deep. Internally, this will give me 11.6 cu.ft. of airspace before driver and bracing displacement.
Also, with the enclosures being 90" tall and 23" wide, I can still tune them to 12Hz and only have one bend in the port, with the port running along side the drivers and the opening exhausting at the bottom of the enclosures on the floor.
Any suggestions and/or thoughts? |
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| chops |
| Also, how would I figure out the port length if I use a straight port like the one on the left and just have an opening on the side of the enclosure? Or would this even work properly? |
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| Bogie |
I'm getting ready to add two more Dayton Quatro 15s to my basement... Two are probably enough, but I bought four when they were on sale...
And I just bought a Crown XLS602 from Guitar Center on sale for $249.99.
I had been using a pair of the PE 240 watt plate amps to drive the subs (5.5 cubes, ported to 18.5), and I knew things would be different...
1) Crown amp sounds a LOT better. More detailed bass.
2) Blackhawk Down's Irene scene, even at reduced volume, made me HIGHLY aware that the pro amps do not have rumble filters installed. 5hz bass is VERY interesting to watch. And it looks like the only way to get one is to build it myself.
If you hear of a pre-built sub-20hz 2nd order or better rumble filter, please let me know. |
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| chops |
| quote: | Originally posted by Bogie
I'm getting ready to add two more Dayton Quatro 15s to my basement... Two are probably enough, but I bought four when they were on sale...
And I just bought a Crown XLS602 from Guitar Center on sale for $249.99.
I had been using a pair of the PE 240 watt plate amps to drive the subs (5.5 cubes, ported to 18.5), and I knew things would be different...
1) Crown amp sounds a LOT better. More detailed bass.
2) Blackhawk Down's Irene scene, even at reduced volume, made me HIGHLY aware that the pro amps do not have rumble filters installed. 5hz bass is VERY interesting to watch. And it looks like the only way to get one is to build it myself.
If you hear of a pre-built sub-20hz 2nd order or better rumble filter, please let me know. |
And all of that totally unrelated stuff helps me how?
BTW, I very highly doubt you are getting anything near 5Hz out of your preamp/receiver at any decent volume level. |
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| Bogie |
| quote: | Originally posted by chops
And all of that totally unrelated stuff helps me how?
BTW, I very highly doubt you are getting anything near 5Hz out of your preamp/receiver at any decent volume level. |
Okayyyy.... I noticed you are planning on using a pro amp, and I thought I would let you know about a possible problem, and whammo... I guess that'll teach me to think... but I'll play nice-nice...
FWIW, and you can check SVS, etc., on this... The "Irene" scene in Blackhawk Down has some _very_ low, and _very_ loud 5hz bass... And I had to watch it to see what it'd do. With the volume way down, about 18 below where I normally have it set for movies... Granted, it ain't gonna seem "loud," but it was really darn trippy watching a pair of drivers maxing out that slowly. Looked like a 3d movie. If I had not known what to expect, I likely would have had a pair of dead drivers.
If you're like me, your previous subwoofer amps had subsonic rumble filters built in. In my case, a 2nd order at 20hz... Yeah, you lose a little, but it protects your drivers from severe overexcursion. If you'll look at a typical WinISD plot, you'll notice that in ported design, cone excursion typically peaks, drops, and then goes through the bloody roof. Sealed speakers don't do this - but the excursion goes up at a higher frequency, albeit with a shallower slope, and it stays up....
Heat doesn't generally kill subs. Excessive travel is what does it. I have a friend who has done it to a pair (and not simultaneously either...) of Adire Tempests in a 340 litre sonotube. Next time I house sit for him, I'm gonna cut about 3' off the puppy...
Now, if you're going to figure on underpowering them, that's one way of minimizing the problem. Just looked at four 15" DVCs. IIRC, you have them in oversized boxes. It'll probably sound nice. But if you do not put in a hard cut down way low, the first time you hit some very low loud LFE/HT/Telarc 1812 bass, and you and your friends are watching something nice and loud, you're gonna have some dead speakers. With four DVC 15s, in 24 cubes total, I'm getting some impressive numbers - but with a sizable signal at 5hz, you're going to be running 'em 50mm... And I think WinISD figures one way... Oops.
Now, running the four drivers sealed in 18 cubes, with 700 watts available, and a Qtc in the low sevens gets you darn near the same performance, and your speakers are within xmax limits down to 5hz...
So, the bottom line - I'm going have to locate/build a filter to cut my low end... If I go 2nd order, I'll probably place it about 17hz or so... Yeah, I'll miss out on ultra low stuff, but I won't be buying new drivers every time I have a party. |
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| Bogie |
| Oh yeah - as for volume... My front speakers each get 300 watts (bridged Hafler 2xx amps), and my sides and rears are run from some Hafler DH-500s... I was using a pair of 240 watt plate amps to run the subs, but now I've got the XLS602... So I think I can play loud enough... I'm just going for more clarity and definition with the subs now... I _did_ see a remarkable improvement going from the 240s to the pro amp. But without the low end protection, I'm going to be playing it safe for the time being. |
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| chops |
Not the point at all.
I have been running sealed, ported and even open baffle subwoofers in my systems for years now with regular home audio or pro audio amps, with and withouth subsonic filters. I know what to expect and I know what the drivers will do at what levels and at what frequencies.
WinISD measures in both 1-way and p-p. You have to set it the one you want.
The amp I'll be getting has a peak output of around 600W @ 2 ohms per channel, and it has a built-in bypassable subsonic filter @ 12Hz.
I was not referring to volume. What I was getting at was that most preamps, receivers, amps, whatever; they may be rated to 5Hz or even 2Hz, but once that volume is turned up to a normal listening level, the bass freq resp of that equipment usually rises very rapidly and you only really have bass extension down to about 12Hz or 15Hz, not 5Hz.
My main point to your first post is that it had absolutely nothing to do with what I was asking about.
And since no one seems to like me here anymore (which I don't care either way) I already found my answer from a much better, more reliable source. |
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| simon5 |
And who is that amazing source? BTW, you don't need to be rude with everyone in there.
To answer your question, both drawings would work. Length for a port with a corner, you calculate the average length, in the center of the corner. Then since your port ends on one side of the box, you add half the diameter of the port to the length. |
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| Bogie |
| I guess I didn't see the drivers moving point/point in huge way then... |
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| crippledchicken |
| hi there, have you tried the sub with any music? if so how does it perform? the reason i ask is i was thinking about buying one and my main use is for mostly music running it sealed. thanks! :) |
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| Bogie |
| I've got a friend who has a 15" DVC in a 340 litre sonotube - replaced a couple of adire drivers. It'll go VERY low, and sounds reasonably nice, but if he runs it loud, he's gonna tear it apart. I haven't tried one of those in a sealed box yet. Right now, I'm running a pair of 3 cubic foot boxes with Quatro 15s under my maggies, and I really like them. |
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| crippledchicken |
| hi Bogie, i've heard alot about the Quatros for HT. and i was thinking of replacing my Atlas 12 with a 15" driver but, i will be using for 2 channel home music system and was just wondering if it would be an upgrade? or would i loose some SQ. which is my main goal. the Quatro seems to plot out pretty nice in BassBox 6 Pro. but as always, the human ear makes the best tool for sound judgement! thanks for any input. :) |
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| chops |
For now, I'm running a single Dayton 15DVC driver in a 4 cu.ft. sealed enclosure. When I first built it, I was using one of those cheap 250 watt Rythmic Audio plate amps. Those amps suck and it made the sub sound like garbage. Fortunately the dumb thing died. Now it's just sitting on the back of the enclosure filling the hole I made for it.
Now I'm powering it with an old Technics SU-8099 integrated amp which is only giving the sub 115 watts per VC and now the sub sounds excellent. It plays a heck of a lot cleaner with a lot more detail, it blends in better with the rest of my system, plays louder and lower and is just an all-around great sounding sub now.
If you decide to replace that Atlas with the Dayton, just be sure to stay away from that Rythmic junk. Use a good quality amp and you'll be happy. |
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| Bogie |
Don't be shy at throwing power at 'em. You're going to overexcurse them before you melt 'em, and they'll self-destruct that way LONG before you let the magic smoke out by nuking the voice coils... My "150 watt rated" home theater speakers are fed between 255 and 300 watts apiece - I don't "use" it all, but it's all clean.
One of my next projects is to find a larger fanless amp for my maggies. They're only getting a Hafler DH-200, but it is SO clean, and it'll run 125 wpc before clipping into 8 ohms, so with the four ohm maggie load, I'm guessing 175-200ish... I'd like to stick a 400wpc amp on 'em. |
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| chops |
Since I'm going to be buying a 600 watt amp for them, I don't think that could be considered "shy".
When I had my Maggies, I was pushing 350 watts RMS to them. I'm running 110 watts into my Klipsch Cornwalls right now, and for these speakers, 110 watts is major overkill. |
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| crippledchicken |
| one amp i for sure, stay away from is the PE 240 watt. i don't know if i had a lemon or not but the amp had to be run at about 3/4 gain to get much out of it which many, have complained about. also, there are two 1/4 watt resistors in that amp that run extremley hot! when i say hot, i mean they cooked black and crumbled? the coating fell off of them and this is at idle with no input. i don't know if anyone else has looked inside of theirs or not but, might want to sometime! i was told by the company that was normal? i'm no EE. but, i know enough about electronics to know 1/4 watt resistors running that hot to where they cook black and fall apart is for sure, not normal. also the amp was never pushed hard in this small room of mine. so that turned me away from those particular model amps for sure hehe! thanks for the replys! :) |
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| Bogie |
My 240s haven't had any problems... Granted, I do have the gain on 'em turned up, but they managed to keep up pretty well with my bud the drummer's Who obsession...
FWIW, I've also got the gain knobs maxed on the XLS602 I just bought - I do the "volume fine tuning" in my AVR... |
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| Bogie |
Yawn. I think that the main reason the pro amp sounds better than the plate amp is just sheer headroom.
Guys, your subwoofer is not an extension of your penis. Besides, mine are bigger. |
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| chops |
| quote: | Originally posted by Bogie
Yawn. I think that the main reason the pro amp sounds better than the plate amp is just sheer headroom.
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The SU-8099 is not a pro amp. It's an old top-of-the-line Technics from 1979 when Technics still made good equipment. Heck, the darn thing weighs nearly 60 lbs.
| quote: | | Guys, your subwoofer is not an extension of your penis. Besides, mine are bigger. |
LOL! :clown: |
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| Bogie |
There's a big difference between the old big iron, and the new "digital ready" stuff... If you have an amp that's allegedly rated at 100 watts x 7 channels, and it uses a peak of four amps, someone's lying.
The old Technics are okay, but I've got a friend who has one of the monster Pioneer silver face receivers, and you can weld with it. My Marantz 2230 will do 35 watts/channel cleanly, and it'll do it all day long. It also weighs a bunch. |
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| simon5 |
You obviously got a defective amplifier, but need to bash the company on every forum you write on.
I've used the Rythmik amplifier you talk about and the result was outstanding. It's playing at outrageously loud levels everyday for more than a year and it's going well.
I'm sure if you send that amplifier to Rythmik, they will fix it. If you don't want it anymore, send it to me or someone else who will get it fixed and have fun with a good plate amplifier like that. |
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| Bogie |
The proper way to test an amplifier.
Turn up the gain.
Take both leads, insert in mouth.
Flip da switch.
A friend actually did this, albeit with a Hafler DH-225 that had a bad mono/stereo switch (discovered that the switch was bad by wiggling it, and then getting off the floor). |
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| chops |
| quote: | Originally posted by simon5
You obviously got a defective amplifier, but need to bash the company on every forum you write on.
I've used the Rythmik amplifier you talk about and the result was outstanding. It's playing at outrageously loud levels everyday for more than a year and it's going well.
I'm sure if you send that amplifier to Rythmik, they will fix it. If you don't want it anymore, send it to me or someone else who will get it fixed and have fun with a good plate amplifier like that. |
It's apparent that I got a defective amp, no doubt about it. And yes, maybe I'm wrong to keep saying that they're junk, but the improvement in sound quality is very obvious when I switched over to the Technics.
So yes, I'm sorry for saying that Rythmik is junk. |
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| Bogie |
-clue bat mode on-
You know, normally if I buy something, and it either doesn't look like the picture on the box, doesn't taste anything like chicken, or doesn't make my speakers make the right noises, I send it back with a polite note saying that something obviously isn't right, and then they send me something that -is- right.
From this end, it is looking like you're getting far more enjoyment of the fact that it didn't work to your expectations than you EVER got from something that did. Reminds me of when I was working retail... Customer got a faulty item. Told me about it at length. I offered to replace it. Nope, that wouldn't work either. What would work? I'm not really sure, but it more or less involved me standing there listening to 'em rant for about 20 minutes until the department's manager showed up and suggested that they had two choices. Bring it in, and leave, or keep it at home, and leave.
Now to go plug the 2nd 240 watter into the second upstairs maggie stand... |
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| Bogie |
Well, I'm really not sure what's going on, but I think someone somewhere needs to move the decimal point a little to the left on the dosage...
Plug it in, turn it on, **** off the neighbors - it used to be so simple... |
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| chops |
| quote: | Originally posted by Bogie
-clue bat mode on-
You know, normally if I buy something, and it either doesn't look like the picture on the box, doesn't taste anything like chicken, or doesn't make my speakers make the right noises, I send it back with a polite note saying that something obviously isn't right, and then they send me something that -is- right.
From this end, it is looking like you're getting far more enjoyment of the fact that it didn't work to your expectations than you EVER got from something that did. Reminds me of when I was working retail... Customer got a faulty item. Told me about it at length. I offered to replace it. Nope, that wouldn't work either. What would work? I'm not really sure, but it more or less involved me standing there listening to 'em rant for about 20 minutes until the department's manager showed up and suggested that they had two choices. Bring it in, and leave, or keep it at home, and leave.
Now to go plug the 2nd 240 watter into the second upstairs maggie stand... |
That's not the case at all. I had that Rythmik amp running that sub for a couple years before it started giving me problems. And since I bought that sub and amp at the same time and NEVER powered the sub with anything else but that amp, I had no idea if the amp and sub were providing the best possible performance or not.
It was only into the beginning of the third year that the amp starting buzzing, and that buzzing kept getting louder and louder. Shortly after, I sent an email to Rythmik and never got a reply back. At that point the buzzing got so bad that I just stopped using it and bought an SVS PB12-ISD/2 sub. I had that for a while and decided to sell it. I then tried using my old sub again, but the Rythmik amp never powered back up after sitting for about 6 months.
The driver is still in great shape, hence the reason why I decided to use the Technics amp on the sub just for a while until I get the other amp and subs built. That's when I discovered that the Technics amp on the Dayton sub sounded much better than the Rythmik/Dayton combo ever did.
So it isn't like you say... That I bought the amp and didn't like it right from the beginning. That's not the case at all. In fact, I was rather happy with it. The only REAL complaint I ever had with that amp was that it got so darn hot you could fry eggs on it, but I guess that's normal since I have heard that from others as well. |
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| Bogie |
| Well, to me it's sounding like he ran it for a while, and it ran hot, and eventually got terminally toasty... I wonder what the actual load was on it... I've only thrown an amp into shutdown once (The Who's Quadrophenia DVD that came out last year), and the amp that threw in the towel was my center channel. I'm guessing that speaker really isn't an 8 ohm speaker (MTM? Hmmm....) like the specs say... I have added a fan in the closet tho... |
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| ShinOBIWAN |
| quote: | Originally posted by Bogie
Well, to me it's sounding like he ran it for a while, and it ran hot, and eventually got terminally toasty... I wonder what the actual load was on it... I've only thrown an amp into shutdown once (The Who's Quadrophenia DVD that came out last year), and the amp that threw in the towel was my center channel. I'm guessing that speaker really isn't an 8 ohm speaker (MTM? Hmmm....) like the specs say... I have added a fan in the closet tho... |
Running low imp. loads with most panel amps isn't a great idea but even the most basic panels have protection circuity for operation that exceeds original parameters.
And this isn't really directed at anybody in particular:
Whats the power supply like in the Rythmik's? The two budget panel amps that I've tried here in the UK were both undersized. For bass you really do need a great PS. There's no doubting that 'value for money' is a great thing though but a decent PS isn't entirely associated with 'budget'. And lets not forgot that nearly always something 'better'.
I also highly doubt that the Rythmik are junk but chops already said that was wrong.
Can't see what the problem is. Guy has Rythmik panel for 3 years, he's happy with it but then it develops problems and dies. He revisits the project and discovers new found performance by swapping out just the amp. I read stuff similar to this all the time on here and nobody reacts the way AJ did. You need to get thicker skin m8, I take pride in owning various brands of kit but I wouldn't take to insulting someone else over such a trivial word as 'junk' and especially when you consider the history that chops had with the Rythmik panel (he was happy remember), he just found something better that's all. You should be happy for him if anything. |
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| SY |
:captain:
AJ- rule of thumb, if a post uses terms like "imbecile" or "pathetic" or "moronic" or "idiot," it's rules-breaking. Take two days away from this thread to cool off, and if you want to post after that, keep personal invective out of it.
No further warnings. |
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| Bogie |
| When you let the magic smoke out, the things in the expensive boxes don't work anymore. |
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| jadenlinkletter |
first of all, your all nuts, except for chops. leave the guy alone its his thread and your not helping his questions in any way, plus your making a fool out of yourselves in the mean time and drivin chops right up the wall
ok chops, i own a dvc, my friend owns 2 of them and i've seen it in many boxes
3.5 cubic feet sealed sounds pretty good
i tried it at 3.5 cubic feet ported, and that sounded alright but it just dind't unfold the sub like it could have, so i sold it to one of my car audio customers and its a perfect allignment for car audio,. BTW it was tuned to 35 hertz with two 4 inch prots, stricly for music, althougt it had impressive subsonic outputs wheni tried it in home theatre.
now my buddy, he has two of theese drivesrs in 10 cubic foot sonotubes tunes to 12 hertz, sounds amazing with musci and everything extreme spl and virtually seamless.
i think putting them in sonotubes is the solution to your space problem, 100%
Linkletter.
i dont want to hear onesingle word out of you dummy's mouths, you know who you are |
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| ShinOBIWAN |
Haha
Was expecting just that, here's another word 'predicatable'.
So now I'm daft for pointing out that insulting a forum member so blatently isn't particularly cool? -Sure thing AJ. And what's your point with regards to chops? He's made some opinions that you don't agree with and therefore he should be ridiculed and insulted? -Brilliant attitude.
Like I said before, engage brain next time. And see you in two days :D |
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| ScottG |
No, one post qualified the other - there IS a difference. What you are doing is stripping out the context and fabricating a false conclusion.
Nor did he insult another member, rather he opinioned a negative view of that other member's commmercial product. There are two significant differences here:
1. It is not personal. (rather you have deemed it personal.) Instead it's about an object.. more specifically a product (not a person).
2. It IS a product. (i.e. part of a commercial venture.)
Remember it is HIS OPINION - NOT YOURS (or anyone elses). Respect his opinion if not his conclusion AND understand the difference, stopping making things personal, and enjoy life (rather than making it hard on others). |
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| ShinOBIWAN |
| quote: | Originally posted by Bogie
When you let the magic smoke out, the things in the expensive boxes don't work anymore. |
Remember not to smoke the magic smoke though. |
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| chops |
Seems like I missed all of the fun stuff again. Oh well, it's for the better.
On a side note, I noticed that this thread went on a diet since my last visit earlier today. LOL |
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