Jesperino,
1) My PC is in storage until July 1 so can't do a sim, but the RCF LF18X451 specs look similar enough to the BC18SW115 that it sounds like you have made an input error. I would not think there would be anything near a 21 dB range in the frequency response.
2)Based on #1 can't advise any broadband EQ.
3) I'd try the subs and tops in two of the 5 meter wide wall room corners.
Wooow
Thanks for your answers guys 🙂
That sim looks better than i dared to dream about!
(After the one i made OMG)
Im gonna do some measurements on thursday.
Thanks for your answers guys 🙂
That sim looks better than i dared to dream about!
(After the one i made OMG)
Im gonna do some measurements on thursday.
In the interest of full disclosure, there is some debate about how accurate the sim is. IIRC there are at least 3 versions of HR data for KS and worst case the low corner might not be what it appears. That said, your driver looks like a winner and matches up with the best of drivers I have in HR. Art will remind us that measurements trump sim so best of luck!
2 of those in a room that size is pretty crazy to me! ENJOY
2 of those in a room that size is pretty crazy to me! ENJOY
It went really well everything.
The measurement is not as pretty as on the SIM
But it still looks pretty good with just a few minor peaks and dips.
Sounded really really good though, but nothing to extreme.
Was powered by a QSC 4050a 8ohm load connected 1 in each channel.
So i think it was only powered by 850 watts.
So i guess i have to try and connect in parallel and put the AMP in bridge mode
to get 4000 watts in 4 ohm.
The measurement is not as pretty as on the SIM
But it still looks pretty good with just a few minor peaks and dips.
Sounded really really good though, but nothing to extreme.
Was powered by a QSC 4050a 8ohm load connected 1 in each channel.
So i think it was only powered by 850 watts.
So i guess i have to try and connect in parallel and put the AMP in bridge mode
to get 4000 watts in 4 ohm.
Did you measure in that small room? To compare/measure accurately you would need to be outside and not near any buildings or structures since room modes and reflections will affect the results.
Yeah it was inside in the small room in the corner
Not a precise measurement at all
But still the result was pretty good i would say
Gonna try this week in a more open area when my friend have time.
You think i can easy try in parallel/bridge mode
I dont have much experience with these things
But it should be OK right?
Not a precise measurement at all
But still the result was pretty good i would say
Gonna try this week in a more open area when my friend have time.
You think i can easy try in parallel/bridge mode
I dont have much experience with these things
But it should be OK right?
4kW in that room is over the top even to a guy like me, but I think you could do it. A quick sim shows 2 corner loaded KS at 1800w (20mm peak to peak) exceeding 145db...
Do remember TH need high passed below passband. The built in 30hz in 4050 should do nicely. Also, setting up a limiter would be advised and I would do some room correction via EQ if you are not already.
Do remember TH need high passed below passband. The built in 30hz in 4050 should do nicely. Also, setting up a limiter would be advised and I would do some room correction via EQ if you are not already.
Hehe
Tbh i have no idea how much 4KW sounds in real life in a small room
I waas more thinking that if the drivers can handle it and the amp can deliver it...
Then why not try it? Can always turn down if its to much.
The thing is... The guy from where i borrow the equipment.
(AMP, XOVER, EQ & Limiter/Compressor)(and yes, using the build in 30hz lowcut)
He doesnt really seem to excited that we put it in bridge mode.
And im not really sure why?
Seems like he think that theres NO WAY that the drivers can handle that much amount of power. He thinks the specs are exaggerated.
I been trying to talk to him about it, but its not that easy
He only speaks spanish and my spanish is not that brilliant to talk about the kind of complexe technical things when i myself is just in the process of learning it.
I even wrote directly to RCF yesterday to ask>
Hello
I just recently started building some subs
I am totally new when it comes to this world of watts and amps etc...
Anyways... I ended up buying 2 of these 18" Drivers
RCF LF18X451
RCF - LF18X451
And it seems like they can handle A LOT of power :O hehe
So i been trying to Find out how much watts i can safely feed to these drivers...
And it seems like everybody have very different opinions about it...
Some people say MAX 1800W
Some people say MAX 3600W
And even some people have a really hard time to believe that its even possible that it can handle that much power...
I tried this weekend with this AMP QSC 4050
But it gives only 850watts pr channel at 8 ohm load
So i was thinking to put it in bridge mode and the speakers in parallel
In that way i would have 4000 watts at a 4ohm load
If i understand this correct this shouldnt be a problem no?
Or what do you recommend??
Thanks
Best regards
Jesper
RCF reply>
Hi Jesper, yes, you are correct. If you put it in bridge mode and the speakers in parallel, it is not going to be a problem.
Good luck and best regards,
the RCF Team
As mentioned earlier it sounded great the other day
But would still like a bit more power
So im just looking for a safe way to get the most out of what i have.
Thanks a lot for your inputs
Much appreciated
Tbh i have no idea how much 4KW sounds in real life in a small room
I waas more thinking that if the drivers can handle it and the amp can deliver it...
Then why not try it? Can always turn down if its to much.
The thing is... The guy from where i borrow the equipment.
(AMP, XOVER, EQ & Limiter/Compressor)(and yes, using the build in 30hz lowcut)
He doesnt really seem to excited that we put it in bridge mode.
And im not really sure why?
Seems like he think that theres NO WAY that the drivers can handle that much amount of power. He thinks the specs are exaggerated.
I been trying to talk to him about it, but its not that easy
He only speaks spanish and my spanish is not that brilliant to talk about the kind of complexe technical things when i myself is just in the process of learning it.
I even wrote directly to RCF yesterday to ask>
Hello
I just recently started building some subs
I am totally new when it comes to this world of watts and amps etc...
Anyways... I ended up buying 2 of these 18" Drivers
RCF LF18X451
RCF - LF18X451
And it seems like they can handle A LOT of power :O hehe
So i been trying to Find out how much watts i can safely feed to these drivers...
And it seems like everybody have very different opinions about it...
Some people say MAX 1800W
Some people say MAX 3600W
And even some people have a really hard time to believe that its even possible that it can handle that much power...
I tried this weekend with this AMP QSC 4050
But it gives only 850watts pr channel at 8 ohm load
So i was thinking to put it in bridge mode and the speakers in parallel
In that way i would have 4000 watts at a 4ohm load
If i understand this correct this shouldnt be a problem no?
Or what do you recommend??
Thanks
Best regards
Jesper
RCF reply>
Hi Jesper, yes, you are correct. If you put it in bridge mode and the speakers in parallel, it is not going to be a problem.
Good luck and best regards,
the RCF Team
As mentioned earlier it sounded great the other day
But would still like a bit more power
So im just looking for a safe way to get the most out of what i have.
Thanks a lot for your inputs
Much appreciated
I think you're headed in the right direction going bridged. Make sure your power is good. In the states you'd be pushing things with 120VAC but might be fine for you with 220VAC. I used to run a 3000W amp bridged on my subs and it got loud OUTSIDE. 😀
Jesper,
The short answer is you won't hear much difference, only about 3 dB (or less) difference between 850 and 2000 watts per driver, as there will be some thermal compression with additional power.
To sound twice as loud at 40 Hz requires about a 5 dB increase in SPL, which would require more than a 6 dB increase in power (850 to 3400) - too much average power if your program material does not have wide dynamics.
To sound twice as loud at 1000 Hz requires about a 10 dB increase in SPL.
Art
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There is still a lot to learn about all these topics...
I realize there is the same difference (20DB) between 10w and 1.000w as there is between 1.000w and 10.000
But is there any good reason then for having drivers that can handle 1800w/3600w compared to a driver that can handle 1000w?
(Besides being way more expensive and need way more expensive AMP Power)
If its not for the SPL would it be for clearity? Xmax? Or just because its a better build that supposedly will last longer?
As i understood its best for the driver if you feed it aprox x 1.5 the power to really make it shine.
So in this case with this driver 1.800w X 1.5 = 2.700w
So when i have 2 of these drivers seems like it would be a good idea to feed them 5.000w
Or what would be the best recommendation to make these drivers play the best and most powerful they can?
I realize there is the same difference (20DB) between 10w and 1.000w as there is between 1.000w and 10.000
But is there any good reason then for having drivers that can handle 1800w/3600w compared to a driver that can handle 1000w?
(Besides being way more expensive and need way more expensive AMP Power)
If its not for the SPL would it be for clearity? Xmax? Or just because its a better build that supposedly will last longer?
As i understood its best for the driver if you feed it aprox x 1.5 the power to really make it shine.
So in this case with this driver 1.800w X 1.5 = 2.700w
So when i have 2 of these drivers seems like it would be a good idea to feed them 5.000w
Or what would be the best recommendation to make these drivers play the best and most powerful they can?
How much you can feed the drivers depends on the crest factor of the music signal you are feeding them with.
What music do you intend to use on them?
How the cone can hold up to the pressures built up in the cab is also of importance, however rcf seem to claim the driver holds up well in high pressure horns and I have no reason to doubt it. I think around 900-1000w long term limiter setting would be a good starting point with a 30 hz 24dB/oct hpf and keep an eye on magnet temperature. You can probably almost fry eggs on the magnet before it gets dangerous but rcf might know the temperature limit on the magnet before glue and such things start to melt.
That sim is indeed impressive, seem to dig a few hz lower than b&c equivalents but play a dB or two lower.
Looks like a really nice heavy duty driver! Please report how they perform
What music do you intend to use on them?
How the cone can hold up to the pressures built up in the cab is also of importance, however rcf seem to claim the driver holds up well in high pressure horns and I have no reason to doubt it. I think around 900-1000w long term limiter setting would be a good starting point with a 30 hz 24dB/oct hpf and keep an eye on magnet temperature. You can probably almost fry eggs on the magnet before it gets dangerous but rcf might know the temperature limit on the magnet before glue and such things start to melt.
That sim is indeed impressive, seem to dig a few hz lower than b&c equivalents but play a dB or two lower.
Looks like a really nice heavy duty driver! Please report how they perform
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Hey guys
I managed to have another test
Same AMP and equipment
But in another room... (More or less same size 5mX7m)
A very important detail about the other room where i had the first test.
It was NOT rectangular shaped.
It turned out to be more like 2 rooms connected that together would form an L/T kind of shape.
And there was extreme bass cancellation almost everywhere besides the corners. But as the party went on and the room was full of people i didnt sense the cancellation that strong though.
In the new room where i tested it i could hear, judge and feel the bass much better.
And i have to say the sound is super clear, you can really hear the different bass notes and there is no boomy mud. Really impressive.
Cant remember when is last time i heard such a clear bass tbh.
But also because of that im sure the drivers can handle much more than what i could give in the test before AMP started clipping.
Im looking at some kickbins that would fit perfect on top of the keystone.
Im looking at some of these at the moment:
MKB/MKH-230
FSV15
CUBO KICK 15
SV186 BPH
2Qh KICK
Anything else i should check out?
As mentioned... Looking for something that fits on top of the Keystone
Would probably like it to cover from 80hz to 150hz/180hz.
I managed to have another test
Same AMP and equipment
But in another room... (More or less same size 5mX7m)
A very important detail about the other room where i had the first test.
It was NOT rectangular shaped.
It turned out to be more like 2 rooms connected that together would form an L/T kind of shape.
And there was extreme bass cancellation almost everywhere besides the corners. But as the party went on and the room was full of people i didnt sense the cancellation that strong though.
In the new room where i tested it i could hear, judge and feel the bass much better.
And i have to say the sound is super clear, you can really hear the different bass notes and there is no boomy mud. Really impressive.
Cant remember when is last time i heard such a clear bass tbh.
But also because of that im sure the drivers can handle much more than what i could give in the test before AMP started clipping.
Im looking at some kickbins that would fit perfect on top of the keystone.
Im looking at some of these at the moment:
MKB/MKH-230
FSV15
CUBO KICK 15
SV186 BPH
2Qh KICK
Anything else i should check out?
As mentioned... Looking for something that fits on top of the Keystone
Would probably like it to cover from 80hz to 150hz/180hz.
Speakerplans.com
The HD15 is a pretty common kickbin. Very easy to make doubles of them if you're so inclined
The HD15 is a pretty common kickbin. Very easy to make doubles of them if you're so inclined
Personally I don't see the reason for a kick bin, the cabs play very good up to around 110 hz at least IMO, get a strong top and leave the kick out is my recommendation.
I've used them with kling Freitag t9 which according to them have a -3dB at 130 hz and I don't feel I miss anything very important. You might be looking for another sound than me tho
Gonna use my keystones outside for the first time this Saturday, will be interesting to see how they perform there!
I've used them with kling Freitag t9 which according to them have a -3dB at 130 hz and I don't feel I miss anything very important. You might be looking for another sound than me tho
Gonna use my keystones outside for the first time this Saturday, will be interesting to see how they perform there!
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Yes i also been looking at USB (singles) ES18 BPH and of course HD15
I really like HD15, but i wouldnt mind trying one of the other designs i mentioned.
But tbh i think HD15 is a potential winner.
OSSE i havent tried the keystone above 100hz yet
Maybe thats why i feel there is missing some kick.
Now i split them apart to put glue... So it will take a little while before i can use them again.
How many Keystones you have?
By the way
In regards to choosing a kick bin design
I am also limited to what drivers i can easy get here in Lima.
So far i have these RCF available>
RCF LF15X401 1500w/3000w 2 X 632 USD
RCF MB15X351 700w/1500w 2 X 538 USD
RCF L15S801 700w/1500w 2 X 460 USD
RCF LF12X401 1000w/2000w 2 X 540 USD
RCF L12L750 350w/700w 2 X 500 USD
I really like HD15, but i wouldnt mind trying one of the other designs i mentioned.
But tbh i think HD15 is a potential winner.
OSSE i havent tried the keystone above 100hz yet
Maybe thats why i feel there is missing some kick.
Now i split them apart to put glue... So it will take a little while before i can use them again.
How many Keystones you have?
By the way
In regards to choosing a kick bin design
I am also limited to what drivers i can easy get here in Lima.
So far i have these RCF available>
RCF LF15X401 1500w/3000w 2 X 632 USD
RCF MB15X351 700w/1500w 2 X 538 USD
RCF L15S801 700w/1500w 2 X 460 USD
RCF LF12X401 1000w/2000w 2 X 540 USD
RCF L12L750 350w/700w 2 X 500 USD
I've got two now, crossing them at 106hz. First I had a lot of leaks around my inserted wheels which made them sound strange above 75 but when I got it sorted and raised the xover to 106 they really came alive.
Where is the maximum you have crossed them? How are the rcf driver sounding in them? I hope it holds up for you
Where is the maximum you have crossed them? How are the rcf driver sounding in them? I hope it holds up for you
I havent really had the posibilities to play much around with equipment and xover settings because the equipment is not mine.
But just made standard cut off 30hz > 100hz
Im really tempted to buy iNuke DSP 12000 /That supposedly delivers sonething near 1700w 8ohm/3400w 4ohm/6000w 2ohm pr channel.
Here in Peru it cost only 650USD, way cheaper than both US and EU.
And the iNuke 6000 DSP cost 500 USD.
If ft survives 20 parties, it have all ready paid itself compared to the price of renting AMP/xover/limiter/eq etc.
But i will definitely try to cut it a little higher to see if i kan get some kick punch out of the beasts.
In the measurement we did with pink noise it actually have a pretty decent response up to 150hz before it starts to fade out.
Before we build the keystone we tried out with a Super Bass Horn
It was our first build ever and it didnt turn out that well tbh
Really bad wood, bad cuts a few mistakes and leaks from the box and so on.
Response was really bad with extreme dips in 50hz and 70hz and huge peak at 80hz lol
So these 2 keystones is first time we ever tried build anything that actually sounds... And sounds good hehe. So i dont have to much to compare with, but i think the keystone and the RCF LF18X451 is a really great combination.
Im sure i just need some serious AMP power to really get some juice out of them.
The QSC 4050 i used is apparently a super old antique model
Cant find the specs of it, but its a completely different AMP than the one there is on the market now.
What AMP and Drivers do you use in your keystones?
Cant wait to finish with glue and paint so we can start use them again.
But just made standard cut off 30hz > 100hz
Im really tempted to buy iNuke DSP 12000 /That supposedly delivers sonething near 1700w 8ohm/3400w 4ohm/6000w 2ohm pr channel.
Here in Peru it cost only 650USD, way cheaper than both US and EU.
And the iNuke 6000 DSP cost 500 USD.
If ft survives 20 parties, it have all ready paid itself compared to the price of renting AMP/xover/limiter/eq etc.
But i will definitely try to cut it a little higher to see if i kan get some kick punch out of the beasts.
In the measurement we did with pink noise it actually have a pretty decent response up to 150hz before it starts to fade out.
Before we build the keystone we tried out with a Super Bass Horn
It was our first build ever and it didnt turn out that well tbh
Really bad wood, bad cuts a few mistakes and leaks from the box and so on.
Response was really bad with extreme dips in 50hz and 70hz and huge peak at 80hz lol
So these 2 keystones is first time we ever tried build anything that actually sounds... And sounds good hehe. So i dont have to much to compare with, but i think the keystone and the RCF LF18X451 is a really great combination.
Im sure i just need some serious AMP power to really get some juice out of them.
The QSC 4050 i used is apparently a super old antique model
Cant find the specs of it, but its a completely different AMP than the one there is on the market now.
What AMP and Drivers do you use in your keystones?
Cant wait to finish with glue and paint so we can start use them again.
I'm using 18sw115 8 ohm models in mine, paired with a SAE pxm 1450 amp which delivers 1450w in 8 ohm for 5 seconds 40 hz... very capable sub amp
If you have 8 ohm model drivers you will need some very serious power for them, minimum 1000w at 8 ohm is my recommendation.
I think it should have OK kick with 100 hz aswell
If you have 8 ohm model drivers you will need some very serious power for them, minimum 1000w at 8 ohm is my recommendation.
I think it should have OK kick with 100 hz aswell