Eve-nin
Hi,
I've downloaded WinLsd 0.50a7. Er, does anybody want to tell me what to do, it looks even more complicated when I know I got to use it properly. I downloaded it ages ago, but only played with it. I have a list of parameters and I'm going to assume I've got to put the driver into the database. So I'll get on with that.
Cheers Mike
Hi,
I've downloaded WinLsd 0.50a7. Er, does anybody want to tell me what to do, it looks even more complicated when I know I got to use it properly. I downloaded it ages ago, but only played with it. I have a list of parameters and I'm going to assume I've got to put the driver into the database. So I'll get on with that.
Cheers Mike
Back home after a weekend away. Mike I think your power supply and amp is not up to the job and it's clipping, making the noise. An advertised 100w amp is more like 50w in reality and your power supply will be struggling to keep up with even that.
When Pinkmouse was on about the gain of the LT he means don't try to EQ down so far in the frequency range, e.g. just try for 30Hz. Like I suggested in the first place
When Pinkmouse was on about the gain of the LT he means don't try to EQ down so far in the frequency range, e.g. just try for 30Hz. Like I suggested in the first place
Hello Sir
...OH WHAT AM I TO DO WITH ME??
I just wanted to get down low with my audio, I get such a buzz from a real deep bass. I was greedy and went for 20Hz. What can I say, I'm a Bass Head. If I had a big enough amp/powersupply can I stay at 20Hz? I don't want to dismantle my new toy. I just love its potentcy.
richie000boy, bless you for helping me, I want to build an amp for it and that will be my next project. Does this mean I can't find out how to measure what I have created?
Anders, I don't have these parameters, so I guess measuring is outta the question?
Cheers Mike
Was Big Brother fixed?(Sorry)
...OH WHAT AM I TO DO WITH ME??
I just wanted to get down low with my audio, I get such a buzz from a real deep bass. I was greedy and went for 20Hz. What can I say, I'm a Bass Head. If I had a big enough amp/powersupply can I stay at 20Hz? I don't want to dismantle my new toy. I just love its potentcy.
richie000boy, bless you for helping me, I want to build an amp for it and that will be my next project. Does this mean I can't find out how to measure what I have created?
Anders, I don't have these parameters, so I guess measuring is outta the question?
Cheers Mike
Was Big Brother fixed?(Sorry)
Ha ha!
Yeah, but I've got the gain turned right down on the amp. If I turn it up, things get really physical. I've got the little screwdriver pot turned half a notch, I'm playing Leftfield at the mo and its nice. But then, its late at night, earlier I was playing some and that squeaky noise was there again!
I just hope the system lasts long enough while I have a go at amp building.
Cheers Mike
Yeah, but I've got the gain turned right down on the amp. If I turn it up, things get really physical. I've got the little screwdriver pot turned half a notch, I'm playing Leftfield at the mo and its nice. But then, its late at night, earlier I was playing some and that squeaky noise was there again!
I just hope the system lasts long enough while I have a go at amp building.
Cheers Mike
mikee55,
Not necessary so
Sd, the most important here is easy.
Sd=(d^2*pi)/4 where d is diameter of the cone, half of surround included.
X-max, if you can see the coil through the vents in your pic #2, just gently press the cone until coil just dissapear in gap, required travel from resting position is approx X-max.
Pe, max thermal power limit, important if you want to know just that. Usually grossly exagurrated on cheap drivers.
Not necessary so
Sd, the most important here is easy.
Sd=(d^2*pi)/4 where d is diameter of the cone, half of surround included.
X-max, if you can see the coil through the vents in your pic #2, just gently press the cone until coil just dissapear in gap, required travel from resting position is approx X-max.
Pe, max thermal power limit, important if you want to know just that. Usually grossly exagurrated on cheap drivers.
Ha ha ha
The missus starts her new job tommorrow so I'll be playing with various styles. At the mo I'm playing my k.d.lang invincible summer DVD Audio. I have Intervideo WinDvd Platinum version 6, it can play Dvd Audio if you have a Creative soundcard.
So 24bit/96 sounds good, the missus told me to turn it down but I argued that we are speaking, not shouting and so I havn't turned it down.
Its mad.
Could you explain what would happen if I installed a bigger amp, not technicaly but acousticly? I've only ever used these sized amps.Obviously I don't want to be blasting it out, I have a 24 db crossover inbetween the Input mixer and Transform, richie000boy told me to make 12db variable 12db fixed (40Hz) so it could be tuned up to my Mordaunt Short MS40's(70Hz ports closed), but I've found that I need to filter down low or Bass starts to buzz/boom and is really crude, even now a bass guitar is booming a little. I have nothing to reference it with, so I usually listen to music that has a bass that starts high in frequency then drops and then the speaker has to be able to follow it. Chemical Brothers have a good track for that, can't remember the name of it. I'll dig it out tommorow.
Cheers Mike
The missus starts her new job tommorrow so I'll be playing with various styles. At the mo I'm playing my k.d.lang invincible summer DVD Audio. I have Intervideo WinDvd Platinum version 6, it can play Dvd Audio if you have a Creative soundcard.
So 24bit/96 sounds good, the missus told me to turn it down but I argued that we are speaking, not shouting and so I havn't turned it down.
Its mad.
Could you explain what would happen if I installed a bigger amp, not technicaly but acousticly? I've only ever used these sized amps.Obviously I don't want to be blasting it out, I have a 24 db crossover inbetween the Input mixer and Transform, richie000boy told me to make 12db variable 12db fixed (40Hz) so it could be tuned up to my Mordaunt Short MS40's(70Hz ports closed), but I've found that I need to filter down low or Bass starts to buzz/boom and is really crude, even now a bass guitar is booming a little. I have nothing to reference it with, so I usually listen to music that has a bass that starts high in frequency then drops and then the speaker has to be able to follow it. Chemical Brothers have a good track for that, can't remember the name of it. I'll dig it out tommorow.
Cheers Mike
Mike it would be nice to find out the parameters 4fun is telling you, but you can manage without.
As Pinkmouse has said the PSU is preventing you from real damage.
When you get a man enough amp the sound will be tighter and more controlled, as well as hitting deeper. If you are definitely going to put a new amp in then you can leave the LT as it is and see how the speaker copes with the new amp.
As Pinkmouse has said the PSU is preventing you from real damage.
When you get a man enough amp the sound will be tighter and more controlled, as well as hitting deeper. If you are definitely going to put a new amp in then you can leave the LT as it is and see how the speaker copes with the new amp.
Low volts
Hi all, just stuck meter on rails, 9.8 volts average also the LT runs off this supply as well at appx +/- 9.7 volts appx whilst playing Pink Floyd Dark Side of The Moon.( oops). Wasn't playing low stuff either. If the power supply is drooping that much, does it mean its not regulated, just out of curiosity?
Cheers Mike
Hi all, just stuck meter on rails, 9.8 volts average also the LT runs off this supply as well at appx +/- 9.7 volts appx whilst playing Pink Floyd Dark Side of The Moon.( oops). Wasn't playing low stuff either. If the power supply is drooping that much, does it mean its not regulated, just out of curiosity?
Cheers Mike
Hi,
You mean constant low voltage?
The supply may take feedback from one of the other voltages, so 12V may not be directly regulated.
If no load on the rail with feedback the 12V may suffer if loaded alone.
Newer PC supplies usually have feedback on 12V, as all load is there today.
But as pointed out earlier, your supply is probably to weak.
You mean constant low voltage?
The supply may take feedback from one of the other voltages, so 12V may not be directly regulated.
If no load on the rail with feedback the 12V may suffer if loaded alone.
Newer PC supplies usually have feedback on 12V, as all load is there today.
But as pointed out earlier, your supply is probably to weak.
With LT's you have to resist the temptation to go for loads of extension if you have limited power and Vd. Remember that every time you add 3db of boost you double your power requirements, if you try to get mega low output it gets out of hand quickly 
Looking at the plot you posted, assuming you are playing everything above ~50Hz at 20W...
By 40Hz you have 3db's of boost, 40w amp required,
36Hz 6db, 80w required,
31Hz 9db, 160w required,
26Hz 12db, 320w required...
When you get to 20Hz you have 15db of boost, requiring 640w to play 20Hz at the same level as 50Hz with just 25w, not to mention your cone will be slapping you in the face from the other side of the room
What size is your room? It's good practice to design a sub based around your room gain, but to do this you need some measurement gear. Do a Google search for 'RoomEQ Wizard', it's a freeware software tool that uses your soundcard and a mic to take measurements.
A quick and dirty method I use to do an initial estimate of room gain is to do a nearfield measurement of a speaker (nearfield is at low level with the mic very close the the cone to prevent room/baffle effects), it doesn't matter how it measures so long as you have some 20Hz output.
Next put the mic in the listening position and the speaker where it's likely to be placed and take a measurement, keeping the levels of the upper frequencies similar in level.
Now you can compare the two plots, you should find that the second measurement appears to go lower. Compare relative output of the two measurements, for example at 20Hz, 30Hz, 40Hz and 50Hz ect. From there you can work out how your sub needs to roll off to match the room.
Using this method I get flat output to 10Hz in my room, despite having a sub with a 30Hz f3 and 0.5Q rolloff slope
Looking at the plot you posted, assuming you are playing everything above ~50Hz at 20W...
By 40Hz you have 3db's of boost, 40w amp required,
36Hz 6db, 80w required,
31Hz 9db, 160w required,
26Hz 12db, 320w required...
When you get to 20Hz you have 15db of boost, requiring 640w to play 20Hz at the same level as 50Hz with just 25w, not to mention your cone will be slapping you in the face from the other side of the room
What size is your room? It's good practice to design a sub based around your room gain, but to do this you need some measurement gear. Do a Google search for 'RoomEQ Wizard', it's a freeware software tool that uses your soundcard and a mic to take measurements.
A quick and dirty method I use to do an initial estimate of room gain is to do a nearfield measurement of a speaker (nearfield is at low level with the mic very close the the cone to prevent room/baffle effects), it doesn't matter how it measures so long as you have some 20Hz output.
Next put the mic in the listening position and the speaker where it's likely to be placed and take a measurement, keeping the levels of the upper frequencies similar in level.
Now you can compare the two plots, you should find that the second measurement appears to go lower. Compare relative output of the two measurements, for example at 20Hz, 30Hz, 40Hz and 50Hz ect. From there you can work out how your sub needs to roll off to match the room.
Using this method I get flat output to 10Hz in my room, despite having a sub with a 30Hz f3 and 0.5Q rolloff slope
Hello
FullThrottleRic, hello.
I usually listen at low volumes (except when driving) approx 1 watt would be more realistic, but from the sub point of view, I was after just being able to reach down as low as I can. Sometimes I'll have a mad session with the volume, but then I think hifi goes outta the window and I'm listening for the fun of it. I recently had the amp out of a pair of PC speakers and drove a pair of 12" 3 way Goodmans loudspeakers. I reckon that to have been 3 to 5 watts, and they filled my 3m x 4m lounge. And yet, I thought you'd need loads of power to get what I got with this little amp. I suprised a few people with it.
4fun,hello.
If I unscrew my driver anymore, I gonna need bigger screws. I must buy some T-nuts and bolts, when I do I'll have a look.
richie000boy, hello sir.
Hows the amp design coming along, sir? I'm saving some pennies now. What size Transformer are we thinking, please?
Cheers Guys
FullThrottleRic, hello.
I usually listen at low volumes (except when driving) approx 1 watt would be more realistic, but from the sub point of view, I was after just being able to reach down as low as I can. Sometimes I'll have a mad session with the volume, but then I think hifi goes outta the window and I'm listening for the fun of it. I recently had the amp out of a pair of PC speakers and drove a pair of 12" 3 way Goodmans loudspeakers. I reckon that to have been 3 to 5 watts, and they filled my 3m x 4m lounge. And yet, I thought you'd need loads of power to get what I got with this little amp. I suprised a few people with it.
4fun,hello.
If I unscrew my driver anymore, I gonna need bigger screws. I must buy some T-nuts and bolts, when I do I'll have a look.
richie000boy, hello sir.
Hows the amp design coming along, sir? I'm saving some pennies now. What size Transformer are we thinking, please?
Cheers Guys
This is the prototype n-channel MOSFET amp. With IRFP250 devices it spits out 150w. The final design will feature a slight rejigging of a couple of parts to space them better, but look basically like this.
And the PSU looks like this with 10000uF 63V caps.
All my projects are designed to be easy to build, i.e. decent size tracks and pads and sensible component spacings.
For a 150w amp I would recommend a 300VA transformer. But really anything from 180VA to 300VA would do.
An externally hosted image should be here but it was not working when we last tested it.
And the PSU looks like this with 10000uF 63V caps.
An externally hosted image should be here but it was not working when we last tested it.
All my projects are designed to be easy to build, i.e. decent size tracks and pads and sensible component spacings.
For a 150w amp I would recommend a 300VA transformer. But really anything from 180VA to 300VA would do.
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