This is my solution. Keep it simple stupid 😀.
Under 2 Ohm load, the input transistor dissipate less than 270mW peak.
Still , those sc/sa "robust devices" would ensure decades of abuse.
I want to build amps that just have to be recapped every 20 years.
NO B$ !!
OS
Being from the speaker side of things I would avoid any speaker that was dipping into the 2ohm range, that is asking for damage to most amplifiers, we are not building these amplifiers for cars are we? I consider any speaker load under about 3.6ohm as a problematic load for any amplifier.
Of course not 🙂. I would like to drive 8 Ohm speaker. Lower distortion.
But, I think when we accidentally connect to low impedance load, only fuse will burn, not transistors in IPS.
Sometime party person (that what OS call them), may drive amp into 2 Ohm speaker 😱.
I you ran the slew-5 with 60-70V/MJL21193/4 ,A 1R load would be nothing.
Uncle carlos (DX) "lit-up" Ni-chrome toaster wires with a EF2 amplifier output -
EF3 would be easy !!
PS - a reasonable speaker might dip to 4R (8R speaker) , my daytons (8R) , dip to 3.6R above and below port
resonance. The badgers don't feel a thing - objects fall to the floor ... TOO much SPL !!
OS
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NI-chrome,
Are we trying for a dead short here! I would sure question a speaker rated at 8 ohm getting down into the low 3's as being deceptively marked. I would typically expect a double hump in the impedance rising on both sides of the port tuning, not dropping below the impedance minimum and rising at a rate going towards the high frequency point.
Are you adding some dead short protection to your amplifier circuit?
Are we trying for a dead short here! I would sure question a speaker rated at 8 ohm getting down into the low 3's as being deceptively marked. I would typically expect a double hump in the impedance rising on both sides of the port tuning, not dropping below the impedance minimum and rising at a rate going towards the high frequency point.
Are you adding some dead short protection to your amplifier circuit?
Nope , I'm running a dayton 8" (designer series)pair , I can "flat out" run the badger full power and not blow them . The Imp. curve comes close to 4R
at 30 and 55Hz ... The amp/speakers just level the room ... ALL objects fall.
45 HZ is brutal (acoustically) ... shakes the window panes.
for an 8" - I'm impressed with the dayton drivers. My 10" sub barely
matches the dayton's .... they really don't need subwoofer "backup".
I want a ported dayton 12" sub with the 5-pair slew - "war zone" 😀
PS- http://www.parts-express.com/dayton-audio-um12-22-12-ultimax-dvc-subwoofer-2-ohms-per-coil--295-512
plus a 500Va 50-0-50V trafo/40Kuf ...
And my slew 5-pair, damn earthquake !!
OS
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OS, if I want to run the pre-driver "hotter", the heat sink is separated from driver heat sink or not?
and don't even get him started on the curve tracers ....
jeez, richard is there ANYTHING you don't have out there?
😛
mlloyd1
jeez, richard is there ANYTHING you don't have out there?
😛
mlloyd1
Not sure what to suggest tbh. I read all your later posts too. Its one of those things where you need the PC in front of you really, to see what is going on.
Mooly,
Thanks I joined the ltspice group on Yahoo and the help I am getting is the same I have found myself. I am wondering if they messed something up as they just updated the program two days ago, perhaps a flaw in the program is what I am seeing. I give up for tonight. I have tried everything that makes any sense. Doesn't want to unzip the program files but has installed the libraries. Always something with Windows.
Thanks I joined the ltspice group on Yahoo and the help I am getting is the same I have found myself. I am wondering if they messed something up as they just updated the program two days ago, perhaps a flaw in the program is what I am seeing. I give up for tonight. I have tried everything that makes any sense. Doesn't want to unzip the program files but has installed the libraries. Always something with Windows.
If I dont have it right now, its because i used to have it and didnt need it and got rid of it; I used to have a lot more RF equipment. I have pc curve tracer and stand-alone curve tracer and several other small transistor testers.
I've been a test equipment junky for a long time.
Thx-RNMarsh
LTSpice gets updated every few days. That is just the component library as new devices appear, the basic program itself is unchanged.
It should install in seconds. Are you using the official site and link ?
Linear Technology - Design Simulation and Device Models
If you look in C:\program files (just type that in the run box bottom left) you should see something like x86 programme files. They are the 32 bit installs which includes LTspice. (I'm on Vista at the moment but its similar)
Look for LTC. Click it and it should have all these components. Right click the "scad3" item and make a shortcut from it. Now right click the shortcut and give it administrator properties (with Vista I didn't need too).
Attachments
Mooly,
I finally got smart and though I wasn't getting any warning and was trying to install as the administrator I thought about my virus protection and that was what it was all along. My Trend Micro was letting the program partially install but each time it got to unzipping the actual program files it was blocking it. Temporarily turned it off and it went right in. I can see the ltspice window now. All I have to do now is start to figure out how to use it. I see the different devices like resistor and caps and I guess you have to build the circuit just like in my other cad programs. I'll have to see if I can build one of Ostripper's circuits but I won't know how to use his devices until I get much farther into the whole mess. Thanks for trying to help, I should have suspected the virus checker earlier.
I finally got smart and though I wasn't getting any warning and was trying to install as the administrator I thought about my virus protection and that was what it was all along. My Trend Micro was letting the program partially install but each time it got to unzipping the actual program files it was blocking it. Temporarily turned it off and it went right in. I can see the ltspice window now. All I have to do now is start to figure out how to use it. I see the different devices like resistor and caps and I guess you have to build the circuit just like in my other cad programs. I'll have to see if I can build one of Ostripper's circuits but I won't know how to use his devices until I get much farther into the whole mess. Thanks for trying to help, I should have suspected the virus checker earlier.
Ahhh... Trend. I had that on my Dell but ditched it when I did a clean install.
Do you have Bob Cordells book ? That really is worth its weight in gold in using LTSpice. Until I read that I just stared at the screen and hadn't a clue how to use it.
If you are stuck on anything and want to start a thread on using LTspice then I can give you some pointers. I learnt the hard way, it took me weeks to figure out how to include models and so on 🙂 Once you know the basics it suddenly all makes more sense.
Do you have Bob Cordells book ? That really is worth its weight in gold in using LTSpice. Until I read that I just stared at the screen and hadn't a clue how to use it.
If you are stuck on anything and want to start a thread on using LTspice then I can give you some pointers. I learnt the hard way, it took me weeks to figure out how to include models and so on 🙂 Once you know the basics it suddenly all makes more sense.
Molly,
Yes I have Bob's book. I forgot that was in the book. I'll start reading it tomorrow. I made a line and added a ground symbol and then a resistor and couldn't figure out how to rotate the symbol. That was enough for tonight, it is almost 2:30 am. time to call it a night. But many thanks for helping out.
Steven
Yes I have Bob's book. I forgot that was in the book. I'll start reading it tomorrow. I made a line and added a ground symbol and then a resistor and couldn't figure out how to rotate the symbol. That was enough for tonight, it is almost 2:30 am. time to call it a night. But many thanks for helping out.
Steven
Your welcome 🙂
(yes, read all the sections on LTSpice in Bobs book and work through the examples. One tip once you have it up and running... if you occasionally type .raw into W7's search box you wll locate remnant files of sim data that have not been deleted. That happens if you save a file under a different name etc. They build up and can be large. Follow Bob's recommend to set them to auto delete... but do a manual check occasionally)
(yes, read all the sections on LTSpice in Bobs book and work through the examples. One tip once you have it up and running... if you occasionally type .raw into W7's search box you wll locate remnant files of sim data that have not been deleted. That happens if you save a file under a different name etc. They build up and can be large. Follow Bob's recommend to set them to auto delete... but do a manual check occasionally)
