Hi,
maybe you can use a schematic of http://www.aussieamplifiers.com ??
He (Anthony Holton) has built an amplifier using 20 IRFP's that gives you about 1200W RMS into 4 Ohms (he measured 1600W RMS into 4 Ohms, but then you need a REALLY stable supply!!).
You could use that?
And why all those nonsense about needing high power? There are lots of car-amplifiers that have over 2000W RMS!!!! If he needs 1500W then he needs 1500W!...
Grtz, Joris
maybe you can use a schematic of http://www.aussieamplifiers.com ??
He (Anthony Holton) has built an amplifier using 20 IRFP's that gives you about 1200W RMS into 4 Ohms (he measured 1600W RMS into 4 Ohms, but then you need a REALLY stable supply!!).
You could use that?
And why all those nonsense about needing high power? There are lots of car-amplifiers that have over 2000W RMS!!!! If he needs 1500W then he needs 1500W!...
Grtz, Joris
That's exactly the point where we don't agree.
Most semi-professional commercial PA stuff is overrated. A power amplifier with a single 800 VA transformer inside will never deliver 2 x 1000W RMS. So I guess it is about the same whether you buy this overrated device or build a 2x250W DIY amp.
I've built several PA systems with a total 3 kVA worth of transformers (total RMS output power maybe around 1.2 kW), and running at anything near but max power they sounded louder and cleaner than commercial systems rated at 20 kW in exactly the same room.
SPL depends more on speaker efficiency than amplifier power. Better build a higher quality lower power amp and get higher efficiency speaker. Not always true, but definitely for PA and DJing.
A 2000W car amplifier doesn't make any sense. Really.
You need to draw or find a schematic that will suit your power needs.
For 1500 Wrms @ 4 Ohms you will need a power supply of minimum +/-110 V. So the transistors in the amp will have to have a voltage rating of more than 220 V.
You will also need some protection circuits to protect the amp (and yourself!) if something goes wrong. 220 V can kill you!
If I was in your position I would eather buy an existing amp or go for a class D kit.
/Marcus
For 1500 Wrms @ 4 Ohms you will need a power supply of minimum +/-110 V. So the transistors in the amp will have to have a voltage rating of more than 220 V.
You will also need some protection circuits to protect the amp (and yourself!) if something goes wrong. 220 V can kill you!
If I was in your position I would eather buy an existing amp or go for a class D kit.
/Marcus
Dj BASS AMP said:
Let's assume your car amp really does output 1800W in a given impedance. (I doubt that, to be honest.) Let's further assume its efficiency is around 75%. Then it will draw (or better: try to draw) 2400W from your car's battery. That's 200A @ 12V. Not a resonable value.
If you want to use your car amplifiers for DJing at home or at parties, ditch its switch-mode power supply and build a new one (for 220V). That'll be better than transforming down from 220 V AC to 12V DC and back again to some +/-110V if that was even possible.
If you could give me more info about your setup, what you already have and what you want to do with it, I can probably provide you some schematics.
djk,
Thank you very much for the information. Do you mean to say that a total of 16 output devices (MJ21193/94) would do for a 1200watt bridged amp ie., 4 devices per bank of one amplifier? That seems rather easy.
Another question is - would the thermal sensing be sufficient as shown in the Leach schematic ie., with diodes or do we need to use TO39 transistors in diode mode for better sensing?
You have suggested 55-0-55 volt 2kVa transformer. That would result in a voltage of about 75-77 volts. Isn't this too high a voltage for the standard Leach design, notwithstanding changing output devices from MJ15003/15004 to MJ21193/21194 and drivers from MJE15030/15031 to 2SC3281 or 2SC5200 and 2SA1302 or 2SA1943 respectively?
In the triple emmiter follower stage can the second transistors be changed from 2N3440/2N5416 to 2SB649 and 2SD669 as they are higher voltage/current devices. Also the higher voltage types viz., 2N3439 and 2N5415 are currently not available. Hence, would the lower voltage 2N3440/2N5416 be sailing a bit too close to the wind with your suggested power supply?
Thanks in advance for your help.
Thank you very much for the information. Do you mean to say that a total of 16 output devices (MJ21193/94) would do for a 1200watt bridged amp ie., 4 devices per bank of one amplifier? That seems rather easy.
Another question is - would the thermal sensing be sufficient as shown in the Leach schematic ie., with diodes or do we need to use TO39 transistors in diode mode for better sensing?
You have suggested 55-0-55 volt 2kVa transformer. That would result in a voltage of about 75-77 volts. Isn't this too high a voltage for the standard Leach design, notwithstanding changing output devices from MJ15003/15004 to MJ21193/21194 and drivers from MJE15030/15031 to 2SC3281 or 2SC5200 and 2SA1302 or 2SA1943 respectively?
In the triple emmiter follower stage can the second transistors be changed from 2N3440/2N5416 to 2SB649 and 2SD669 as they are higher voltage/current devices. Also the higher voltage types viz., 2N3439 and 2N5415 are currently not available. Hence, would the lower voltage 2N3440/2N5416 be sailing a bit too close to the wind with your suggested power supply?
Thanks in advance for your help.
OK,
an example:
http://www.soundstream.com/TARANamp1.html
This tarantula delivers 2000W RMS into 4 and 2 Ohm. WITH ANALOG OUTPUT!
The TR1760/D is a digital amplifier, delivering 1760W RMS mono. No problems.
My own amps are not THAT big, but it's one Phase Linear PB Six (6x110W RMS) and one Phase Linear Opus 1 (1x 1080W RMS), using 35mm2 cable, 200A Wafer and a Brax 1 Farad capacitor.
About the need of 1500W RMS... you're right about the fact that a lot of amplifiers have a way to small power supply. The specs say it delivers 2x1500W RMS, but actually it has a power supply of 1kVA. That's sad. But OK, that's the way almost 80% of the commercial multichannel amplifiers work! Thay say 6x100W... that means 6x100W music power, let's say that is 6x70W RMS.
BUT: it can only give 70W RMS from TWO channels at a time, since the power supply can only give 200W.
My conclusion: why do we need to discuss whether he needs 1500W of 500W RMS? (it's only 5 dB
)... Just discuss the designs.
Grtz, Joris
an example:
http://www.soundstream.com/TARANamp1.html
This tarantula delivers 2000W RMS into 4 and 2 Ohm. WITH ANALOG OUTPUT!
The TR1760/D is a digital amplifier, delivering 1760W RMS mono. No problems.
My own amps are not THAT big, but it's one Phase Linear PB Six (6x110W RMS) and one Phase Linear Opus 1 (1x 1080W RMS), using 35mm2 cable, 200A Wafer and a Brax 1 Farad capacitor.
About the need of 1500W RMS... you're right about the fact that a lot of amplifiers have a way to small power supply. The specs say it delivers 2x1500W RMS, but actually it has a power supply of 1kVA. That's sad. But OK, that's the way almost 80% of the commercial multichannel amplifiers work! Thay say 6x100W... that means 6x100W music power, let's say that is 6x70W RMS.
BUT: it can only give 70W RMS from TWO channels at a time, since the power supply can only give 200W.
My conclusion: why do we need to discuss whether he needs 1500W of 500W RMS? (it's only 5 dB
)... Just discuss the designs.Grtz, Joris
960 W RMS bursts / 1 channel
Hi!
You can try using this kind of module:
http://www.thel-audioworld.de/module/acuso/acuso.htm
Look at
for output power / power supply details...
Only drawback:
It has no protections whatsoever, so a short in the speakers will result in the death of the fets... a protection circuit would be needed
And it does not cost that much, and is absolute high end in sound...
Ciao,
Arndt
Hi!
You can try using this kind of module:
http://www.thel-audioworld.de/module/acuso/acuso.htm
Look at
An externally hosted image should be here but it was not working when we last tested it.
for output power / power supply details...
Only drawback:
It has no protections whatsoever, so a short in the speakers will result in the death of the fets... a protection circuit would be needed
And it does not cost that much, and is absolute high end in sound...
Ciao,
Arndt
You could also take a look at "The End Millennium" from LCAudio.
It can give 800W RMS into 1 Ohm. But I don't think it's perfect for PA since it has (just like the ThelAudio AccuSound 100) been designed for high-end audio.
It don't know if it's suitable for PA: No protection and you don't know how the amp handles when it drives continuously at full power!
But, just take a look.
Grtz, Joris
It can give 800W RMS into 1 Ohm. But I don't think it's perfect for PA since it has (just like the ThelAudio AccuSound 100) been designed for high-end audio.
It don't know if it's suitable for PA: No protection and you don't know how the amp handles when it drives continuously at full power!
But, just take a look.
Grtz, Joris
Re: 960 W RMS bursts / 1 channel
Note also: It says "kurzeitig", =intermittent, short pulses! This amp has fundamentally wrong design of the transistor mounting in order to deliver high power. You must have much more material below the transistors. You can't transport heat with more transistors and not more heat conducting material.
Check my experiment!
http://home5.swipnet.se/~w-50719/hifi/qro/prototype_qro.html
Cradle22 said:
Note also: It says "kurzeitig", =intermittent, short pulses! This amp has fundamentally wrong design of the transistor mounting in order to deliver high power. You must have much more material below the transistors. You can't transport heat with more transistors and not more heat conducting material.
Check my experiment!
http://home5.swipnet.se/~w-50719/hifi/qro/prototype_qro.html
I've had some carbon paper, too
I wouldn't use a high end amplifier for DJing. Most of them are not rugged enough. The heat problem being the most important. They are not made for running constantly at max power.
No Thel, no LCAudio, no PWM / digital amplifier...
If you have an active crossover, you can still use high end amplifiers for mids and tweeters and get a better sound.
Again, tell me more about your setup and I will provide you a very simple, cheap and rugged PA amplifier design, including a protection circuit.
Agreed. You won't hear much difference. But a 500W amplifier is way cheaper and easier to implement and less a risk for a newcomer than a 1500W circuit.
I wouldn't use a high end amplifier for DJing. Most of them are not rugged enough. The heat problem being the most important. They are not made for running constantly at max power.
No Thel, no LCAudio, no PWM / digital amplifier...
If you have an active crossover, you can still use high end amplifiers for mids and tweeters and get a better sound.
Again, tell me more about your setup and I will provide you a very simple, cheap and rugged PA amplifier design, including a protection circuit.
Agreed. You won't hear much difference. But a 500W amplifier is way cheaper and easier to implement and less a risk for a newcomer than a 1500W circuit.
"It can give 800W RMS into 1 Ohm. But I don't think it's perfect for PA since it has (just like the ThelAudio AccuSound 100) been designed for high-end audio.
It don't know if it's suitable for PA: No protection and you don't know how the amp handles when it drives continuously at full power!"
Vigier,
as far as I know the Millenium is protected, my Zapsolutes are heat and short protected. What kind of protection are you missing in the Millenium?
Besides, the Millenium is being used in studios and should do just fine in a DJ set up (even though I would choose a PWM for obvious reasons).
AMT-freak
"I wouldn't use a high end amplifier for DJing. Most of them are not rugged enough. The heat problem being the most important. They are not made for running constantly at max power.
No Thel, no LCAudio, no PWM / digital amplifier..."
??? Heat is one of the big reason for choosing a PWM amp since it is more efficient than any other design.
And the Zapulse IS made to run at max power constantly, and according to LC Audio it does it without sweating.
Actually...
/Peter
It don't know if it's suitable for PA: No protection and you don't know how the amp handles when it drives continuously at full power!"
Vigier,
as far as I know the Millenium is protected, my Zapsolutes are heat and short protected. What kind of protection are you missing in the Millenium?
Besides, the Millenium is being used in studios and should do just fine in a DJ set up (even though I would choose a PWM for obvious reasons).
AMT-freak
"I wouldn't use a high end amplifier for DJing. Most of them are not rugged enough. The heat problem being the most important. They are not made for running constantly at max power.
No Thel, no LCAudio, no PWM / digital amplifier..."
??? Heat is one of the big reason for choosing a PWM amp since it is more efficient than any other design.
And the Zapulse IS made to run at max power constantly, and according to LC Audio it does it without sweating.
Actually...
/Peter
One thing again about the Thel amp: You know that the aluminium bar on which the transistors rest is used to mount them against a large (and I mean very large) heatsink?
And as for LCAudio "The End Millenium", well, I have two of those modules in use, and the protection circuitry is excellent. But I would not try to get more than 400 W out of them, even with a parallel transistor board.
But I have to say that I am very impressed by the performance of those Sanken fets they use, I could recommend them for DJ equipment as well - nice mounting surface, very good heat dissipation...
But they don't come cheap...
Maybe the 300W Sub amp from ESP could help, since it can be paralleled, as well...
And as for LCAudio "The End Millenium", well, I have two of those modules in use, and the protection circuitry is excellent. But I would not try to get more than 400 W out of them, even with a parallel transistor board.
But I have to say that I am very impressed by the performance of those Sanken fets they use, I could recommend them for DJ equipment as well - nice mounting surface, very good heat dissipation...
But they don't come cheap...
Maybe the 300W Sub amp from ESP could help, since it can be paralleled, as well...
If I remember correctly, the LCAudio Millenium's power cannot be increased that easy. It's a design without feedback and LCAudio say that just paralleling output devices would seriously affect sound quality (high order harmonics because of subtle differences between the devices). You can add those additional output boards, but if you look closer, they just give you another speaker output. They are using the Millenium board as a driver for multiple output stages. Easy if there is no feedback. The Sanken devices are fine, but they are BJTs, no FETs. Using just one single pair of output devices, I would never go higher than 100W per channel in a PA environment.
The PWM units are quite efficient, but they have different problems. They are not very reliable when used for PA.
For PA, you need protection against DC, overload, over-temperature and a circuit driving a speaker relay which prevents turn-on and turn-off thump.
Most high end units merely have a power-on-delay. A DC servo is no protection against DC at the output when output devices get shorted.
Just from experience and from fixing many many PA amplifiers, and remembering their mechanical and electrical ruggedness and protection circuits, I wouldn't recommend LCAudio or Thel or any similar high end kits. They are clearly intended for home use.
Your amplifiers will have to take a lot of abuse...
If you build a simple circuit with reasonable power per channel (maybe 200W .. 600W RMS) and add a good protection circuit, that'll be cheaper and more accurate.
I was thinking of something like PA-600 or a circuit from www.aussieamplifiers.com
The PWM units are quite efficient, but they have different problems. They are not very reliable when used for PA.
For PA, you need protection against DC, overload, over-temperature and a circuit driving a speaker relay which prevents turn-on and turn-off thump.
Most high end units merely have a power-on-delay. A DC servo is no protection against DC at the output when output devices get shorted.
Just from experience and from fixing many many PA amplifiers, and remembering their mechanical and electrical ruggedness and protection circuits, I wouldn't recommend LCAudio or Thel or any similar high end kits. They are clearly intended for home use.
Your amplifiers will have to take a lot of abuse...
If you build a simple circuit with reasonable power per channel (maybe 200W .. 600W RMS) and add a good protection circuit, that'll be cheaper and more accurate.
I was thinking of something like PA-600 or a circuit from www.aussieamplifiers.com
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