Hello all,
I need an amplifier to power a pair of DIY ribbons... final load should be around 1 ohm... but I'm going to say 0.7 to be safe
Any amp type will do, though class A is preferred (I know that this design is tough)... don't worry if Class A is too complicated
Linesource on here had posted several schematics to make this amp...
but again... design doesn't matter
Optimially I would like it to have as low of distortion as possible...
Requirements:
>0.01% THD
Stable daily at 0.7 ohms
2 channel amplifier
gain control knob
input and output RCAs/XLR/.25" microphone (any of these... not all)
35-55 watts per channel (ideally on the high end)
mosfets are fine, as all are topographies... no need to build the amp case... you can just supply the put together PCB board...
Here's linesources schematic:
http://www.diyaudio.com/forums/attachment.php?s=&postid=448463&stamp=1091084434
Quote me prices people and thank you in advance
I need an amplifier to power a pair of DIY ribbons... final load should be around 1 ohm... but I'm going to say 0.7 to be safe
Any amp type will do, though class A is preferred (I know that this design is tough)... don't worry if Class A is too complicated
Linesource on here had posted several schematics to make this amp...
but again... design doesn't matter
Optimially I would like it to have as low of distortion as possible...
Requirements:
>0.01% THD
Stable daily at 0.7 ohms
2 channel amplifier
gain control knob
input and output RCAs/XLR/.25" microphone (any of these... not all)
35-55 watts per channel (ideally on the high end)
mosfets are fine, as all are topographies... no need to build the amp case... you can just supply the put together PCB board...
Here's linesources schematic:
http://www.diyaudio.com/forums/attachment.php?s=&postid=448463&stamp=1091084434
Quote me prices people and thank you in advance
You can use this good old amp:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=31077
Just have the person making it for you to add lots of output devices
http://www.diyaudio.com/forums/showthread.php?s=&threadid=31077
Just have the person making it for you to add lots of output devices
ACD said:You can use this good old amp...Just have the person making it for you to add lots of output devices
I currently have three devices per rail. I'll see how low I can drive it later this week!
What sort of power do you need? I imagine 5-10w should be more than enough if your sensitivity is that good. That means the rail voltage can be dropped significantly from the 35-40V used in the current prototypes.
Board orders will be taken soon.
pinkmouse said:
I currently have three devices per rail. I'll see how low I can drive it later this week!
What sort of power do you need? I imagine 5-10w should be more than enough if your sensitivity is that good. That means the rail voltage can be dropped significantly from the 35-40V used in the current prototypes.
Board orders will be taken soon.
10 watts would work... but I would like 25-35 for overhead...
are you willing to make me one?
I understand all those schematics I don't know if I have the skills to make it.... I can try I guess
ACD said:You can use this good old amp:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=31077
Just have the person making it for you to add lots of output devices
If that is .7 ohm stable.... sure they can use that.... any design that's out there they can copy... as long as it meets my specs...
any takers??
I will pay well....
Re: How soon do you need it?
need it about 2 months... YGM
mwmkravchenko said:Send me a private email about the particulars and I will get back to you. You may have a taker.
Mark
need it about 2 months... YGM
Hi Audiophilenoob,
You may want to build your ribbons first and have your ears decide if this is true love, or just infatuation with a 150 lb Heavy Metal sculpture.
There are many amps that are stable into 2 ohms. You can buy or make a non-inductive 1 ohm resistor to put in series with your 1 ohm tweeter ribbon to trade-off 50% of the amp's power for transformer-free direct drive. A 100db/watt speaker only needs a few watts, but the first watt must have very low noise and distortion.
Many amplifier topologies can be adapted to drive a 1 ohm ribbon by dropping the output power supply to about 8 volts. There are high current 12V CT and 12.6V CT filiment transformers availble. The low driver stage voltages allow simple topologies with very low noise transistors to be used. The low output voltages make it simple to keep Class-A bipolar output transistors in the safe operating area.
You may want to build your ribbons first and have your ears decide if this is true love, or just infatuation with a 150 lb Heavy Metal sculpture.
There are many amps that are stable into 2 ohms. You can buy or make a non-inductive 1 ohm resistor to put in series with your 1 ohm tweeter ribbon to trade-off 50% of the amp's power for transformer-free direct drive. A 100db/watt speaker only needs a few watts, but the first watt must have very low noise and distortion.
Many amplifier topologies can be adapted to drive a 1 ohm ribbon by dropping the output power supply to about 8 volts. There are high current 12V CT and 12.6V CT filiment transformers availble. The low driver stage voltages allow simple topologies with very low noise transistors to be used. The low output voltages make it simple to keep Class-A bipolar output transistors in the safe operating area.
Re: Now we need a carrot
LOL well I can send you what you think it will cost... I can buy parts you need and send them to you and send you money when you're done... either way... let me know in an email or on here...
mwmkravchenko said:
OK now what?
MArk
LOL well I can send you what you think it will cost... I can buy parts you need and send them to you and send you money when you're done... either way... let me know in an email or on here...
LineSource said:Hi Audiophilenoob,
You may want to build your ribbons first and have your ears decide if this is true love, or just infatuation with a 150 lb Heavy Metal sculpture.
There are many amps that are stable into 2 ohms. You can buy or make a non-inductive 1 ohm resistor to put in series with your 1 ohm tweeter ribbon to trade-off 50% of the amp's power for transformer-free direct drive. A 100db/watt speaker only needs a few watts, but the first watt must have very low noise and distortion.
Many amplifier topologies can be adapted to drive a 1 ohm ribbon by dropping the output power supply to about 8 volts. There are high current 12V CT and 12.6V CT filiment transformers availble. The low driver stage voltages allow simple topologies with very low noise transistors to be used. The low output voltages make it simple to keep Class-A bipolar output transistors in the safe operating area.
true I should wait and make sure this is ideal for me...
I don't want to add a resistor.. it is not the ideal solution and since I will have to purchase SOME amp for these I figured it might as well be the best one possible
It's hard to argue when your right!
This is the simplest method and most likely the cheapest. A properly paralleled number of LM3886 could even do this!
Mark
Allways willing to add flies to the ointment
There are many amps that are stable into 2 ohms. You can buy or make a non-inductive 1 ohm resistor to put in series with your 1 ohm tweeter ribbon to trade-off 50% of the amp's power for transformer-free direct drive. A 100db/watt speaker only needs a few watts, but the first watt must have very low noise and distortion
This is the simplest method and most likely the cheapest. A properly paralleled number of LM3886 could even do this!
Mark
Allways willing to add flies to the ointment
jacco vermeulen said:Shame you are so keen on low THD numbers, there are plenty of nice tube amplifiers that make ribbons do nightingale stuff
well I'm not particularly keen on it... I just didn't think Tubes could be .7 ohm stable...
can they????? links or anything?
LineSource said:Hi Audiophilenoob,
You may want to build your ribbons first and have your ears decide if this is true love, or just infatuation with a 150 lb Heavy Metal sculpture.
There are many amps that are stable into 2 ohms. You can buy or make a non-inductive 1 ohm resistor to put in series with your 1 ohm tweeter ribbon to trade-off 50% of the amp's power for transformer-free direct drive. A 100db/watt speaker only needs a few watts, but the first watt must have very low noise and distortion.
Many amplifier topologies can be adapted to drive a 1 ohm ribbon by dropping the output power supply to about 8 volts. There are high current 12V CT and 12.6V CT filiment transformers availble. The low driver stage voltages allow simple topologies with very low noise transistors to be used. The low output voltages make it simple to keep Class-A bipolar output transistors in the safe operating area.
ideally for a resistor a non-inductive 1 ohm with 1% tolerances?
any certain types that I should pick up for testing?
Hi,
I'm not a valve head so I'm talking out the top of my hat.
Most valve amps are transformer coupled to the load and they use a fixed turns ratio to determine the nominal load value.
It seems to me that you specify the turns ratio to suit 0r5, 0r7, 1r0 instead of the usual 4r & 8r.
When setting it up the designer will ensure it is stable.
I'm not a valve head so I'm talking out the top of my hat.
Most valve amps are transformer coupled to the load and they use a fixed turns ratio to determine the nominal load value.
It seems to me that you specify the turns ratio to suit 0r5, 0r7, 1r0 instead of the usual 4r & 8r.
When setting it up the designer will ensure it is stable.
Can tubes be stable into .7 ohms?
Well if the output transformer is wound for a 1ohm output probably they can - but I thought you were trying to avoid a transformer...
Seems in the distant past I have seen a transformer coupled amp with 2 and maybe 1 ohm taps, but it might have been one of those McIntosh transistor amps with output transformers.
Bill
Edit: Andrew beat me to the cooment
Well if the output transformer is wound for a 1ohm output probably they can - but I thought you were trying to avoid a transformer...
Seems in the distant past I have seen a transformer coupled amp with 2 and maybe 1 ohm taps, but it might have been one of those McIntosh transistor amps with output transformers.
Bill
Edit: Andrew beat me to the cooment
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