The X-BosoZ hasn't got a lot of gain. Actually it has problems driving several amps to full output, or clipping!
I just had a thought; would it be possible to daisy-chain 2 (two) NS10 modules to get enough gain to feed the F4? Apassgear's NS10 schematic attached. Might be the answer, until something else shows up.
Other ideas and suggestions are welcomed too
Steen
I just had a thought; would it be possible to daisy-chain 2 (two) NS10 modules to get enough gain to feed the F4? Apassgear's NS10 schematic attached. Might be the answer, until something else shows up.
Other ideas and suggestions are welcomed too
Steen
Attachments
I don't think you'll be able to get much more voltage swing - at least not with the 24V rail. What you could do is increasing the voltage, perhaps to something like 50V and increase the value of R8 to get more gain. You might also need to do some adjustments to the other values to make them work well with the higher rail.
It would be cool to convert it to +/- 25V rails and perhaps get rid of some of the coupling caps.
It would be cool to convert it to +/- 25V rails and perhaps get rid of some of the coupling caps.
have you headphone output on your CD player?lykkedk said:...............
Jesper
try to feed Babelfish from that output,just for test.....then tell us what you hear.
25~30W is plenty of oooompfhghs ,in A class , anyway.....
steen- one of first NS10Klone variants (with+/- supply) can be better,regarding swing
and-also.little fiddling with feedback resistors can bring little more .......
The concept of daisy-chaining is desribed here: http://sound.westhost.com/project37.htm Just above the picture of the prototype.
We tried to make a splitrail version sometime ago. Russ White's schematic is attached. I have one playing at home and will try to hook it up with the F4.
Steen
We tried to make a splitrail version sometime ago. Russ White's schematic is attached. I have one playing at home and will try to hook it up with the F4.
Steen
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steenoe said:
I think that the increasing gain is possible. It is also possible with BOSOZ. The distortion numbers are going up, though. BTW, which amp has low distortion with high gain . . .
When the music is reproduced correctly, I'm often tempted to increase volume because I feel as if the sound pressure level were low. In opposite way, the lousy music gives me feeling of high sound pressure.
fe108ez
Excuse the momentary diversion of ths F4 amplifier thread.
Of all the fostex drivers I have, I like the midrange clarity and less of that piercing sound of other fostex , and it does a decent full range. I built 2 single horns previous; this HM Saxaphon inspired design is my own; I call it HM Alto. It uses the fe108ez+mcm 8"which was the driver for the "Tuba " sub. Each enclosure has a front horn and a rear 8" sub horn.These drivers are hooked up out of phase with no X-over, presenting a 3 ohm load which works fine with the A30. A little complicated to build but I am happy with them. If interested, I have some photos and plan at webshots. Email me for any questions re the fe108ez.
Excuse the momentary diversion of ths F4 amplifier thread.
Of all the fostex drivers I have, I like the midrange clarity and less of that piercing sound of other fostex , and it does a decent full range. I built 2 single horns previous; this HM Saxaphon inspired design is my own; I call it HM Alto. It uses the fe108ez+mcm 8"which was the driver for the "Tuba " sub. Each enclosure has a front horn and a rear 8" sub horn.These drivers are hooked up out of phase with no X-over, presenting a 3 ohm load which works fine with the A30. A little complicated to build but I am happy with them. If interested, I have some photos and plan at webshots. Email me for any questions re the fe108ez.
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Fascinating web site--thanks audiotux!
doggy, thanks for the info on the Fostex driver. I'm pretty good at designing horns, and like what you've come up with. Nice job.
I need to design something for the midbass region.
Sorry about the interruption, now, back to our regularly scheduled program.
doggy, thanks for the info on the Fostex driver. I'm pretty good at designing horns, and like what you've come up with. Nice job.
I need to design something for the midbass region.
Sorry about the interruption, now, back to our regularly scheduled program.
steenoe said:
I've been a little surprised that the X-BoSoZ has been a poor fit for the F4. The variant I designed, which the Twisted Pear guys also used, runs about 24dB of gain (or 16x) and doesn't start to clip until 19Vrms single ended output or 38Vrms balanced output, The only thing I can think of is the issue of having the volume attenuation on the output side giving an impedance mismatch with the F4 input, but with a 48k input impedance for the F4 I wouldn't think it would present that much of a problem.
That being said, I implicitly trust Steen's ears! Oh darn, I guess I'll just have to build an F4 so I can sort this out.
Terry
Banned
Joined 2002
metalman said:
I've been a little surprised that the X-BoSoZ has been a poor fit for the F4. The variant I designed, which the Twisted Pear guys also used, runs about 24dB of gain (or 16x) and doesn't start to clip until 19Vrms single ended output or 38Vrms balanced output, The only thing I can think of is the issue of having the volume attenuation on the output side giving an impedance mismatch with the F4 input, but with a 48k input impedance for the F4 I wouldn't think it would present that much of a problem.
That being said, I implicitly trust Steen's ears! Oh darn, I guess I'll just have to build an F4 so I can sort this out.
Terry
I agree
pm me i have something for you then
Banned
Joined 2002
I fully support that statement. Make no mistake, I am the biggest BosoZ fan aroundVariac said:
The best thing that could happen was if the X-CCS-CC-BosoZ could drive the F4, so I am very keen on finding the reason why mine has problems, if there are any. On another note; after having heard the difference between mosfet and Jfet inputs in poweramps (Babelfish/F4's on one hand, Zen's and Aleph's on the other) I also think that the BosoZ is in need of a major re-work/modification. Some cascoded nice little Toshiba's, you know. Hope you clever guy's will come up with something like that Well, that was another issue. The real issue on hand is if the X-BosoZ is able to match with the F4? For reference I have attached Metalman's original schematic. The gainsetting resistors are the pairs R19/R15 and R20/R16 if I am not mistaken. Note that R15 and R16 are 50k.I would like to add that I think Q3 and Q4 needs a gatestopper resistor each, at 221r.
What is the formula for calculating the gain in this circuit?
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This is Mr. White's schematic, which is the one I used. You will see some minor differences like the trimpots are missing, other than that the two schematic's are pretty much alike. The gainsetting resistors here, are the R14/R19 and R15/R18 pairs. Note that R19 and R18 are at 39k which is the only difference of importance that I can find when comparing to Terry's schematic. How much difference in gain does that mean? The only other difference that I can think of is that My positive rail runs at 60V!
Reflecting on the whole thing, it came to mind that I didnt connect the Negative-OUT to ground when connecting the BosoZ to the F4. I just unplugged it from the A-X's, which runs balanced. Would that have any influence on the gain?
If the Twisted is able to give 24dB gain, then it should have an easy time driving the F4. Hope we can sort this out together
Steen
Edit. Errata on this schematic: R5 should read 10k and not 221r!
Reflecting on the whole thing, it came to mind that I didnt connect the Negative-OUT to ground when connecting the BosoZ to the F4. I just unplugged it from the A-X's, which runs balanced. Would that have any influence on the gain?
If the Twisted is able to give 24dB gain, then it should have an easy time driving the F4. Hope we can sort this out together
Steen
Edit. Errata on this schematic: R5 should read 10k and not 221r!
Attachments
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