Why build SOZ?
For the fun, for the glory, but mostly for the fun.... Maybe there never will be any glory..
-Low damping factor
-PSU noise cancelation¨
-Simple with few parts
-To try something different!
Speakers: MJ King OBs with 4" Fostex
SOZ wil be used with the Fostex.
Have active xover.
No need for high power.
Have tried the ACA. Its really good!!
Now I have a diy F2 with resistor instead of CCS.
My F2 is in not as smooth as tha ACA, but sounds lively on the Fostexes!
The main reason for posting in this thread is to find out if the SOZ is possible to build into my existing enclosure without burnig up, or sound to bad.
My enclosure is about the size of the 5U.
For the fun, for the glory, but mostly for the fun.... Maybe there never will be any glory..
-Low damping factor
-PSU noise cancelation¨
-Simple with few parts
-To try something different!
Speakers: MJ King OBs with 4" Fostex
SOZ wil be used with the Fostex.
Have active xover.
No need for high power.
Have tried the ACA. Its really good!!
Now I have a diy F2 with resistor instead of CCS.
My F2 is in not as smooth as tha ACA, but sounds lively on the Fostexes!
The main reason for posting in this thread is to find out if the SOZ is possible to build into my existing enclosure without burnig up, or sound to bad.
My enclosure is about the size of the 5U.
There are some switching wall power adapters, in the same format as the ACA with higher currents and voltages. I've seen some in the 30volt range and I've even seen a 48volt at 3 amp supply on ebay used for power-over-ethernet:
AC 100V 240V Converter Adapter DC 48V 3A 144W Power Supply Charger DC 5 5x2 5mm | eBay
You may be able to do something with that, it's only $20, perhaps that would work if you ran it at a lower current (higher distortion, lower power).
There is also a 12v@10A for $15, I wonder if you can run two in series, 24v at 10A would be perfect for a F1. In series it's safe if you disconnect one of them because no current can flow in this topology. But before trying to run them in series you must confirm the ps is not connected to ground:
DC 12V 10A Converter Adapter 120W Power Supply for 5050 3528 LED Strip Module | eBay
AC 100V 240V Converter Adapter DC 48V 3A 144W Power Supply Charger DC 5 5x2 5mm | eBay
You may be able to do something with that, it's only $20, perhaps that would work if you ran it at a lower current (higher distortion, lower power).
There is also a 12v@10A for $15, I wonder if you can run two in series, 24v at 10A would be perfect for a F1. In series it's safe if you disconnect one of them because no current can flow in this topology. But before trying to run them in series you must confirm the ps is not connected to ground:
DC 12V 10A Converter Adapter 120W Power Supply for 5050 3528 LED Strip Module | eBay
Sorry 2 pico! I mentioned wrong enclosure! My bad!
My enclosure is smaller, about same size as standard FW.
How much can the standard FW dissipate?
@LBHajdu:
Thanks for reply, but will go linear on the PSU!
SOZ needs plus, minus and ground. Don`t know if SMPS is a good idea then...
With 12-13VDC rail on the SOZ thinking toroid needs to be at least 300VA?
My enclosure is smaller, about same size as standard FW.
How much can the standard FW dissipate?
@LBHajdu:
Thanks for reply, but will go linear on the PSU!
SOZ needs plus, minus and ground. Don`t know if SMPS is a good idea then...
With 12-13VDC rail on the SOZ thinking toroid needs to be at least 300VA?
Though it's technically possible to make a plus, minus with two isolated SMPS, in most amps if you unplug one but not the other the speaker cone would most likely leap out of the basket because the whole bias current is being dumped in the voice coil. The SOZ is actually an exception, however you're right in stating that it's not the most elegant solution.
Keep it under 100W per channel. Possibly 90W as a rough guide.Sorry 2 pico! I mentioned wrong enclosure! My bad!
My enclosure is smaller, about same size as standard FW.
How much can the standard FW dissipate?
Start with that, measure temp if it's warm keep going till it feels just on the hot side.
Thanks for replies!
My F2 is a "sissy" version with only 20VDC and 2A Ids -> total 80w dissipation.
Can keep hands on for 1min.
Don`t have to much space for it in bench, so gets a little warm.
Zen: Trying to find "then a little back" without amp and house meltdown..
Looking at F1 article, the F1 dissipates 100w each channel, total 200w.
Think your answer is about spot on 2pico.
If using Arcol resistors for the 8ohms in SOZ, is there a rule of thumb for power rating?
Is 100w power rating enough with mentioned enclosure and about 100w dissipation?
Think the Arcols can handle max temp of 200`C.
My F2 is a "sissy" version with only 20VDC and 2A Ids -> total 80w dissipation.
Can keep hands on for 1min.
Don`t have to much space for it in bench, so gets a little warm.
Zen: Trying to find "then a little back" without amp and house meltdown..
Looking at F1 article, the F1 dissipates 100w each channel, total 200w.
Think your answer is about spot on 2pico.
If using Arcol resistors for the 8ohms in SOZ, is there a rule of thumb for power rating?
Is 100w power rating enough with mentioned enclosure and about 100w dissipation?
Think the Arcols can handle max temp of 200`C.
Sweet!
When looking for toroid only finding 2x9v 300VA, 2x12v 300VA and 2x12v 400VA.
2x12v will give almost ~16VDC.
Trying to calculate dissipation with 10ohms instead of 8ohms with my simple math knowledge....
I already have 10ohm resistors. Will try calculate with 16VDC rail.
In article IRFP have about 20w dissipation, same as 8ohm resistor have about 20w dissipation.
Can then say 8ohm for IRFP.
If using 10ohm resistor IRFP will have a litle more than 8ohm.
Calculate R = 10ohm + 8ohm + 1ohm + 10ohm = 29ohm
Ids = U/R = 32v/29ohm = 1.1034A
Total Ids = 1.1034 x 4 = 4.414A
Total dissipation for the amp both sides:
P = U x I = 32v x 4.414A = 141W
Will probably be a littlebit less dissipation since IRFP will have a little more resistance.
Than add dissipation from rectifiers and toroid.
Is this correct or do I have to go elementary school once again......
When looking for toroid only finding 2x9v 300VA, 2x12v 300VA and 2x12v 400VA.
2x12v will give almost ~16VDC.
Trying to calculate dissipation with 10ohms instead of 8ohms with my simple math knowledge....
I already have 10ohm resistors. Will try calculate with 16VDC rail.
In article IRFP have about 20w dissipation, same as 8ohm resistor have about 20w dissipation.
Can then say 8ohm for IRFP.
If using 10ohm resistor IRFP will have a litle more than 8ohm.
Calculate R = 10ohm + 8ohm + 1ohm + 10ohm = 29ohm
Ids = U/R = 32v/29ohm = 1.1034A
Total Ids = 1.1034 x 4 = 4.414A
Total dissipation for the amp both sides:
P = U x I = 32v x 4.414A = 141W
Will probably be a littlebit less dissipation since IRFP will have a little more resistance.
Than add dissipation from rectifiers and toroid.
Is this correct or do I have to go elementary school once again......
Trying to calculate Rds for IRFP240.
Maybe sombody can help me finding the Vgs, Id, and Vds combination for me on the SOZ?
Finding out it has something to do with Id-Vds curve but can`t quite draw it into the IRFP240 curve.
https://www.chegg.com/homework-help/definitions/mosfet-bias-and-load-lines-4
Maybe sombody can help me finding the Vgs, Id, and Vds combination for me on the SOZ?
Finding out it has something to do with Id-Vds curve but can`t quite draw it into the IRFP240 curve.
https://www.chegg.com/homework-help/definitions/mosfet-bias-and-load-lines-4
Found attached curve for IRFP240 after searching for a while.....
As its mentioned:
"For those wondering about IRF mosfets, here are some load lines I have re-drawn from the IRF data
sheets which are actually hopelessly inadequate for most people who wish to use the mosfets with low
drain supply voltages and high idle currents for class A."
solidstateamps5+tube-input
As its mentioned:
"For those wondering about IRF mosfets, here are some load lines I have re-drawn from the IRF data
sheets which are actually hopelessly inadequate for most people who wish to use the mosfets with low
drain supply voltages and high idle currents for class A."
solidstateamps5+tube-input
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