Christophe,
I do understand what you are saying exactly. The simpler you can achieve the end result the better the micro details will be preserved. Like you I understand that there is a point where chasing lower distortion numbers it seems would actually add some other type of distortion mechanism that we just don't know how to measure, what exactly we are looking for. Ears should be the final arbitrator I would think.
I do understand what you are saying exactly. The simpler you can achieve the end result the better the micro details will be preserved. Like you I understand that there is a point where chasing lower distortion numbers it seems would actually add some other type of distortion mechanism that we just don't know how to measure, what exactly we are looking for. Ears should be the final arbitrator I would think.
Nearly impossible to do with this design - the 2 blocking caps at the input pair
can't be shorted (at HF) ,like I did with the 1K test. you'll have to build one and
do it for REAL !! 😛
OS
OS,
Are you saying you can't do a two tone test in simulation or are you talking about something in the design that would block a 19khz+20khz signal? I hope you are just saying you can't simulate this.
Are you saying you can't do a two tone test in simulation or are you talking about something in the design that would block a 19khz+20khz signal? I hope you are just saying you can't simulate this.
C10/11 (470u) on the KC. On most simulations the blocking caps are not necessary
to simulate correctly (a little more offset).
This will not run without the blockers (sim or real). 😱
This is what drops the noise floor on a FFT simulation (no big caps).
OS
to simulate correctly (a little more offset).
This will not run without the blockers (sim or real). 😱
This is what drops the noise floor on a FFT simulation (no big caps).
OS
Of course I can "see" it 😀. As far as in simulation realm, it is not audible. What I meant with "ugly face" was not that, but some kind of "trade-off" of this good performance soundwise. I think something is "not right" there (or I accidentally made mistake with the circuit, or it is NOT your final version). Not with the topology as my modified LATFET version is just perfect (I'm happy I cannot find "problem" with such VAS, they should have built/modified the crescendo amplifier with this VAS).
In real implementation, I would try to capture or listen for "unnatural tone/timbre" from this amp.
Ostripper
For this situation ( simulation ) you can change the capacitor values to very high values like 100 farads or more and the harmonics wiil be exposed.
For this situation ( simulation ) you can change the capacitor values to very high values like 100 farads or more and the harmonics wiil be exposed.
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Is that really a Logitec Subwoofer? I thought they just made crappy little computer speakers!
No , especially the old 90's logitech , used the Tang-band http://www.tb-speaker.com/detail/1208_03/wt-644f.htm 180W unit.
New ones are likely chinese cheapo's , this one is real taiwan power , huge magnet
and voice coil.
I already aligned this one to 26hz / w 14" 100mm port. Shakes the whole house.
Your Sankens will be a good match. In fact , I might limit that amp a little.
It can barely hit 1/2 X-max with the full 90W of my H/K receiver.
OS
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What input do you think would be the best choice to drive a subwoofer? I've got 4 Dayton SV-2 drivers waiting for a home.
Dayton SVS-12 drivers ??
For a 12" , exactly what I'm using - the Sankens. They could do a 2R sub (SOA - wow!!) 😱
For input -
The wolverine without TMC and a 100pF miller cap , lower input filter 390pf (C2) and a larger input cap 6.8uf along with a 330uF dc blocker.
No cap multipliers , either. (below)
You don't need slew , just better cooling and more current. No voltage drop to
the IP stage is better for my supply , as well.
OS
Attachments
I'll likely be running 2 drivers on one supply. Do you think it's work inverting one amp input so each channel is running on opposite rails?
What woofer (exact model#)
- Even if you ran 2- 8R subs in parallel you would
not get close to the 3 pair sanken SOA @ 60 v rails. You would be at 400W
and your neighbors would hate you. 😀
You normally need to invert and bridge amps when you run a 8R woofer off
of 40V rails - my tang-band logitech was 2 PAIR paralleled AND bridged
LM3886 (4 amp chips) for 120+ W. 2 more Ic's for the stereo satellites -
6 amps in the box and a big 30-0-30 trafo .
OS
They are older ACI SV-12.1 drivers (I don't know why I keep calling them Daytons). The same one used in the Titan Subwoofer. 4 Ohm coils. Loading an amp at 2 ohms just seems too car audio to me. I'm planning to build a separate amp for each driver.
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Run the coils in series (8R), power it with a 3X sanken or 5X ON slewmaster
on 75V rails - perfect.
Box= 4 cu. ft. with a 17" long X 4" dia sewage pipe. 21hz will rock your world.
Just 1 driver will do ....unless your living room is a cathedral. 😀
Don't waste that woofer on a sealed car audio enclosure.
You could do the separate amp thing (2 X 4R)- same amp recommendation X 2 , but @ 50-60V rails.
My upgrade choice is the 10" 4R dayton RSS265HF-4 10"
- it matches my box / alignment perfect.
My amp would give it 250+ w @ 4R - at least.
OS
We've tried these drivers in a box that size. They would hit the end stops very loudly. I think that's why they recommended a sealed enclosure normally. I've always wondered if the amps he was using were doing nasty things when they clipped.
jwilhelm,
It sounds like the speaker you are talking about would be considered an air suspension speaker designed for a closed box. That may be the case but it does not mean you can't design a vented box to work with them. If you have the Thiel/Small values there are many calculators out there that can give you the proper box size and vent tube size to do what you want to do. It sounds like you would probably need a fairly small box with a long port length. I imagine the designer of that speaker was thinking how small a box can we use to make home users happy, most people don't want large sub=woofer cabinets in there rooms, that is a problem for many traditional bass speaker designs, they are not meant for small boxes. If the speaker is slamming up against the stops as you say you could easily damage the voicecoil when it runs up against the back plate and smashes the voicecoil former. If you seal the larger box you are talking about and it is still showing this behavior the box is obviously way to large to load the diaphragm. Check one of the calculators and I would assume your box size is way off.
It sounds like the speaker you are talking about would be considered an air suspension speaker designed for a closed box. That may be the case but it does not mean you can't design a vented box to work with them. If you have the Thiel/Small values there are many calculators out there that can give you the proper box size and vent tube size to do what you want to do. It sounds like you would probably need a fairly small box with a long port length. I imagine the designer of that speaker was thinking how small a box can we use to make home users happy, most people don't want large sub=woofer cabinets in there rooms, that is a problem for many traditional bass speaker designs, they are not meant for small boxes. If the speaker is slamming up against the stops as you say you could easily damage the voicecoil when it runs up against the back plate and smashes the voicecoil former. If you seal the larger box you are talking about and it is still showing this behavior the box is obviously way to large to load the diaphragm. Check one of the calculators and I would assume your box size is way off.