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"HIFI Electronical 2 Way Crossover PCBA ClassA Power Linkwitz-Riley filter 4-Channel Output Crossover-point 2.2K Hz Free Shipping"
I've bought two of these with X-O points at 80 and 100hz for use with sub-woofers for my single driver MTLT systems.
Having frequencies down to a measured 30hz adds a subtle but valuable fullness to some music.
I used MathAudio's free plug in for FooBar to flatten out the peaks in my systems.
Anyway... Has anybody done testing on these $30 active X-Os?
Does the design look OK? 'Seems so inexpensive... less than passive X-Oers.
Thanks, Mack
The NE5532 op amps are fine, and the Linkwitz-Riley circuit is good. This board is likely better than
any passive crossover that you could build instead for your woofers. Active crossovers in general
are better than passive.
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thanks rayma, I thought the active XOs were an improvement but I know better than to trust my ears.... well, I trust my ears, but my brain is so dam suggestible.
I swear the bass tightened up after replacing the NE5532s with TI Burr-Brown OPA2604s. Of course I expected it to so......
I swear the bass tightened up after replacing the NE5532s with TI Burr-Brown OPA2604s. Of course I expected it to so......
The above circuit buffer opamps 1b & 5b are a gain of 2, with a level trimpot in front, this isolates the also the xover opamp 1c 5c from the outside world.
It would have been nice if the Chinese xover had this and a level trimpot as well.
Cheers George
It would have been nice if the Chinese xover had this and a level trimpot as well.
Cheers George
What the DIY audio store could perhaps use is a PCB /kit for simple, adjustable active 2-way line level XO for those folks not able to design their own, nor quite ready to take the leap to minidsp or such - something that could be piggy-backed with something like the B1 or Mesmerize line stage/ buffer, perhaps even in the same enclosure?
There are probably more than a few of us with sufficient amps kicking around, but from my own readings, the sonics of the minidsp's onboard DACs could easily be improved. However, for those of us not enthralled at the prospect of building the multiples of required channels of DACs, that means the expense and complication of at least 2 more little boxes and associated interconnects
There are probably more than a few of us with sufficient amps kicking around, but from my own readings, the sonics of the minidsp's onboard DACs could easily be improved. However, for those of us not enthralled at the prospect of building the multiples of required channels of DACs, that means the expense and complication of at least 2 more little boxes and associated interconnects
Trouble is with this Chinese xover if the amps are not the same gain then you have no adjustment of volume over the highs or lows on this xover, so to get the balance right.
So it would have been nice to have a level control with output buffer after the highpass and low pass sections, to fine tune the balance between highs and lows. (just like the one I posted)
Cheers George
So it would have been nice to have a level control with output buffer after the highpass and low pass sections, to fine tune the balance between highs and lows. (just like the one I posted)
Cheers George
Most audio poweramps don't have level controls, unless you search for ones with input level controls.
Cheers George
The majority of poweramps usually don't, at least the ones I've had in the last 40 years of hi end audio.
Sorry one did the 1976 Yamaha P2200 poweramp did, and it had a very good pot, an Alps Black Beauty, even better than the Blue Velvet, the amp was OK'ish good bass, mids and highs so so.
Why not just have a level trimpots on the xover like all active xover have, and then it will suit everyone.
Cheers George
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No money for hi end, that's why I hang around here.
For example almost all Parasound power amps has level or gain control. I prefer controls for safety reasons , an fully open power amp is to asking for trouble. Sooner or later somebody will disconnect or connect a cable and the bass diaphragm will fly across the room.
For example almost all Parasound power amps has level or gain control. I prefer controls for safety reasons , an fully open power amp is to asking for trouble. Sooner or later somebody will disconnect or connect a cable and the bass diaphragm will fly across the room.
I've just ordered my 3rd. This one will be set to 350Hz for a FAST system.
I expect delivery in 6 weeks. It's nice to drag out the process for more enjoyment, heh.
Ordered a " Chassis Transformer 6VA 18V+18V" from the bay of E.
I expect delivery in 6 weeks. It's nice to drag out the process for more enjoyment, heh.
Ordered a " Chassis Transformer 6VA 18V+18V" from the bay of E.
The most major problem I see with active crossovers (and maybe DSP) is now losing the clarity of the LDR preamp!!!!! (thanks again)
It would be great to have an active or passive crossover that doesn't compromise that. Something like the Boozhounds Jfet or simpler. JFET Crossover Kit – Boozhound Laboratories
What, if any, crossovers do you use for your Martin Logans, George. I want to go active on my Sequels (or DSP), but I am now worried about degrading the sound.
It would be great to have an active or passive crossover that doesn't compromise that. Something like the Boozhounds Jfet or simpler. JFET Crossover Kit – Boozhound Laboratories
What, if any, crossovers do you use for your Martin Logans, George. I want to go active on my Sequels (or DSP), but I am now worried about degrading the sound.
I use the passive 18db xover of the ML's to the ESL panels, but use (150hz) 24db active to the bass units. (Attached) (Also I use better opamps than the TLO74's)
I don't use the high pass of this circuit as it's not as transparent as the passive of the ML's.
Cheers George
I don't use the high pass of this circuit as it's not as transparent as the passive of the ML's.
Cheers George
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Here is the three way of the same active xover. Very well thought out, as you can see input and output buffers to keep all active xover components isolated from the outside world, with level pre-set trimpots before the output buffers.
http://archive.siliconchip.com.au/cms/A_30278/article.html
http://archive.siliconchip.com.au/cms/A_30278/article.html
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I replaced the JRC's NE5532 opamps that came with the Chinese XO with
"TI Burr-Brown OPA2604AP OPA2604 Low Noise OP AMP IC x5"
I imagined that the Burr-Browns tightened up the bass.... but I was expecting a change so naturally, heard one
Thanks, Mack