Sorry for insulting AndrewT, the last time i tryed adjusting a single input cap on an amp to filter out below 80hz (book shelf setup) It didnt go well and sounded funky in the lower bass.
With a heat piped you might not need a fan at all, stock it might be overkill.
For bridging 2 3886, check out audiosector.com section here and look at there 4780 config (2 3886 in one package) on wiring for stereo or bridged mono.
DIY Chip Amplifier Kits, PCB's, Components and Information.
With a heat piped you might not need a fan at all, stock it might be overkill.
For bridging 2 3886, check out audiosector.com section here and look at there 4780 config (2 3886 in one package) on wiring for stereo or bridged mono.
DIY Chip Amplifier Kits, PCB's, Components and Information.
That amount of capacitance is fine for the woofer section, but totally unnecessary for the mid and tweeter amps, see previous posts.
Bridging Adapter For Power Amps
Simplest Ever Bridging Adapter for Amplifiers
It is not exactly new. And yes, several people have compared them. You will find some threads with the search function. Usually it turns out to be a question of taste.
Yes, if you build the class H application (it's called high-efficiency application in the datasheet). That means you need a power supply with two rail voltages, e. g. ±20 V and ±40 V.
Thanks for the links Pacificblue. I figured that 40k uf is over kill for the mid/tweet sections. However, I bought them in that configuration so might as well use them. What I might do instead is use one 40k module for both mid/tweet sections. But I am trying to keep any cross talk or other anomalies from intermixing.
I'll take a look at the H class application.
I'll take a look at the H class application.
Tri Wiring 101
Hey guys, I have a pair of 3-ways as to which I am going to run with an active crossover. I'm in the midst of building a dedicated 6ch amp for this purpose. Typically 3 pairs of speaker wire from the amp (for each speaker) are required. Everyone following me so far? ..Now, as we all know cabling is fairly pricey, especially when wiring for a HT
My idea, and it might be stupid or brilliant (I'll let you decide) is to run one 4x14 ga cable per speaker but using the one ground (out of the 4) to supply all three ground terminals and the remaining 3 to supply the discrete woofer/mid/tweeter signal. Simply use "jumpers" to patch the needed ground to the other two drivers.
My reasoning behind this notion is that in a amp, most of the ground is shared. Even in the signal path ...right?
Hey guys, I have a pair of 3-ways as to which I am going to run with an active crossover. I'm in the midst of building a dedicated 6ch amp for this purpose. Typically 3 pairs of speaker wire from the amp (for each speaker) are required. Everyone following me so far? ..Now, as we all know cabling is fairly pricey, especially when wiring for a HT
My idea, and it might be stupid or brilliant (I'll let you decide) is to run one 4x14 ga cable per speaker but using the one ground (out of the 4) to supply all three ground terminals and the remaining 3 to supply the discrete woofer/mid/tweeter signal. Simply use "jumpers" to patch the needed ground to the other two drivers.
My reasoning behind this notion is that in a amp, most of the ground is shared. Even in the signal path ...right?
Re: 14 Ga divided by 3
That's a good point. However, 80% to 90% (approx) of that 100 W power is going to the woofer(s). For the tweeter and midrange, we're mostly fighting the resistance in the 30 foot cable.. so to speak.
Re: Monoblocks behind the speaker
Unfortunately we're still fighting the cabling issue. With that idea we're now running 3 thirty foot RCA - even pricier cables.
My biggest concern really is the effect on the quality of the signal. Would there be any bleeding or crosstalk between the 3 filtered signals through the shared ground?
That's a good point. However, 80% to 90% (approx) of that 100 W power is going to the woofer(s). For the tweeter and midrange, we're mostly fighting the resistance in the 30 foot cable.. so to speak.
Re: Monoblocks behind the speaker
Unfortunately we're still fighting the cabling issue. With that idea we're now running 3 thirty foot RCA - even pricier cables.
My biggest concern really is the effect on the quality of the signal. Would there be any bleeding or crosstalk between the 3 filtered signals through the shared ground?
?
less copper in the interconnect surely means cheaper cable.
Only one interconnect to the crossover and three short (or none) to power amps must be 5 to 10times cheaper and better immunity from instability than using long speaker cables.
OK:
Option 1: run 30 feet of 14/4 Ga speaker wire from a 6 Ch amp (located at home theatre hub cabinet)
Option 2: run 30 feet of well shielded RCA cabling from the active crossover (HT hub) to 6 monoblocks (3 per speaker)
Cost of 14/4 in wall speaker wire: 60$ for 100 feet.
Cost of 6 thirty foot RCA cabling: 80$ to 100$ each.
Cost of 6 monoblocks (DIY of course): 150$ to 200$ each.
Option 1 cost: 60$ + 400$ (DIY 6 Ch amp) = 460$
Option 2 cost: 6x80$ + 6x150$ = 1080$
Note: I can only locate my system in a cabinet more or less central-side of the HT.
At less than half to a third (more likely) than discrete monoblocks and cabling, I'd rather take my chances with minor increase in distortion and deviations from room and other electronic interferences. At the end of the day, would the difference be actually audible..?
Also, I've heard (but never measured first hand) that long speaker runs are better than long RCA cabling runs. What do you guys think?
Option 1: run 30 feet of 14/4 Ga speaker wire from a 6 Ch amp (located at home theatre hub cabinet)
Option 2: run 30 feet of well shielded RCA cabling from the active crossover (HT hub) to 6 monoblocks (3 per speaker)
Cost of 14/4 in wall speaker wire: 60$ for 100 feet.
Cost of 6 thirty foot RCA cabling: 80$ to 100$ each.
Cost of 6 monoblocks (DIY of course): 150$ to 200$ each.
Option 1 cost: 60$ + 400$ (DIY 6 Ch amp) = 460$
Option 2 cost: 6x80$ + 6x150$ = 1080$
Note: I can only locate my system in a cabinet more or less central-side of the HT.
At less than half to a third (more likely) than discrete monoblocks and cabling, I'd rather take my chances with minor increase in distortion and deviations from room and other electronic interferences. At the end of the day, would the difference be actually audible..?
Also, I've heard (but never measured first hand) that long speaker runs are better than long RCA cabling runs. What do you guys think?
cat5 cable has 4pair. This @ ~10cents/foot will take all three channels from a centrally located active filter box to the remote monoblocks.
Your cat5 cost is two 30feet runs ~$6
You could use the same Cat5 from the spare still in the box ($50/1000') for the six 2feet runs from monoblocks to speaker drivers.
In my opinion the CAT5 used for both short speaker leads and long interconnects at line level will allow the amplifiers to perform better than any type of long speaker cables and short or zero interconnects.
Your cat5 cost is two 30feet runs ~$6
You could use the same Cat5 from the spare still in the box ($50/1000') for the six 2feet runs from monoblocks to speaker drivers.
In my opinion the CAT5 used for both short speaker leads and long interconnects at line level will allow the amplifiers to perform better than any type of long speaker cables and short or zero interconnects.
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Go balanced for long runs - neither a long speaker run nor a long RCA connection is a good idea if sound quality is a requirement. Like Andrew says, twisted pairs are the way to go both for cheapness and sound quality. Be aware though that long runs may encounter significant ground differences so will require a ground wire in addition to the two signals. STP is one way of getting the extra wire even though the screening isn't really worth having.
I've done some quick reading here and there and sounds like the CAT5 twisted pair(s) are the way to go. Even as a long run speaker cable, the positive claims are for the CAT5. Very interesting. I wish I had asked you guys BEFORE buying a spool of 14/4 in-wall speaker cable. Damn!
Here's an interesting site on the subject:
DIY Cat5 Speaker Cables
I still have to decide on the discrete monoblocks at speaker versus a single multi channel amp at central-side location.... Yes, cost still being a major driver. What to do, what to do..
What I'm considering right now as an intermediate, since I'm redoing my HT from scratch - walls, ceilings et al, is to run 3 CAT5s from the main system (per speaker) and have the flexibility later to either run them discretely with monoblocks or maintain the old way of 30 foot amplification. Which means I'll have to now run extra 14/2 electrical wiring with receptacles for each speaker - on their own separate 15 amp breakers. Well, for the front 2 mains and center speaker.
You guys are making me work harder
Here's an interesting site on the subject:
DIY Cat5 Speaker Cables
I still have to decide on the discrete monoblocks at speaker versus a single multi channel amp at central-side location....
Yes, cost still being a major driver. What to do, what to do..What I'm considering right now as an intermediate, since I'm redoing my HT from scratch - walls, ceilings et al, is to run 3 CAT5s from the main system (per speaker) and have the flexibility later to either run them discretely with monoblocks or maintain the old way of 30 foot amplification. Which means I'll have to now run extra 14/2 electrical wiring with receptacles for each speaker - on their own separate 15 amp breakers. Well, for the front 2 mains and center speaker.
You guys are making me work harder
If you haven't bought your Cat5 box yet, check out Cat6. The wire gauge is a little thicker (23AWG vs 24AWG) so will give a slight improvement when run as speaker cable. For signals, I think the noise rejection will be slightly better too.
Alright, here's what I've decided to do:
The LM3886 DIY 6ch amp that I'm working on will be split in two 3ch amps for each L/R speaker. Run dedicated 14/2 electrical wire with own 15A breaker to supply the amps. Run 3 CAT6 UTP - twisted together as one cable to supply 3-way line level signal from my Behringer DCX 2496 and subsequent ADA processor. The CAT6 cables will have to be min 30 foot runs. I'll have to fabricate a motorized twisting mechanism to make my life easier. I may end up making 5 of these cables for the 5.1 system. Way too much twisting for my little fingers.
Anybody see any problems here so far?
Now, here's my question 1:
The DCX 2496 has XLR interconnects. Is there truly a good advantage to go through the trouble of keeping to whole line level signal balanced? If so, then I'll have to make amps inputs accordingly.
And question 2:
In the 4 twisted pairs; is there a preference or technique for proper XLR interconnects wiring? E.i: which one to use as ground wire..
The LM3886 DIY 6ch amp that I'm working on will be split in two 3ch amps for each L/R speaker. Run dedicated 14/2 electrical wire with own 15A breaker to supply the amps. Run 3 CAT6 UTP - twisted together as one cable to supply 3-way line level signal from my Behringer DCX 2496 and subsequent ADA processor. The CAT6 cables will have to be min 30 foot runs. I'll have to fabricate a motorized twisting mechanism to make my life easier. I may end up making 5 of these cables for the 5.1 system. Way too much twisting for my little fingers.
Anybody see any problems here so far?
Now, here's my question 1:
The DCX 2496 has XLR interconnects. Is there truly a good advantage to go through the trouble of keeping to whole line level signal balanced? If so, then I'll have to make amps inputs accordingly.
And question 2:
In the 4 twisted pairs; is there a preference or technique for proper XLR interconnects wiring? E.i: which one to use as ground wire..
the CAT5 already has the pairs twisted, there's no need to do any more twisting.
Just use three of the pairs to send three independant signals.
In a balanced system, the ground wire is NOT referenced to the signals.
The two signals are referenced to each other and the differential amplifier reads the difference between the two signal wires and either sends that on as a balanced signal or converts it to single ended and sends it on as a signal and signal ground.
Just use three of the pairs to send three independant signals.
In a balanced system, the ground wire is NOT referenced to the signals.
The two signals are referenced to each other and the differential amplifier reads the difference between the two signal wires and either sends that on as a balanced signal or converts it to single ended and sends it on as a signal and signal ground.
Thanks for clearing that up Andrew. Much appreciated.
I had concerns of running even a line level signal through a pair of 24 Ga over 10 Meters. Reason why I was going to dedicate one whole CAT cable per signal. But if your experiences are telling me to use 3 pairs out of the CAT cable, then I shall do so. Could always upgrade later if need be.
My last concern about this arrangement is the difference in length between the 2+2 pairs. Two are more twisted than the other. Will there not be a lag in transmission time? However, that being mentioned, I shall use 2 identically twisted pairs for the tweeter and midrange. Use the less twisted for the woofer. Since all 3 drivers are lined up on the same baffle plane, this might give me a better time alignment.
I had concerns of running even a line level signal through a pair of 24 Ga over 10 Meters. Reason why I was going to dedicate one whole CAT cable per signal. But if your experiences are telling me to use 3 pairs out of the CAT cable, then I shall do so. Could always upgrade later if need be.
My last concern about this arrangement is the difference in length between the 2+2 pairs. Two are more twisted than the other. Will there not be a lag in transmission time? However, that being mentioned, I shall use 2 identically twisted pairs for the tweeter and midrange. Use the less twisted for the woofer. Since all 3 drivers are lined up on the same baffle plane, this might give me a better time alignment.
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