On the topic of amplifiers.
Have you seen these post over at avs?
Lab Gruppen FP14000 clone amplifiers
WOAH, it's official, the FP10000Q has audiophile-quality top end (this is a BIG DEAL!!!)
Nice to have some cheap power if you want to make your 18sw115 move some air..
Have you seen these post over at avs?
Lab Gruppen FP14000 clone amplifiers
WOAH, it's official, the FP10000Q has audiophile-quality top end (this is a BIG DEAL!!!)
Nice to have some cheap power if you want to make your 18sw115 move some air..
Dave,
The XOC1TH-18 does fine to about 35 Hz, and can still be EQed to just above 30 Hz.
Most bass has as much first harmonic as fundamental, so you will "hear" 16 or 20 Hz tones when the cabinet plays the 32 Hz or 40 Hz harmonic. That does not happen with many (most) DJ kind of "subs" , which come in at 50 Hz.
There is no "k" in circuit
, but a 15 amp circuit in good shape can provide an average of 1800 watts.As mwmkravchenko pointed out, most breakers can withstand short peaks of 10 times their rating.
Getting back to the average rating of 1800 watts, let us say your squashed compressed bass heavy music has only 10 dB dynamic range (2 dB less crest factor than pink noise), you could potentially run 100% efficient amps capable of 18,000 watt peaks on a single 15 amp circuit without exceeding the average power rating of the 15 amp circuit.
Amps are usually in the 60-85% efficiency range, subtract peak power of your particular amp combination efficiency rating.
In the real world, a 15 amp circuit can legally (in at least some jurisdictions) be run using 14 AWG wiring.
So what is the voltage drop of 18,000 watts (150 amps at 120 volts) on 150 feet of 14 AWG?
Voltage Drop Calculator
Oops, the voltage has dropped to only 51.6 volts on those peaks, not good, kick drum fans.
However, if that same 15 amp circuit wired with 14 AWG was located just under the main breaker box, totaling only 4 feet of wire (2 feet out from the hot breaker, two feet back to neutral) the voltage would hardly drop at all- 118.2 volts would be the minimum with 150 amp draw.
Breakers are subject to wearing out, and some are not up to spec to start with, I once had a batch of 20 Amp Square D breakers (normally a very good brand) that would trip when a single amplifier was turned on.
Breaker sensitivity, what other stuff may be plugged in to the same circuit (12 amp coffee makers, lights, random microwave use, etc.) coupled with type of music, length and gauge of wire, and amplifier efficiency, make it impossible to give a “one size fits all” answer to your question.
That said, always best to plug in your own 12 or 10 AWG cords as close to the main breaker box as possible if you want to get the most dynamics out of your system.
Art Welter
Thanks for the info Art. I figured there wasn't a "standard" answer but that gets me some basic understanding. It means I could run a PLX3602 on highs and something as big as the I-Tech 8000 that neo dan was talking about, both at 4 ohn stereo, at reasonable volume with compressed bass and considerably higher with dynamic "music" before tripping a 15 amp breaker as long as it is the only thing on that circuit and the wire length/gauge are ok.
Sorry, I work for the local phone company and unless its a POTS (plain old telephone service) line we refer to it as a ckt (circuit)
There is no "k" in circuit
Art Welter
Sorry, I work for the local phone company and unless its a POTS (plain old telephone service) line we refer to it as a ckt (circuit)
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And the breaker is good, and your "music" has less average power than "1/8th power pink noise", usually not a problem with live music, but for some reason (massive clipping at every gain stage cough cough), often not the case for recorded music run by many DJs
.As you can see, the I-T 8000 will draw 35.1 amps if you lean on it at 4 ohms.
The QSC PLX 3602 alone will draw 40 amps at 120V with a full power sine wave signal (for around one second before tripping it's own breaker), but "only" 11.5 amps at 1/8th power pink noise, and 19.5 amps 1/3 power pink noise at 4 ohms.
But again, with a single stiff 20 amp 120 VAC line, I have run two PLX 3602 and four Crest CA-9, all with clip lights flashing from time to time.
All depends on the "music".
Art
Attachments
Yeah that about sums it up...SO... REW on my Mac=
Make the built in sound the default input device and ditch the FW box entirely or only use it for output and mic preamp duty, route the mic signal back to the Mac through the mic/headphone jack. You could even just use the SPL meter if it has a 1/8" output, you'll probably need a mono cable though.
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Sounds correct since maximum excursion occurs ~45-50Hz for the drivers I've looked at. What were you expecting?
The spl to displacement figures may be quite accurate, but the fact I like to remember is that real world compression (dynamic and thermal) affect both. In other words, the spl and displacement in hornresp may be achieved in real life, but at a higher input voltage. There's quite a bit of info regarding compression types and how they affect output in this thread.
That's what I was pondering.
Then we have cone correction to help control excursion. And peak displacement which is usually more than xmax.
Offsetting the extra carbs with fiber I see... ; )
At least you got something cold to wash down the dust.
Nice work. Now that you have the two variations I can't wait to hear your opinion of it. Would guess that the if the new box has similar S1-S2 volume, it will sound pretty close. Hopefully this one will go a little lower though.and a GOOD OKTOBER to you all !
My newest pile of saw dust,,,,,,
At least you got something cold to wash down the dust.
Hi Dan,
Yes it will be a fun comparison,The first one is running good ,The second one has a lot of changes and well experimental,Let's hope it Loves to rumble,I had a lot of help from all the members here good Ideas, Thanks !
I do hope it will go lower and give good bass !
A few good beers are good for your piece of mind ! Music sounds better sometimes too,lol.
Yes it will be a fun comparison,The first one is running good ,The second one has a lot of changes and well experimental,Let's hope it Loves to rumble,I had a lot of help from all the members here good Ideas, Thanks !
I do hope it will go lower and give good bass !
A few good beers are good for your piece of mind ! Music sounds better sometimes too,lol.
good joband a GOOD OKTOBER to you all !
My newest pile of saw dust,,,,,,
looks like a solid bild.
im intrested also in a 1 to 1 comparison with the mk1.
shake it baby.
Hi Epa,
well It's making music,The second build or the one pictured above needs break in time ,I did get REW going and did some newbie tests on The first build and it looked much flatter and the dips where gone ,it has 2 rings on the outside of the throat and one ring on the smaller side They are attached to #8 Panel in the drawing,that's working the best so far for me and using this speaker B&C 18PBZ100 more to come,Comments on build or REW are welcome ! I'll post some captures when I feel I have them accurate,
Happy Listening !
NS
well It's making music,The second build or the one pictured above needs break in time ,I did get REW going and did some newbie tests on The first build and it looked much flatter and the dips where gone ,it has 2 rings on the outside of the throat and one ring on the smaller side They are attached to #8 Panel in the drawing,that's working the best so far for me and using this speaker B&C 18PBZ100 more to come,Comments on build or REW are welcome ! I'll post some captures when I feel I have them accurate,
Happy Listening !
NS