I have mixed feelings about Chinese products. Lot's of slave labor in China but quality is improving. I was bugged by the trademark infringement but at this point there are some Chinese knock off guitars I would not feel guilty about owning. Gibson has been crappy for and overpriced for decades but now even Peavey is making its stuff in China.
Amps generally can handle a 4 ohm load. I have a vintage Ampeg V-4B that has an impedance switch that goes from 8 - 4 and 2 Ohms. I'd be inclined to risk it. Besides the amps are probably fused. I fuse my horns. Not sure about class D amps but most amps are safest with a high load. I have a good tech. I've heard that Behringer quality has improved.
A 3 channel amp makes sense. 1200 watts for the low end and 400 for the tops and the monitors.
I only see 2 speaker outputs.
I have power amps and a couple of 15" Black Widows.
Amps generally can handle a 4 ohm load. I have a vintage Ampeg V-4B that has an impedance switch that goes from 8 - 4 and 2 Ohms. I'd be inclined to risk it. Besides the amps are probably fused. I fuse my horns. Not sure about class D amps but most amps are safest with a high load. I have a good tech. I've heard that Behringer quality has improved.
A 3 channel amp makes sense. 1200 watts for the low end and 400 for the tops and the monitors.
I only see 2 speaker outputs.
I have power amps and a couple of 15" Black Widows.
+1 on that, theft of intellectual property is always a bad thing but on the other hand... this isn't news, they have been doing that for decades... perhaps much longer, so the companies that moved production over there to maximize their profits knew what they were getting into.
I have purchased quite a bit of LED stage lighting from this site, I picked items that don't appear to be direct copies of domestic products but still had desirable features. These are not cheap junk products either, the last units I bought cost $500ea and have performance similar to a $2000 brand name product, and in all cases these things perform great. Some of these fixtures have hundreds of hours on them now with no failures, so it is possible to get good products from China. I have not purchased any audio products from here yet but there is a line of class D amplifier that is gaining quite the reputation in some markets, so I'm really tempted. You should note that any item you see on this or any other China site with a well known brand name on it is counterfeit, no exceptions.
Yes, but powered speakers will typically have 4ohm or even 2ohm drivers in them already.
Yes, this amp module would normally be mounted in the sub enclosure and that driver is powered by an internal connection on the amp module.
There are other modules available with other configurations, some designed for bi-amping a single speaker cab for example and others large enough to drive a pair of drivers at 4ohms.
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I have a lot of time to figure this out. Maybe by October 2021 some venues will open. From time to time I check Craig's List for used gear.
I can only guess what the music scene will be when this is over. It's gonna take time. I wonder what the manufacturers are thinking and planning. I'm not seeing any discounts.
I can only guess what the music scene will be when this is over. It's gonna take time. I wonder what the manufacturers are thinking and planning. I'm not seeing any discounts.
" Yes, but powered speakers will typically have 4ohm or even 2ohm drivers in them already."
yes, and some use drivers with dual voice coils, which isnt ideal when trying to fudge an output to another driver.
Honestly, given how cheaply you can buy amps (especially second hand) with enough oomph to drive several passive subs I don't see the logic behind abusing an active speaker and risk over heating the amplifier unit.
yes, and some use drivers with dual voice coils, which isnt ideal when trying to fudge an output to another driver.
Honestly, given how cheaply you can buy amps (especially second hand) with enough oomph to drive several passive subs I don't see the logic behind abusing an active speaker and risk over heating the amplifier unit.
Back in the olden days, Carvin sold powered speakers and un-powered "slaves". As long as an amp is seeing the correct load, I'm thinking the amp will be fine. Amps are cheap but in a case where you need a lot of subs we're looking at a lot of AC current draw if all the subs are powered.
In another thread I discussed battery powered amps for big sound reinforcement application. Car amps are essentially battery powered amps. Transformers are the most expensive part of most amps. Pro sound companies use generators.
Power surges and voltage drops probably damage more amps and speaker than any other cause.
In another thread I discussed battery powered amps for big sound reinforcement application. Car amps are essentially battery powered amps. Transformers are the most expensive part of most amps. Pro sound companies use generators.
Power surges and voltage drops probably damage more amps and speaker than any other cause.
Increasing the load on an amp won't hurt it. A good tech can modify an amp for the better. If you upgrade parts such as caps, transistors and resistors the amp will be better. Chinese made amps often use crappy components.
If I were to upgrade a powered sub with a high efficiency driver, it will be better. If the amp was designed for a 4 ohm load an Ohm load won't hurt it. If another 8 Ohm drive is added in parallel the amp with see the 4 Ohm load for which it was designed.
If the speakers are more efficient the amps won't have to work as hard to achieve the same SPLs.
I'd have no worries turning a powered sub into a master sub with a satellite slave speaker. As long as the amp sees the correct load it will be okay. Really.
It doesn't matter if the speakers are powered or passive but all powered speakers manufactured in the last decade use class D amplifiers and switch mode power supplies. This combo is much more energy efficient than traditional versions, in some cases the modern combo can produce the same output with less than 1/2 the AC current draw. This design still uses a transformer but it is tiny so the whole amp is a fraction of the weight or a classic design. The 750w DSP equipped plate amp in some of the powered speakers I own weighs 4lbs.
Not so much any more, many of these modern amplifiers automatically adjust to any AC supply between 90-250v making them suitable for use anywhere on the planet and all but the worst generator.
Good point.
Clean power is an issue as is current draw. Modern class D amp sound good though some audiophiles may not agree. Less weight and low current draw are are important and like you said, powered subs are cost efficient. Having extra ones ensures redundancy and scalability.
Clean power is still important and low voltage can be a problem that affects some amps more than others. When you play in a club, power can be a problem. There can be bad grounding, surges and line noise. It's best to run heavy gauge power cords to reduce voltage drops. Power conditioners can help.
Clean power is an issue as is current draw. Modern class D amp sound good though some audiophiles may not agree. Less weight and low current draw are are important and like you said, powered subs are cost efficient. Having extra ones ensures redundancy and scalability.
Clean power is still important and low voltage can be a problem that affects some amps more than others. When you play in a club, power can be a problem. There can be bad grounding, surges and line noise. It's best to run heavy gauge power cords to reduce voltage drops. Power conditioners can help.
One thing that has become a new requirement for live sound systems is battery backup for the digital devices, but luckily a small UPS is all that is required in most cases as powered speakers and DSP amplifiers don't need the added protection. Digital devices can become corrupted or damaged from unintentional power loss or brownouts, or at the very least you might lose all the work you did dialing in a band at soundcheck. Also if a mixer or digital stage box power cycles with the sound system on this often sends a massive signal spike though the speakers that can be damaging. So a UPS is a pretty standard thing to find in racks these days, they not only protect equipment from over and under voltage spikes(some also do voltage regulation and conditioning) but allow the system to be shut down gracefully(have time to save your work) in the event of total system power loss.
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It will if its already being ragged, which it most likely is if you are abusing your system to squeeze out a bit more noise.
Yes, but then you are mucking about with putting drivers into cabinets they weren't designed for.
All this replacing drivers / updating components etc etc might be fun and possible but doesn't seem like time / money well spent to me. Just buy another amp, job done.
A good tech will also know when not to interfere with something that's working as intended.
lose low-frequency extension due to Hoffman's Iron Law.
... Except a modern powered subwoofer will have DSP that's specifically set up to get the most out of the exact driver that's installed at the factory. Correct EQ, correct limiting (RMS, peak, sometimes thermal tracking), correct crossovers.
It's not just about matching impedances.
... Definitions of "okay" vary. Will it make noise? Probably.
Swapping drivers in the name of "higher efficiency" will likely result in sub-par LF performance: when comparing drivers, subwoofer drivers will often have lower sensitivity than midbass drivers. When properly driven, though, the subwoofer drivers will often be capable of considerably more LF output, because they have much more linear excursion.
Active speakers have moved on from the days of class AB amps with 12dB/octave filters strapped to the back of a cabinet.
Take a look at what Powersoft or Linea Research are up to in terms of their amplifiers and processing for an idea of what can be done.
Chris
We ran into low voltage situation on several occasions. The thing that was affected most was the keyboard.
Batteries make sense for running everything. Current from the venue can keep batteries topped off topped off. Battery technology advancing. I think the Tesla truck can provide AC power for the worksite.
Wedding DJ would love it. Running extension cords is a pain in the butt.
The technology exists to do this now. I don't think weight will be an issue. I think the cost will be recouped by the protection clean stable power provides for the gear.
No I disagree with that, I do a lot of DJ events and also sound on parade floats. Where shore power isn't possible generators are necessary for a sound system of any size or an event of any duration, batteries just don't last long enough or have enough output capacity for larger systems. Battery powered speakers are a good option for remote wedding ceremony's though, and there are a lot more options in that category every day.
A little bit of a swerve that underlines the point about battery life. I also do a lot of special effects lighting at weddings and other events and the vast majority of my LED lighting is AC powered only. I do have some battery powered lighting that has been useful in some situations but for most events the batteries just don't last long enough to make it to the end of an event. That might be acceptable for non critical lighting but it's just not an option for the event's main audio system.
Those Linea Research amps look good. Power output is impressive.
If I recall correctly it takes a doubling of watts to get 1 db of volume. It would seem with their high output even low efficiency high watt handling driver would to the trick.
These Rockville 15's claim an SPL of 100db at one Watt. https://www.amazon.com/Rockville-RVP15W8-2000-Subwoofers-Woofers/dp/B00IK6VYH4/ref=pd_sbs_267_2/139-1177336-5233507?_encoding=UTF8&pd_rd_i=B00IK6VYH4&pd_rd_r=06b913d5-b40f-4dee-b2c8-efbb42864dba&pd_rd_w=IiByh&pd_rd_wg=ojlUv&pf_rd_p=ed1e2146-ecfe-435e-b3b5-d79fa072fd58&pf_rd_r=VKAE9D01HGQ80JN3N3RN&psc=1&refRID=VKAE9D01HGQ80JN3N3RN#customerReviews
What I don't understand is how they can sell 2 of them for 90 bucks. They have a frequency response of 25hz to 1500hz. They claim to have 1000 watt RMS power handling.
I guess I'm not understanding why a speaker upgrade could cause problems since the DSP (Digital Signal Processor) has no way of knowing what speaker the amp is driving when the amp is seeing the same load as it did with the original speaker. It can't detect cone travel.
How can upgrading to a better speaker of the correct impedance make the amp act differently? Does gain input have a different affect of class D amps. My plan is to split the signal with an active crossover before sending it to the subs and sending 0 to 120Hz.
No it's 3dB.
Not for PA applications.. you still want as much SPL capability as possible.
Those things are junk and all of the specs are BS, those things will not meet any of the claimed specs.
It's because you don't realize how integrated the DSP is in some of these speakers, with the better versions it does know how much the cone is travelling or how hot the voice coil is, that is the magic of powered speakers they have the potential for a level of integration and feedback that isn't possible any other way, and even in the lesser versions the DSP parameters have been custom tailored to a specific driver to maximize output from the amp, so you're simply not going to get more out of that combo with a different driver.
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I stumbled across this this last night and thought it might be an idea for you, I remember seeing this system years ago and forgot about it but it might be exactly what you want to try to copy.
Carvin TRC400A 4000W Active Column Array System - Carvin Audio
If a driver has similar specs to the one being replaced it will work fine. It ain't rocket surgery. Manufactures don't always use the best components.
I've replaced many woofers in various cabinets as replacements and upgrades over the years and in every case it was an improvement.
Thiele/Small Parameters Explained. A beginner's guide.
Tuned port cabinets are more critical than other designs but most powered subs are vented boxes with front facing woofers. A good configuration would be to add a medium throw cabinet or a band pass box.
The systems today are often geared to DJs who play recorded music. Live music is very different. It's much more dynamic. In the beginnings of amplified music the innovators were the musicians.
46 Years Ago The Grateful Dead Debuted "The Wall of Sound" And Changed Live Music Forever ~ LIVE music blog
The Grateful Dead figured out how to have the PA behind them and not get feedback.
“The Wall of Sound is the name some people gave to a super powerful, extremely accurate PA system that I designed and supervised the building of in 1973 for the Grateful Dead. It was a massive wall of speaker arrays set behind the musicians, which they themselves controlled without a front of house mixer. It did not need any delay towers to reach a distance of half a mile from the stage without degradation.” – Owsley “Bear” Stanley