Anyone got a Behringer EP2500?
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From: Bob Howes on 11 Feb 2007 07:50 "hank alrich" <walkinay(a)thegrid.net> wrote in message news:1htbfs8.12nfpgnkkuaemN%walkinay(a)thegrid.net... > > OTOH, failing to mention, in all the laudatory posts about the amp, that > it thumps on powerup/down, represents something less than full > disclosure. > I can't speak for the others but in my case the lack of mention is because the switch-off thump is far from memorable, and no worse than a whole slew of other name-brand (but economy) amps. Bob
From: Bob Howes on 13 Feb 2007 14:59 "Bob Urz" <sound(a)inetnebr.com> wrote in message news:1171125515_4877(a)sp6iad.superfeed.net... > > > > I think the issues come up if you are bi or tri amping. The compression > drivers will handle the power in there frequency range. But a full > bandwidth transient could take out a driver diaphragm. There is no > guarantee that during a power blip that the digital filter sections will > continue to filter until the PS caps drain. and no passive crossovers to > protect you at the speaker end. This is where the mute would > have been a good feature > Good point, and just to confirm: when the incident I mentioned above blew some drivers for me, I was running in bi-amp mode. I suspect you're onto something with your theory. Bob
From: Earl Grey on 13 Feb 2007 15:54 On Tue, 13 Feb 2007 19:59:31 +0000, Bob Howes wrote: > > "Bob Urz" <sound(a)inetnebr.com> wrote in message > news:1171125515_4877(a)sp6iad.superfeed.net... >> >> >> >> I think the issues come up if you are bi or tri amping. The compression >> drivers will handle the power in there frequency range. But a full >> bandwidth transient could take out a driver diaphragm. There is no >> guarantee that during a power blip that the digital filter sections will >> continue to filter until the PS caps drain. and no passive crossovers to >> protect you at the speaker end. This is where the mute would >> have been a good feature >> > > Good point, and just to confirm: when the incident I mentioned above blew > some drivers for me, I was running in bi-amp mode. > > I suspect you're onto something with your theory. > > Bob Its worth having a ~47uF capacitor in series with your horns in active boxes to guard against high excursion signals post the crossover filtering.
From: Eeyore on 14 Feb 2007 01:05 Bob Howes wrote: > "Bob Urz" <sound(a)inetnebr.com> wrote in message > > > > I think the issues come up if you are bi or tri amping. The compression > > drivers will handle the power in there frequency range. But a full > > bandwidth transient could take out a driver diaphragm. There is no > > guarantee that during a power blip that the digital filter sections will > > continue to filter until the PS caps drain. and no passive crossovers to > > protect you at the speaker end. This is where the mute would > > have been a good feature > > > > Good point, and just to confirm: when the incident I mentioned above blew > some drivers for me, I was running in bi-amp mode. HF drivers ? They should *always* be capacitively coupled for safety. Graham
From: Rupert on 14 Feb 2007 21:36
On Feb 13, 10:05 pm, Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: > Bob Howes wrote: > > "Bob Urz" <s...(a)inetnebr.com> wrote in message > > > > I think the issues come up if you are bi or tri amping. The compression > > > drivers will handle the power in there frequency range. But a full > > > bandwidth transient could take out a driver diaphragm. There is no > > > guarantee that during a power blip that the digital filter sections will > > > continue to filter until the PS caps drain. and no passive crossovers to > > > protect you at the speaker end. This is where the mute would > > > have been a good feature > > > Good point, and just to confirm: when the incident I mentioned above blew > > some drivers for me, I was running in bi-amp mode. > > HF drivers ? > > They should *always* be capacitively coupled for safety. > > Graham They may have been true in the past, but it's rare you find blocking caps on HF horns in high end, high SPL boxes these days. The HF drivers are usually wired direct. In high SPL applications, series caps on HF compression drivers can actually create IM distortion due to the adjacent LF driver pressure wave actually moving the compression driver's diaphragm since a cap will decouple the damping action of the amp's output terminals. Granted, in lower power situations this is likely a non issue. But in high output boxes the distortion is measurable and in the case of the TAD 4000 series drivers, the motion is enough to shatter the diaphragm again the phase plug since their expensive beryllium diaphragms have a higher compliance surround. For this reason EAW removed the series caps from the TAD version of the KF850, or at least installed a choke in parallel depending on what a client opted for, and the issue was solved. I know of at least one other user of that driver that had to remove the cap for the same reason. Rupert |