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inferno

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so my trusty behringer ep1500 died a few days ago. it was a straight up copy of a qsc amp down to the board. i think it delivered 2x200 or so W at 8 ohms. i used it bridged for a peerless xls 10 incher 2 ohm (prototype) for about 2-3 years with the fan unhooked :) and after maybe 30 minutes it would cut out and it smelled like burnt transistors.

but now for the last 2 years i have been very kind to the amp. i built a new bassbox, now it sees 8 ohms per channel. but still i didn't want that jet plane fan running 24/7. but now last week it just died. dafuq...

and to be honest i dont know if its worth fixing. i basically fried it for several years. and i knew i was doing this.

---------------

so now i'm looking for a new amp. preferably some cheaper but good studio amp. maybe (real) 2x200W@8 ohm or more. preferably no class D/pwm ****. preferably real analog class a/b. i think i can pay 500€ for this. the behringer was like 200€. and the real qsc was about 1 grand. not getting a real qsc though. nor a bryston...

i'm overheating my backup NAD 2x40 watter now fairly easily. so i need beefier than this. maybe 10db hotter.

any brands to look into? what do you recommend?
 

GoodMagic

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Get an old hafler dh200 or old classe. Tons of good old audio gear around.
 

inferno

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i dont know if i want to get an old one. if i burn out a new one in like 2 years or less i have warranty.

but yeah of course you are right about used stuff. it cost like 10% of new. no cheap brystons though.

my brother had a hafler.

i want the juice so i can play loud. my woofers have the capacity for about 120db or so at 20hz. +-3cm stroke linear, and then double distorted. so they move lots of air. and i run 2 now. the distortion at 20 hz is very low, i think someone measured them at less than 1% at xmax. and he was a real engineer/physicist that actually design speakers for a living. thats good enough for me.

now i need to feed these babies. they eat electrons.
 

Bill13

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How about a used Bryston? A 20 year warranty is tough to beat, and Audiogon is your friend with the usual caveats.
 

gregfisk

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I know you said no class D but bang for buck and on your budget you can't beat a Crown XLS1500. It will run circles around your Behringer. You will not burn up the Crown either as they are stable down to 2 ohms and they have a ton of power. I have an old Hafler which I love the sound of and they are also work horses but they are hard to find for the kind of money you want to spend. I'm a hard core audiophile who has been taking a break after a dear friend and fellow audiophile took his own life. That's why I've gotten into knife making. Well that and I retired and needed something else to do.
 

panda

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How about a used Bryston? A 20 year warranty is tough to beat, and Audiogon is your friend with the usual caveats.
brystons are great but not exactly budget friendly. he's talking about NAD which are like victorinox of amps.
 

inferno

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so. i have been running the nad 2x40w for a few months. and while its ok. when i want some real juice it will simply overheat in about 2-3 minutes. i have a feeling the nad can deliver several 100 watts for about 1,5 minutes though. but in the long term over lets say a full tune. maybe i want to hear a full electronic tune (6-10min) at full blast. well then the nad cant deliver. i can deliver for a minute though.

i think i have decieded on getting the exact same amp that the behringer was copied from. but now the real deal.
its just 4x as expensive.... RMX 1450a

yeah gonna get that for the bass. yeah i ran the behringer with the fan cable detached for maybe 4 years and it still lasted 4 years. thats good.
-----------

but now i started to reconsider my monitor situation. to be honest i have never been satisfied with my current monitors. i have the jbl 305's
and while these are good if youre coming from computer speakers. i came from dual 6,5 inchers in each box as monitors. so the jbls i feel they compress the sound when playing loud and they also sound very uninspiring. and dull. i think it has to do with their pwm/class D amps, almost 99% sure it it is.

i mean with my old speakers, the "mains" 2x6,5 inch and alu tweeters. 60 liter enclosures, i could play as loud as i managed to hear it. the speakers were not the limiting factor (with the nad 2x40w amp). and i think i simulated them to like 10db lower than the jbls max spl (yeah right), as "max spl". but these actually play loud without distorting nor compressing. so in reality they play louder since they are clean.
----------

so now i have to build new mains too. **** that jbl ****. **** it. its not clean/good enough and its definitely not clean enough at high spl.

i'm gonna go with a slit cone scan speak hemp cone woofer (or dual) woofers, and then probably the older scan speak alu dome full size tweeter.
yeah now were ****ing talking.

i bought a measurement mic, a really good one. QTC50 — Earthworks Audio
you can put this mic inside the box if you want, i like that.

yeah, well, its gonna be some redecorating going on here. and its gonna kick ass!
 

gregfisk

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If you’re talking about getting another class D amp you owe it to yourself to look into the crown xls1500 I mentioned earlier in this thread. They are very stable and and can handle even the heaviest loads. They sound a LOT better than the Behringer amps and best of all.....wait for it..........no fan! They are dirt cheap used since the new version came out a couple of years ago now, the xls1502. My understanding is that they don’t sound any better but I’ve not heard them.
 

WildBoar

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What price range are you looking in? I know of a pair of ~25-year-old Bryston amps for sale in the DC area. They are 40 WPC if I remember correctly, but bridged (used as monoblocks) they are 100 WPC. They are listed for $600 for the pair. One has a slightly hissing transistor that is reportedly just slightly audible if no music is playing. Bryston is great to deal with if someone wanted to send the amps in for overall inspection and any needed minor repairs or updating. I sent in a 21-year-old 4BST a couple years ago that got fried by power spikes and they did the repairs and updated it to as new as they could (one step below the current model at the time) for about $750, including shipping. And that was when the US dollar was a bit weaker compared to the Canadian dollar.
 

turko

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Check out Monopices Monolith series. Word is they're made by ATI and are solid.
 

BazookaJoe

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Not sure why you don't want a class D. I've done a lot of research lately when I needed to replace an amp I had that failed. The class d technology has come a long way. This amp tested very good and for the price per watt, can't be beat.


 

Bobby2shots

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so. i have been running the nad 2x40w for a few months. and while its ok. when i want some real juice it will simply overheat in about 2-3 minutes. i have a feeling the nad can deliver several 100 watts for about 1,5 minutes though. but in the long term over lets say a full tune. maybe i want to hear a full electronic tune (6-10min) at full blast. well then the nad cant deliver. i can deliver for a minute though.

i think i have decieded on getting the exact same amp that the behringer was copied from. but now the real deal.
its just 4x as expensive.... RMX 1450a

yeah gonna get that for the bass. yeah i ran the behringer with the fan cable detached for maybe 4 years and it still lasted 4 years. thats good.
-----------

but now i started to reconsider my monitor situation. to be honest i have never been satisfied with my current monitors. i have the jbl 305's
and while these are good if youre coming from computer speakers. i came from dual 6,5 inchers in each box as monitors. so the jbls i feel they compress the sound when playing loud and they also sound very uninspiring. and dull. i think it has to do with their pwm/class D amps, almost 99% sure it it is.

i mean with my old speakers, the "mains" 2x6,5 inch and alu tweeters. 60 liter enclosures, i could play as loud as i managed to hear it. the speakers were not the limiting factor (with the nad 2x40w amp). and i think i simulated them to like 10db lower than the jbls max spl (yeah right), as "max spl". but these actually play loud without distorting nor compressing. so in reality they play louder since they are clean.
----------

so now i have to build new mains too. **** that jbl ****. **** it. its not clean/good enough and its definitely not clean enough at high spl.

i'm gonna go with a slit cone scan speak hemp cone woofer (or dual) woofers, and then probably the older scan speak alu dome full size tweeter.
yeah now were ****ing talking.

i bought a measurement mic, a really good one. QTC50 — Earthworks Audio
you can put this mic inside the box if you want, i like that.

yeah, well, its gonna be some redecorating going on here. and its gonna kick ass!
Why don't you get yourself a half decent powered subwoofer, and off-load the bottom-end (low frequencies <100Hz) to THAT unit. Sure beats putting up with"burnt-transistor smell",,, or high-spl for "a few minutes". Subs are omni-directional, and you can use a single sub, placed anywhere in the room, without directionality. You can also increase your spl (sound-pressure level) by placing it in half-space, or quarter-space, or eighth-space location, etc. without the need for a more powerful amp. Efficiency is the name of the game.

Look around, and see if you can find a Yorkville Sound NX700P or LS 700P,,, or if you really wanna go nuts on SPL, a Yorkville LS801P.
 

inferno

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I am running a separate subwoofer. and separate active crossover. is has 2 10 inchers. back to back. and the drivers are good. there is 25-30mm xmax or similar on tap linear one way. they are quite efficient in box, in room. i get 2 reflections so that is 6db extra.
 

Bobby2shots

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I am running a separate subwoofer. and separate active crossover. is has 2 10 inchers. back to back. and the drivers are good. there is 25-30mm xmax or similar on tap linear one way. they are quite efficient in box, in room. i get 2 reflections so that is 6db extra.
Bottom line though,,, your present rig is simply not doing it for you. The low-end (100Hz and below) is what's sucking all your "juice",,, HF's (high frequencies) require a LOT less power. Your cross-over won't help here. Use your NAD for the tops ((40w left /40w right) for your smaller speakers.

With a powered sub-woofer, you can run a line-level signal to the sub, which will have its' own active cross-over and power-amp. The sub will probably have a hi-pass filter, which will allow you to run everything below 100Hz,,, or 120Hz, etc, by the subs' built-in power-amp. There will also be a line-out on the sub, and everything above 100Hz, will go to your tops (run by your 2x40w NAD).

What's the application? Are you doing this for home listening? Studio work? Live-sound for bands, etc?

Don't bridge your NAD.
 

inferno

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i have active monitors, 3way xover but running it 2way now, and then an amp and then a passive sub.
basically i fried my good amp. and now i have to use the nad for the sub. which it can do. for a while.
sometimes i think my whole house is a studio.
 

Bobby2shots

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i have active monitors, 3way xover but running it 2way now, and then an amp and then a passive sub.
basically i fried my good amp. and now i have to use the nad for the sub. which it can do. for a while.
sometimes i think my whole house is a studio.
I'm going to go back to the start of this thread and re-read it. I should have read it all in the first place,,,,, my bad.

That said, everything I said so far, applies.

When you say you have "active monitors", what exactly are they?

Also, in post #15, just above, you said you're getting "2 reflections for a 6dB gain". Can you clarify? Are they on stands away from a wall/floor/or ceiling (full-space)? Are they close to the floor(1/2 space)? on the floor next to a wall (1/4 space)? in a corner near a floor or ceiling (1/8 space)? If you're listening at home for example, each reduction in space will give you roughly a 3db gain step-up. That said,,,, if your active monitors are simply firing toward a wall,,,,, then "reflections" can be a bad thing.(time distortion) Depends on how reflective and how large the "room" is.

Also, your Behringer EP1500, is a "Live Sound" amp,,,, that's partially why the fan is so loud. In Live sound applications and environments, fan noise is virtually irrelevent.

I'm curious,,,, where precisely was the "burnt smell" coming from? If it's coming from your speakers, you may have fried the voice-coils. If it's from the amp,,, you probably fried some capacitors. Doesn't your amp have a fuse?
 
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inferno

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well the sub is on the floor, next to a wall. so that gives me some boost.

i have jbl 305s. they kinda suck.

the burnt smell came from the transistors in the poweramp. it usually smelled like that shortly before the thermal shutdown circuits kicked in. that was the signal to connect the fan again. the amp have a fuse and i have not investigated further. the amp it still turns on, it just doesn't provide any power.
 

Lars

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Please don't listen to studio monitors for pleasure. They are not designed for that, but for analytical purposes.
Also, please revisit your opinion of Class D. It can be wonderful when done right, for example the stuff by Bruno Putzeys and Hypex.
 

MarcelNL

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Hypex is good enough for most, you probably want to look at some high efficiency speakers so you can use lower powered amps.
Currently playing with a vintage amp probably not capable of more than 20W p Ch using 4 13" high efficiency broad band speakers (think Klangfilm) in an infinite baffle, 2 Ohm or so per channel, easily loud enough and low distortion and no need for filtering.
 

Lars

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So you don’t like flawless audio reproduction?
 

Bobby2shots

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well the sub is on the floor, next to a wall. so that gives me some boost.

i have jbl 305s. they kinda suck.

the burnt smell came from the transistors in the poweramp. it usually smelled like that shortly before the thermal shutdown circuits kicked in. that was the signal to connect the fan again. the amp have a fuse and i have not investigated further. the amp it still turns on, it just doesn't provide any power.
Inferno, in order to help, I need clear and concise information. I'm still not clear what your set-up is. All I have so far, is your JBL monitors (JBL 305s),,, and your power-amp model (Behringer EP1500).

You've mentioned 2 x 10" speakers back-to-back,,,,, what is that??? Is that what you're using for a subwoofer??? Are those 10" drivers in an enclosure??? You've also mentioned another speaker with 6" speaker with an aluminum tweeter (?????) You've also mentioned a 3-way cross-over that you're currently using as a 2-way. Is that an active or passive cross-over? What's the brand and model?

Cause and Effect:

Bottom line here, you're basically experiencing a type of distortion known as "listener fatigue". This is the root cause of why you're having issues. Basically, it goes like this: your ears and brain have an expectation of hearing sound in a "natural" and predictable balance. The brain "knows from experience" when that "balance" is not "correct",,, the listener makes a "correction" usually by turning up the "missing frequencies or overall volume",,,, and for most home-audio set-ups, that's usually to get the bottom end.(Frequencies below 120 Hz,,, but more typically, below 100 Hz. You then try to "boost" that bass-end by turning up the volume,,,, often resulting in overdriving the mains,,, and adding even more distortion (clipping). When you over-drive, the protection circuits will kick in, and shut-down occurs. (hopefully just the fuses,, sometimes component thermal overload protection,,, or output-stage components such as capacitors). When those fail,,, you overload the drivers, and can burn the voice-coils in your speakers.

Now, getting back to your specific components,,, your JBL305s are powered monitors (85 w in "marketing-speak"). They're most likely 20w "continuous"/ 85w total peak. So far, those are the only components I;ve been able to find info on, aside from your power-amp. Please fill in the blanks. I need specific brand-names and model numbers of your 10" speakers,,, and the enclosures,,,, as well as your cross-over. Same goes for the 6" speakers.

Now, I'm no EE (electrical engineer),,, but I do know a few who might be able to help. I ran pro-sound rigs for a few years (Live sound applications for "Live" performance,,,, bands,,, musicians, etc. I have over 18,000 watts of pro-audio gear here,,, six mixers, analog and digital,,,, up to 24 channels each, and over 70 mic's for various "Live" or studio-sound applications. I have roughly 16 powered (active) speakers, and can handle crowds up to roughly 300 spectators,,, outdoors... with plenty of "thump". I also have three or four studio-rigs.
 

gregfisk

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Bruno is doing a lot of great things for class D but for me, and I own one of his amps I enjoy my Hafler more. Now one thing is for sure, class D amps are crystal clear and pretty much distortion free but for me they are just too clinical. I have a very clean set up with tubes in my dac. It has a volume control so I don’t have a preamp in the chain. I run a Mac mini as my source. The op is looking for a lot of power with a light budget which is why I suggested class D. You can’t beat the bang for buck but I don’t think they are the holy grail.
 
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