In the market for a new amplifier

[tgoyette]

So I learned my lesson the hard way about 'budget' electronics. I bought a Behringer EP1500 2 months ago... one of the channels crapped out on me the other day. It's still under warranty and I'll get a replacement. Thing is, I don't really want another one as I had a few issues with the unit before it actually malfunctioned.

So.. now I have an excuse to buy a new amp! I'm interested in stereo for music use 90% of the time with an occasional movie thrown in. My current pre/pro is an Emo Rsp1, and the amp will be soon powering a set of Rocket 850s from Av123.

I'm looking to keep the budget at or below 700. Any suggestions? Currently favoring the outlaw monoblocks which look nice, plus free shipping for a pair at 625. The xpa 2 from emotiva also looks very nice, but its a little beyond my budget at the moment.

Tim

 

[EJ1]

What is the recommended power range for those? I can't seem to find it anywhere.

 

[tgoyette]

I can't remember; I'm looking now and can't seem to find it either.

 

[mike c]

im going bonkers for the amps at www.d-sonic.net
if only i could afford them ... unlimited power (practically) for less than Rotel prices.

maybe you can upgrade/trade-in your amp for the EP2500 ... the 2500 has always been the better unit.

 

[bandphan]

im going bonkers for the amps at www.d-sonic.net
if only i could afford them ... unlimited power (practically) for less than Rotel prices.

maybe you can upgrade/trade-in your amp for the EP2500 ... the 2500 has always been the better unit.

ice ice baby

 

[cfrizz]

Either one of those amps will do the job. Go for it.

 

[Seth=L]

WmAx doesn't ever recommend the EP1500 (I typically trust his opinion), it's always the EP2500 (which is quite a bit different from the EP1500) as it has more power, it's construction is unrivaled at the price, and it's not much more than the EP2500.

Time to trade up?

 

[jamie2112]

There alot on audiogon right now.

 

[tgoyette]

My main issues with the EP1500 are the fan noise and the cheap binding posts for the speakers and balanced connectors. It's hard to tell from pics of the 2500 if the connectors are of a higher quality.

 

[Seth=L]

The stock fan can be replaced with a quieter fan.

 

[tgoyette]

How expensive/technical is replacing the fan if I were to do that? Would it be inaudible after the replacement? I like to do as much quiet listening as I do loud so a silent operation is a must. Thanks

 

[furrycute]

Do you have a cabinet where you can stick that amp in? Over the years I've found that's the best way to deal with fan noise.

Or if your listening room is large, run some long speaker cables, 50ft per speaker should be plenty long (use 12 gauge cables in this instance). This way, the amp is away from your listening position, the fan noise becomes hardly noticeable.

 

[brulaha]

I'm thinking of parting with a Proceed HPA 2 if you're interested.

It's a class "A" amp dual monoral construction rated at 250 WPC. It runs dead silent due to the way it's heat sinks are designed.

Let me know if you're interested.

 

[tgoyette]

No cabinet to speak of. In fact, my listening room is small, and I listen nearfield. I like a very intimate and detailed sound for music. I really didn't think the fan noise would bother me much when I bought the Behringer, but it was overpowering during quiet listening sessions.

 

[furrycute]

Then I don't think any fan cooling based amplifier will work for you. Some kind of fan noise will always be noticeable during quiet passages no matter how quiet that fan is.

What kind of speakers are you running? If they are 8 ohms, you may want to take a look at a Harman stereo receiver. There is a model that outputs 120wx2 channels. I don't remember the model number. But just do a search, that's quite a nice stereo receiver. I think it costs something like $250.

 

[Midcow2]

you want a sound level of at least 108 dB ...

to get the true HT effect.

For SPL (Sound Pressure Level) the forumal is 20dB = 10x power

The Rocket 850s have an effciency of 91.5 db at 1 watt at 1 meter.


A 75 watt amp will provide a gain of 18.8dB for a total of 110.3 dB less dispersion lossed

A 100 watt amp will provide a gain of 20 dB for a total of 111.5 dB less dispersion lossed

A 150 watt amp will provide a gain of 21.8 dB for a total of 113.3 dB less dispersion lossed

A 300 watt amp will provide a gain of 24.8dB for a total of 116.3 dB less dispersion lossed

Typical dispersion loss is 7.7dB so you would probably want a 150 RMS per channel amp to suffciently drive the Rocker 850s at a fairly loud HT level. You could get by with less, but you might not be fully satisfied. If you could audition the Rocket 850s with different receivers you could see the difference.

=========================

There is a SPL calculator at : http://myhometheater.homestead.com/splcalculator.html

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[tgoyette]

I listened to the 850s through my stereo rig (prior to the Behr malfunctioning) as well as in a 5.1 setup which I believe was powered by a parasound, but the model escapes me. There was little audible difference to my ears, the only difference being the 2 channel sounded a little more 'focused.' We weren't going anywhere near the full volume potential of either setup though. Lesson is, more power is always better right?

 

[PENG]

to get the true HT effect.

For SPL (Sound Pressure Level) the forumal is 20dB = 10x power

The Rocket 850s have an effciency of 91.5 db at 1 watt at 1 meter.

================================

Just for clarity, you are talking about sensitivity, not efficiency.

 

[WmAx]

What do you mean cheap binding posts? While I have never used the EP1500, I have a few A500s and an EP2500 on hand, and they both have standard binding posts suitable for 12 AWG wire or banana connectors. I believe both the EP1500 and EP2500 also have Neutrik-style pro-audio connector that can accept the Nuetrik-style plug or standard 1/4" TRS plugs.The EP1500 uses the same basic design as the EP2500; but it lacks the 2nd high power rail of the EP2500 and has a smaller PS, which results in substantially lower output power. Since you can get both for the same price($300 vs. $350 - and if you look around, the EP2500 can be had for 270-300), it makes no sense to go with an amp without almost half the power(the EP1500).

The fan is changed out with an $8 silent replacement unit - It takes about 20 minutes from start to finish. If you want the model number just let me know.

-Chris

 

[WmAx]

I think you meant to say 100x power is required to get 20dB amplitude increase. You seem to have made a typo in your 2nd line.

Additionally, while the formula may work out to a specific SPL; the formula does not account for actual driver limitations and thermal compression that will make the actual results fall short of the calculated ones.

-Chris

to get the true HT effect.

For SPL (Sound Pressure Level) the forumal is 20dB = 10x power

The Rocket 850s have an effciency of 91.5 db at 1 watt at 1 meter.


A 75 watt amp will provide a gain of 18.8dB for a total of 110.3 dB less dispersion lossed

A 100 watt amp will provide a gain of 20 dB for a total of 111.5 dB less dispersion lossed

A 150 watt amp will provide a gain of 21.8 dB for a total of 113.3 dB less dispersion lossed

A 300 watt amp will provide a gain of 24.8dB for a total of 116.3 dB less dispersion lossed

Typical dispersion loss is 7.7dB so you would probably want a 150 RMS per channel amp to suffciently drive the Rocker 850s at a fairly loud HT level. You could get by with less, but you might not be fully satisfied. If you could audition the Rocket 850s with different receivers you could see the difference.

=========================

There is a SPL calculator at : http://myhometheater.homestead.com/splcalculator.html

================================