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returning to passive monitors, need a power amp recommendation

tuj

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Hi all:

First time posting here but I have been reading the reviews/measurements for a while now. I have recently returned to passive monitors in my studio. These are Dynaudio BM15's which are 4ohm and not very sensitive (88dB) so they want to see a min of 50w per channel. I got rid of my power amps a while back and I have no idea what in the recent past (e.g. used) or current market are good choices for my situation. I would greatly prefer not to have a fan. The BM15's are banana jack so that should be standard. I can handle whatever input is needed (e.g. RCA, 1/4, XLR) but would prefer a balanced solution like 1/4 TRS or XLR. That said, my cable run to the amp will be sub-10'.

I don't need specifically a rack / studio amp; a receiver would be ok too, but I don't really need any of the extras a receiver brings. I do not work at even what I would call 'high' volume levels. My current room is fairly small and the speakers are within just over a 1m of my sitting position. Spec says "min amp: 50 W (> 94 dB SPL @ 2m)". I am familiar with the logarithmic nature of the dB scale and thus the associated power requirements. I also don't want to run my amp at 100% of it's rating or even really more than say 50%. As a studio amp, it will be on for long periods of time and sometimes the ambient temperature can exceed 79F for short periods before the HVAC cooling catches up, if all the studio gear is on say. Normally ambient is 71-75F.

I also am aware that some lower-end amps exhibit self-noise > -100dB and thus could possibly hiss. I certainly want to avoid that although I imagine the low sensitivity may actually help that?

I in the US, willing to buy new or used. I would prefer to spend ~$500 or less. I am not asking for audiophile quality but dependable operation, relatively flat response within the audio range, and adequate power to push these monitors. I'm well aware this combination of requirements may be non-existent, so of course I am open to hearing options of compromise.

Thanks for your potential advice!
 

Chrispy

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Minimum wattage tends to crack me up a bit....as most aren't using but a few watts especially at your distance from the speakers and they appear relatively sensitive. Do you need more than 50W listening that close? Or will this power amp have other uses (in terms of speakers/rooms/levels) down the line and you just want sufficient amp for whatever you end up doing?
 

Curvature

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Minimum wattage tends to crack me up a bit....as most aren't using but a few watts especially at your distance from the speakers and they appear relatively sensitive. Do you need more than 50W listening that close? Or will this power amp have other uses (in terms of speakers/rooms/levels) down the line and you just want sufficient amp for whatever you end up doing?
Instantaneous wattage requirements are much, much higher than average, which as you say is low.

This is a nearly full range speaker so you can expect the bass to require more average power as well.

The OP is asking according to Dynaudio guidelines, by the way.
 

Chrispy

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Instantaneous wattage requirements are much, much higher than average, which as you say is low.

This is a nearly full range speaker so you can expect the bass to require more average power as well.

The OP is asking according to Dynaudio guidelines, by the way.
Yeah, I get all that, was more indicating we just need more info about specific use (or future uses); he says he doesn't need particularly high levels and is at only 1m distance from the speakers. Personally I wouldn't bother buying an amp with only 50wpc as being of quite limited use in general, let alone for my general purposes....just wonder about his.
 

BDWoody

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Maybe an older Adcom? I just hooked my 545 II up to run passive subs and am happy I never sold it.
 

Plcamp

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Maybe an older Adcom? I just hooked my 545 II up to run passive subs and am happy I never sold it.
I agree, I can get old Adcom 535II amps (rated 80W) used in Canada for <$200, they sound great and run cool and are 1/3 the size of most power amps.
 

amper42

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Hi all:

First time posting here but I have been reading the reviews/measurements for a while now. I have recently returned to passive monitors in my studio. These are Dynaudio BM15's which are 4ohm and not very sensitive (88dB) so they want to see a min of 50w per channel. I got rid of my power amps a while back and I have no idea what in the recent past (e.g. used) or current market are good choices for my situation. I would greatly prefer not to have a fan. The BM15's are banana jack so that should be standard. I can handle whatever input is needed (e.g. RCA, 1/4, XLR) but would prefer a balanced solution like 1/4 TRS or XLR. That said, my cable run to the amp will be sub-10'.

I don't need specifically a rack / studio amp; a receiver would be ok too, but I don't really need any of the extras a receiver brings. I do not work at even what I would call 'high' volume levels. My current room is fairly small and the speakers are within just over a 1m of my sitting position. Spec says "min amp: 50 W (> 94 dB SPL @ 2m)". I am familiar with the logarithmic nature of the dB scale and thus the associated power requirements. I also don't want to run my amp at 100% of it's rating or even really more than say 50%. As a studio amp, it will be on for long periods of time and sometimes the ambient temperature can exceed 79F for short periods before the HVAC cooling catches up, if all the studio gear is on say. Normally ambient is 71-75F.

I also am aware that some lower-end amps exhibit self-noise > -100dB and thus could possibly hiss. I certainly want to avoid that although I imagine the low sensitivity may actually help that?

I in the US, willing to buy new or used. I would prefer to spend ~$500 or less. I am not asking for audiophile quality but dependable operation, relatively flat response within the audio range, and adequate power to push these monitors. I'm well aware this combination of requirements may be non-existent, so of course I am open to hearing options of compromise.

Thanks for your potential advice!

I would suggest the Buckeye NC252MP amp with 250W @4 ohms or 150W @8 ohms for $579.

It offers a fantastic sound at a very reasonable price. I'm not aware of a better value per dollar. If you want even more power look at the Buckeye NC502MP with 500W @4 ohms or 350W @8 ohms for $749.

I have four NC502MP stereo amps and no matter what system I put them on they sound absolutely wonderful. As far as I am concerned the Buckeye amps are a great find in the crowded arena of audio amplifiers.
 

jamescarter1982

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Speakers in question: https://www.dynaudio.com/professional-audio-discontinued/bm-legacy/bm15

Direct answer to your question: https://www.audiophonics.fr/en/powe...wer-amplifier-ncore-2x125w-4-ohm-p-12756.html

Probably unwanted answer: Sell your speakers and spend the proceeds and the extra $500 on actives from Neumann or Genelec.
Hi all:

First time posting here but I have been reading the reviews/measurements for a while now. I have recently returned to passive monitors in my studio. These are Dynaudio BM15's which are 4ohm and not very sensitive (88dB) so they want to see a min of 50w per channel. I got rid of my power amps a while back and I have no idea what in the recent past (e.g. used) or current market are good choices for my situation. I would greatly prefer not to have a fan. The BM15's are banana jack so that should be standard. I can handle whatever input is needed (e.g. RCA, 1/4, XLR) but would prefer a balanced solution like 1/4 TRS or XLR. That said, my cable run to the amp will be sub-10'.

I don't need specifically a rack / studio amp; a receiver would be ok too, but I don't really need any of the extras a receiver brings. I do not work at even what I would call 'high' volume levels. My current room is fairly small and the speakers are within just over a 1m of my sitting position. Spec says "min amp: 50 W (> 94 dB SPL @ 2m)". I am familiar with the logarithmic nature of the dB scale and thus the associated power requirements. I also don't want to run my amp at 100% of it's rating or even really more than say 50%. As a studio amp, it will be on for long periods of time and sometimes the ambient temperature can exceed 79F for short periods before the HVAC cooling catches up, if all the studio gear is on say. Normally ambient is 71-75F.

I also am aware that some lower-end amps exhibit self-noise > -100dB and thus could possibly hiss. I certainly want to avoid that although I imagine the low sensitivity may actually help that?

I in the US, willing to buy new or used. I would prefer to spend ~$500 or less. I am not asking for audiophile quality but dependable operation, relatively flat response within the audio range, and adequate power to push these monitors. I'm well aware this combination of requirements may be non-existent, so of course I am open to hearing options of compromise.

Thanks for your potential advice!
I use the mc2 mc650 with dynaudio bm15 passive . its a great sounding combination . the monitors are very power hungry and the yamaha reciever I also tried sounded strained I believe the yamaha wasn't able to cope with the low impedance or provide enough power . would recommend mc2 amps wholeheartedly the t1000 is available used for around £300 and provides even more power than my model
 

Phorize

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I would suggest the Buckeye NC252MP amp with 250W @4 ohms or 150W @8 ohms for $579.

It offers a fantastic sound at a very reasonable price. I'm not aware of a better value per dollar. If you want even more power look at the Buckeye NC502MP with 500W @4 ohms or 350W @8 ohms for $749.

I have four NC502MP stereo amps and no matter what system I put them on they sound absolutely wonderful. As far as I am concerned the Buckeye amps are a great find in the crowded arena of audio amplifiers.
Was about to make the same recommendation. The 252 is $579 including shipping.
 

Phorize

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Or this:


Would want to know when the fan kicks in, I'd suspect not at all in your use case.

Edit: forget this amplifier, the measurements show be powerful but a mass of distortion and noise.
 
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audio2920

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I've previously run BM15s on Crown DSi and Hypex 502MP; all day long I'd choose the Hypex.
 
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