Monoprice Monolith 7-Channel Amplifier Review

Pogre

Pogre

Audioholic Warlord
Okay then, the Ascends in your system will still be the bottleneck as it is only rated 500 W maximum short term peak. You will need about 660 W to hit reference level with one speaker from 15 feet.

The Monolith can output only a little more than 500 W average short term dynamic peak, that's 1,000 W peak, two channel driven into 4 ohms.

Calculated results based on Ascend specs, for one single speaker:

Input data required:Input dataUnit
1) Speaker nominal impedance (Ohms)4.00Ohm
2) Sensitivity in dB/W at 1 MeterdB
3) Sensitivity in dB/2.83 V at 1 Meter90.00dB
4) Seating distance (1 foot = 0.3048 Meter, 1 Meter = 3.281 foot)4.57Meter
5) Room gain for speaker placement near walls/corners, enter 0 to 3 dB max., to err on the conservative side3.00dB
6) Desired additional amplifier headroom (dB) Recommended minimum is 3dB
7) Target SPL - THX reference is 85 dB, with 20 dB of headroom105.00dB
Calculated values from the input data:Calculated values
Sensitivity loss at seating distance (dB)13.20dB
SPL/W at seating distance calculated from the input data79.80dB
Amplifier power output based on 2.83 V and the assumed impedance at 1 Meter2.00Watt (W)
Power increase in multiples needed to achieve target SPL331.46
Power increase in dB needed to achieve target SPL25.20dB
Calculated amplifier output power required:
For the target SPL at seating distance663.66Watt (W)
For the target SPL at seating distance, with the desired headroom includedWatt (W)
Boom! Thanks Peng!

I am going to conclude that scooting a little closer will definitely take a little heat off my speakers at high volumes. The folks over at Ascend have been a little bit hit and miss to contact lately, with everything going on but they always eventually get back to me. I think I'm gonna shoot Dave an email and ask him ask about max spl at 1 meter, like you suggested I do with Ed for my Ultras.

You know what's interesting, tho maybe not overly surprising? My Monolith runs MUCH cooler powering my 4 ohm Sierra towers than it does my "8 ohm" Ultra towers. It's gets good and warm with the Ultras, but barely more than lukewarm with the Sierras. Even after some some very spirited listening sessions.
 
P

PENG

Audioholic Slumlord
Boom! Thanks Peng!

I am going to conclude that scooting a little closer will definitely take a little heat off my speakers at high volumes. The folks over at Ascend have been a little bit hit and miss to contact lately, with everything going on but they always eventually get back to me. I think I'm gonna shoot Dave an email and ask him ask about max spl at 1 meter, like you suggested I do with Ed for my Ultras.

You know what's interesting, tho maybe not overly surprising? My Monolith runs MUCH cooler powering my 4 ohm Sierra towers than it does my "8 ohm" Ultra towers. It's gets good and warm with the Ultras, but barely more than lukewarm with the Sierras. Even after some some very spirited listening sessions.
I just clarified my comments a little, but we were typing at the same time.:D

The Ascends are likely more sensitive and have better phase angles than the Ultras. I discussed power requirements with Ed before, you (may be not you but people who think amps are always needed for 4 ohm speakers) will be shocked if you know what he said..:D
 
operamatt

operamatt

Audiophyte
Those Monolith amplifiers are really well designed affordable amplifiers. You won't regret your purchase.

Are you an opera nut too? Because of my user name, it's not hard to guess who is my preferred Italian composer. If that is the case, maybe we could exchange comments at some point. In my collection, I have the complete Verdi Parma Opera series on Blu-ray, apart from all his operas on CD. That's only part of my opera collection.

I know quite a bit about opera singers and I am very critical about them. I studied classical singing. As a lyric tenor, I used to sing solos with choirs, and also sung in restaurants as a hobby. It was indeed a passion.

Cheers!
very cool, i also trained as a classical musician. my mane instrument was voice but i was a pianist & director as well. i’ve chosen a different path for my life but the love for classical music is still there.
 
RichB

RichB

Audioholic Field Marshall
Boom! Thanks Peng!

I am going to conclude that scooting a little closer will definitely take a little heat off my speakers at high volumes. The folks over at Ascend have been a little bit hit and miss to contact lately, with everything going on but they always eventually get back to me. I think I'm gonna shoot Dave an email and ask him ask about max spl at 1 meter, like you suggested I do with Ed for my Ultras.

You know what's interesting, tho maybe not overly surprising? My Monolith runs MUCH cooler powering my 4 ohm Sierra towers than it does my "8 ohm" Ultra towers. It's gets good and warm with the Ultras, but barely more than lukewarm with the Sierras. Even after some some very spirited listening sessions.
In general, when you consider stereo and room gain the volume at the listening position can be surprisingly close to rating at 1 meter (when accurately specified).
Ascends are among the best manufacturers at accurate sensitivity specifications.

Here is recent article on Audio Science Review:

Adding power to speakers that perform will with power (with good distortion characteristics) can lead to listening at higher levels. A small radio can seem too loud because the distortion is makes it unpleasant. That said, I have found I enjoy my Salons for casual listening at less than one watt. Of course, I'd like a near perfect 1'st watt ;)

THX specifications are for a single speaker but this is not representative of any realistic listening session.
To estimate my power usage I used the following procedure.

I played 250Hz, 1kHz, and 2kHz 0 DBFS (maximum volume) sine-wave tones and measured the voltage at the speaker adjusting the processor until it was as close as possible to 2.83 volts. The volume matches the speakers sensitivity rating. While playing the tone, I measured the SPL at my listening position of 11 feet.

The Salon2s are rates are 86 dB at 1 meter. The measured SPL was also 86 dB (with two speakers playing). The Salon2s are basically 4 ohm speakers that doubles to power. For my spreadsheet, this means -31 is 86 dB at 11 feet. From there I computed the attached power levels. Since I know my habits, the left column indicates those levels. Fortunately, the AHB2 amplifiers have accurate and clip meters per channel that illuminate for 1/4 seconds when the amp hits 1% distortion.
With music, they clip as expected with recording that peak at full scale (too many recording are maximized for volume).

Into 4 Ohms, the AHB2s deliver 180 WPC and they are not clipping at -10 so these numbers are conservative.
I also plugged in these numbers into the Crown power calculator: 3.5 meters, 101 dB, 83 dB sensitivity (for 4 ohms) and the required power is 773 watts.
My measurements and calculation show 64 watts stereo or 128 watts for a single speaker.

Measured SPL at Listening Position.jpg

CrownCalculatorSalon2.jpg


The Aquaman 4K BD has some formidable bass and I turned it up -15 (which is 3 dB louder than I found comfortable) and there is no clipping and the Salon2 3 8 inch woofers are really moving.

Unfortunately AVR amps are seldom measured as diligently as dedicated power amps and not going into protection is not a good indicator of distortion driving reactive loads. ;) Those measurements don't really exist. We know a lot about how amps play 1 kHz sine-waves into reactive loads.

- Rich
 
T

tparm

Audioholic
With Class D amplification being en vogue and ATI having success with their AT52XNC series, how long until there is a Class D Monolith variant? Thoughts? Insider info????
 

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