The 641 is an integrated amplifier by MOON that delivers 125 watts x 2 channels into 8 ohms and 250 watts x 2 channels into 4 ohms. It was released in 2023. It is a 2-channel design using a Class A/B output stage. Speakers connect via binding posts. A minimum impedance of 4 ohms makes it compatible with a wide range of loudspeakers. The MOON 641 has an MSRP of $11,000.
There are 2 MOON amplifiers in our database. Below you can see the main specs of these amps.
MOON Integrated Amplifier Series
Performance Specs
One of the most important factors when deciding on an integrated amplifier is its power ratings and compatibility with your speaker's impedance requirements. The MOON 641 is rated at 125 watts RMS into 8-ohms. MOON provides this wattage at a THD (Total Harmonic Distortion) of 0.003% which is an important indicator of distortion at the given values (lower THD is better).
Here are the main highlights of its performance specs:
- 125 watts into 8-ohms (2 Hz-90 kHz) at 0.003%
- 250 watts into 4-ohms
- 4-ohms Min Impedance (allows compatibility with a wide range of loudspeakers)
- 109dB Signal to Noise Ratio
How loud will 125 watts actually play in your room? →
Wiring more than one pair of speakers to it? Check the load first →
Which speakers suit the MOON 641?
125 W into 8 ohms, 250 W into 4, rated down to 4 ohms.
We rank every passive speaker we cover against it on power, impedance safety and current
delivery.
Need more power?
MOON 641 is rated at 125 watts into 8 ohms, which puts it in our 121 to 180 watts band. The next band up is Over 180 watts, which is worth about 2.3dB more output. That is a real difference in headroom on peaks, and a modest one in how loud the system plays - power and loudness are not the same thing.
Before buying watts, check what your speakers actually need: the amp and speaker matcher works it out from their sensitivity, impedance and your room. Plenty of systems are better served by the 91 to 120 watts band and better speakers.
When pairing the MOON 641 with a passive Bookshelf (Stand mount) or Passive Floor Standing (Tower) speaker, you have to check if their Max Power Range is below the max wattage of the amp for the given impedance levels.
Operating your amp outside of this max range may damage the speakers.
What size of room is the MOON 641 Amplifier good for?
An essential deciding factor is the size of the room in which you intend to employ the MOON 641 amplifier. Here, taking into account its maximum power parameters, we analyzed its applicability to various size environments:
| Listening Environment |
Suitability |
| Near-field | Poor |
| Small Room | Poor |
| Mid-size Room | Good |
| Large Room | Good |
| Very Large Room | Average |
Inputs and Outputs
Besides the performance specs of the MOON 641, the next important feature set that you have to evaluate is the input and output selections that it offers.
MOON 641 has total of 5 Analog inputs .
Inputs
- Total Number of Analog Inputs: 5
Outputs
Bluetooth Connectivity
MOON 641 doesn't have bluetooth connectivity feature. In order to stream your music via bluetooth, the easiest way is to connect an external bluetooth receiver to your MOON 641. Two bluetooth receivers that we recommend are the
iFi Zen Blue V2 and the
Audioengine B1.
Among the amps in the same price range, these are the 2 amps that have Bluetooth Connectivity:
Balanced connections
MOON 641 has a balanced XLR input. A balanced cable carries the signal twice, on two conductors of opposite polarity. Interference picked up along the way lands on both equally and cancels when the two are recombined at the far end, so the longer the cable run and the noisier the surroundings, the more the connection is worth. Whether a balanced connection also yields more power depends on how the amplifier is built inside - some are balanced end to end, others convert to single-ended internally and deliver the same power either way, so it is worth reading the maker's own wording rather than assuming.
MOON 641 Pros and Cons
Drawn from the published figures on this page, not from listening.
- ✓Power nearly doubles into a harder load, 125 watts into 8 ohms rising to 250 into 4, which points to a power supply with real current in reserve.
- ✓Damping factor of 700 means a low output impedance and firm control over a woofer.
- ✓Signal-to-noise ratio of 109dB, so the amplifier itself should be inaudible between tracks.
- ✓Distortion is specified at 0.003%, an order of magnitude below what is generally held to be audible.
- ✓5 analogue inputs, enough for a full rack of sources.
- ✓Balanced XLR inputs, worth having on a long cable run.
- ✗Analogue inputs only - a TV, computer or CD transport needs an external DAC.
- ✗No Bluetooth and no network streaming - everything arrives over a cable.
- ✗It weighs 26.1kg - check the shelf, and plan on a second pair of hands.
MOON 641 External Dimensions and Weight
MOON 641 has external dimensions of (H x W x D) 4-1/16 x 18-15/16 x 18-5/16 inch (102.4 x 481.3 x 465.3 mm ). The unit weighs
26.08 kg (57.5 lbs).
Base Surface Area
Base surface area of an integrated amplifier may become an important decision factor when the space in your room or desk is limited.
The base area of the MOON 641 is approximately 2239.5cm2 / 347.1inch2.
- Width: 481.3mm (18-15/16")
- Height: 102.4mm (4-1/16")
- Depth: 465.3mm (18-5/16")
- Weight: 26.08 kg (57.5 lbs)
- Base Surface Area: ~2239.5cm2 / 347.1inch2
- Volume: ~22.9 liter / 6.1 gallon
Available colors
MOON 641 is available in Black and Silver color options.
| General |
| Brand |
MOON |
| Full Model Name |
MOON 641 |
| Release Date |
2023 |
| Amplifier Type |
Integrated Amplifier |
| Number of Channels |
2 |
| Amp Class |
Class A/B |
| Amplifier Technology |
Solid State |
| Performance |
| Watts RMS per Channel into 8-ohms |
125 watts |
| Watts RMS per Channel into 6-ohms |
N/A |
| Watts RMS per Channel into 4-ohms |
250 watts |
| Frequency Bandwidth |
2 Hz-90 kHz |
| Damping Factor |
700 |
| THD |
0.003% |
| Minimum Impedance |
4 |
| Signal to Noise Ratio |
109 dB |
| Digital Music |
| Built-in DAC |
No |
| Bluetooth |
No |
| WiFi |
No |
| CONNECTIONS |
| Total Analog Inputs |
5 |
| Headphone Output |
No |
| Removable Power Cord |
|
| Speaker Connectors |
Binding posts |
| PHYSICAL SPECS |
| Height |
102.4mm (4-1/16") |
| Width |
481.3mm (18-15/16") |
| Depth |
465.3mm (18-5/16") |
| Weight |
26.08 kg (57.5 lbs) |
| Available Colors |
Black,Silver |
| OTHER |
| Parts Warranty |
|
| Labor Warranty |
|
How much power does the MOON 641 have?
The MOON 641 delivers 125 watts x 2 channels into 8 ohms and 250 watts x 2 channels into 4 ohms. Its output almost doubles into 4 ohms, which points to a strong power supply that can hold its composure with demanding, low-impedance speakers.
Does the MOON 641 use vacuum tubes?
No. The MOON 641 is a solid-state amplifier - there are no vacuum tubes in it.
What amplifier class is the MOON 641?
The MOON 641 uses a Class A/B amplifier design. Class A/B is the traditional linear design: it runs warmer and is less efficient than Class D, but it is long valued for its natural, low-distortion sound.
Does the MOON 641 have a built-in DAC?
No. The MOON 641 has no built-in DAC, so a digital source such as a streamer or CD transport needs its own converter, or you connect it over analogue.
Does the MOON 641 have Bluetooth?
No. The MOON 641 does not have Bluetooth built in; you would need an external Bluetooth receiver connected to one of its inputs.
Does the MOON 641 have a headphone output?
No. The MOON 641 does not have a headphone output, so headphone listening needs a separate headphone amplifier.
How much does the MOON 641 cost?
The MOON 641 has a manufacturer's list price (MSRP) of $11,000.
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