Sound+Sleep SE Sound Machine Review: No Loops Please

Sound+Sleep SE Review

I have now used the Sound+Sleep SE for a couple of months and want to share my review.

Most nature sound machines work like a simple MP3 player on repeat.

You choose a sound like “ocean surf,” the machine plays a recorded sound, and having reached the end, it starts over and repeats the recording.

If good care has been taken so that you don’t hear a break when it restarts, this can work quite well.

Unfortunately, in most current machines the recordings are rather short, so our brain learns quickly that after a certain wave crashes into the shore, the sound is going to restart.

ASTI advertises the Sound+Sleep SE as a sound machine with naturally recorded sounds that constantly evolve and never loop.

You might have heard that “doesn’t loop claim” from many manufacturers, only to find that you were able to detect loops and patterns in the sounds.

So does the Sound+Sleep perform as advertised?

I have now listened to the SE for many hours and as far as I can hear, the manufacturer’s description of this sound machine is accurate.

I wasn’t able to detect loops and the sounds really are evolving. These are very well designed sound stories.

Throughout this review, I have woven in samples of my favorite sounds, so you can decide whether you share my taste.


For nature sounds, the Sound+Sleep SE is the best standalone sound machine I have so far had the pleasure to listen to.


  • For practical purposes the machine really is non-looping.
  • Very large selection of rich nature sounds, in particular sounds related to water.
  • Well thought-out and easy operation (even in the dark), considering that the machine has 64 different sounds.
  • All lights can be turned off.
  • Appears to be a multi-track sound machine (rather than a one-track sound player on repeat) that dynamically mixes different recorded sounds.
  • White noises and fan sounds are dynamically created (using a synthesizer).


  • Not ideal for travel: the machine is quite large and only supports AC power (but voltages from 100 to 240 V).
  • I would like a few more serene sounds, like a meadow with only wind (without any crickets and water), or only birds (without any water).
  • Pink and white noise selections should sound more accurate when played through the speaker: they have a boosted bass, but the mid-frequencies are attenuated, giving me the feeling that something is missing. Via the headphone jack, the white noises sound fine (and so is the frequency spectrum), so I think it is the speaker’s tuning or the equalization. The white noise generator itself is good.
  • A machine of this caliber should have a user-accessible equalizer.



The Sleep+Sound SE has a total of 64 sounds, also called sound stories:

  1. Rotate the dial to select between one of 16 sound categories.
  2. Then use the selection button to choose one of 4 sounds within a given category and adjust the volume to your liking. (The machine memorizes your favorite in each category.)

Often the sounds in a given category (in particular the water sounds) are similar and mainly differ in their “richness.”

For example, within the category rainfall, you can choose between the following:

  • rain,
  • rain with wind and light thunder,
  • rain with heavy wind and thunder,
  • and rain with heavy wind and heavy thunder.

Here is a sample of the rain with heavy wind and thunder (first the recorded speaker output, then directly via the headphone jack).

I’ll weave in more sound samples throughout this review, so you get an idea whether this is something for you.

Rain via the speaker:

Rain via the headphone jack:


Why two samples?

  • I think the speaker is fine for nature sounds, and I wanted to give you an idea of how it sounds.
  • But via headphones you get to enjoy the complete frequency spectrum of the sounds, so I’ll provide samples for this as well.

The category “baby” is an example where different sounds are grouped together. In this category we have:

  • undersea whales,
  • whale party,
  • heartbeat,
  • aviary.

Before trying, I didn’t think much of that category, but now both whale sounds (they come with calming ocean sounds) and the aviary—different types of birds amidst flowing water—are among my favorites .

The whale sounds are addictive.

Here is a sample of the whale party (recorded speaker output):

And here is a sample of the whale party directly via the headphone jack:


The machine remembers the last chosen sound in each category, so you can later just dial through your 16 favorites.

With this machine, they have gotten the operation right.  It works great for me, even in the dark.

The Sound+Sleep also has an Adaptive Sound feature

In this mode, the machine uses a built-in microphone to assess the environmental noise level and automatically increases / decreases the volume (and even adds sounds) if the room has become louder / quieter.

I have tried this feature and it is quite responsive, but so far I haven’t found an application for it.

For the time being, I prefer to set the volume according to my preference and then listen to the sound while I fall asleep or focus on my work.

Other notable features

Auto-light off via the display button: Every function has an LED that signals whether the user has activated it. With auto-light off enabled, all LEDs are being turned off a few seconds after your last activity. Pressing any button turns the LEDs back on, again for a couple of seconds.

Timer: Choose between 30, 60, 90, and 120 minutes after which the sound slowly fades out.

Nature sounds and sound quality

I have found the sound stories on the SE to be very well designed. I don’t hear any breaks, there is a lot of variation in individual sounds, and I also don’t hear obvious repetitions.

The speaker is fine for listening to nature sounds and the machine reveals the complete frequency spectrum when using the headphone jack.

It appears to me that the SE dynamically mixes different recordings (tracks) to create these sound stories.

With a standard sound machine that uses short recordings, if you play an ocean surf sound that features a seagull, the waves always crash into the shore at the same time, and the bird always appears at the same position and always sounds the same.

So after a while it gets repetitive even if you don’t hear a break when the sound restarts.

This machine is different. Every time you play it, the ocean sound starts slightly different and the seagull, seagulls, or seals appear at different times so you can’t predict them.

The machine has 64 sound stories, and I won’t bore you critiquing them all.

Here is a very incomplete sample selection of sounds I like.

We have already listened to rain and the whale party. If you have missed those scroll up to the section Operation.


The SE has four ocean sounds. I like all of them but #1 and #2 are my favorites.

This is ocean sound #1 (waves and lapping water) (speaker output):

And here is another sample of the same sound via the headphone jack:


Again, there are four sounds in this category.

The is a sample of meadow #1 (crickets, wind, bird wings & splashing water):

And here is a different sample of meadow #1, played via the headphone jack:


This category contains a plane ride, a car ride, a train ride, and a paddle boat ride.


Here is a sample of the train ride (speaker output):

And here is another sample (using the headphone jack):


Plane (speaker output):

Plane (via headphone jack):


(the bird’s house from the category Baby):

and here are the birds via the headphone jack:


The fireplace from the category Home is an excellent sound.

Other sounds in this category include Bath, Air Conditioner, and Washer.

Fireplace (recorded via the speaker output):

Fireplace (via the headphone jack):

White Noises and fan sounds

The Sound+Sleep SE has 12 white noises, categorized as brown noises (4), pink noises (4), and white noises (4).

These sounds are dynamically created using a multi-voice synthesizer, so they are non-repeating which is great.

When I listen to them via headphones, they sound just like they should. So the sound generator is good.

However, when listening to them via the speaker, they have a boosted bass and attenuated mid frequencies.

They sound alright, but compared to the way they sound with headphones to me something is missing.

With the brown noises this is not so much of a problem, but the pink noises and white noises don’t sound smooth enough for my taste.

To adjust these and other sounds, I would appreciate if the SE came with a user-accessible equalizer.

I have compared the white noises to the ones on one of my favorite white noise machines, the Lectrofan Classic (which also uses a synthesizer), and I prefer the ones on the Lectrofan Classic.

Note: There are no nature sounds on the Lectrofan.


Sound+Sleep-SE vs Lectrofan White Noises

But perhaps your taste is different?

I have recorded speaker output samples of the four brown noises and the first two pink noises.

Take a listen (first six white noises):

For comparison, here are samples of the first six white noises produced by the Lectrofan Classic:

Fan sounds

Like the white noises, the fan sounds are created dynamically using a synthesizer. I much prefer this over recordings, which is what is used in most machines.

The SE has 4 small and 4 large fan sounds.

My favorite fan sound on the Sound+Sleep SE is small fan #4.

Here are samples of the four small fans (speaker output):


And here are samples of the four large fans (speaker output):


The fans on this machine sound similar to the ones on the Lectrofan Classic and Lectrofan EVO, but the SE fans have more bass.

Generally, I prefer the somewhat lighter fans of the two Lectrofans, but perhaps you like more bass.

Also, the additional bass on the Sound+Sleep can be helpful to mask lower-frequency noises.

Power, ports, and headphones


The SE comes with a multi-voltage power adapter (100 – 240 v), so it should work in most countries around the world. The plug that goes into the machine is of the round-type, so you can’t easily use other power sources.

Unless you start tinkering yourself, the machine needs to be plugged into AC-power.

The SE also has a standard 3.5 mm headphone jack, which I have used extensively.

I have tried several different headphones, including Sony studio headphones (MDR-7506), CozyPhones sleep headphones, Bose QC 35, and a pair of Panasonic on-ears.


While these headphones all sound different, I like the sound of the SE with all of them.

I suggest you listen to the headphone sound samples above (section nature sounds) with your headphones to get a feel for the sound.

I should point out that there is no stereo effect such as waves moving from the left to the right ear, but I actually don’t mind that. You hear exactly the same on both channels when using the headphone jack.

Sometimes it is nice to have stereo. The manufacturer should consider this in a future version.

One the other hand, I would want to be able to turn stereo effects off:  for me, excessive effects can be disturbing when trying to fall asleep or focus.

Input jack

I have also tried the input jack of the SE with my phone. It is OK for occasional listening, but the speaker doesn’t really get loud enough with the phone as a source. (It does get loud when playing the machine’s sounds.)

I would like to see a future version equipped with Bluetooth

Many people use wireless headphones these days. I would like to see this sound machine be equipped with both a Bluetooth transmitter (so that I can listen with Bluetooth headphones) and a Bluetooth receiver (so that I can use the speaker and stream music from my phone or iPad).

As a workaround if you want to use Bluetooth headphones, you can plug a Bluetooth transmitter into the headphone port. I have tried that and it works fine.  It means you have to add an extra gadget that needs to be handled and charged, but there is a way.

USB ports

I have used the USB ports to charge my phone and also connected a little LED lamp (as a night light).  The ports supply 0.9A of power each. Unfortunately, this is not enough for charging my iPad.


Nature sounds

For nature sound, the Sound+Sleep SE is by far the best standalone sound machine I have had the pleasure listening to.

There are many high-quality sounds to choose from and many different elements to discover in each of them. I am not aware of any other machine that offers something comparable.

Also, the machine is easy to operate and works well together with headphones, including sleep headphones.

Recommended use case

The SE is a good choice if you want a stationary nature sound machine to relax and fall asleep. It has a particularly rich selection of water-related sounds.

It should also do well in an office or home office to mask noise and help with focus.

The SE is too large as a travel machine. Also, it is strictly AC-powered.

The true value of this machine lies in its very nicely designed sound stories and well-thought out operation.  

This really is a sound machine, not a one-dimensional memory-strapped MP3 player like many pretenders.

White noises

The SE has a good white noise generator, offering 12 different pitched clean white noises that don’t repeat. and 8 fan sounds.

However, when played via the speaker, for my taste, the white noises have a bit too much bass and lack somewhat in the soothing mid frequencies.

The white noises sound fine when played via headphones; I think the speaker output is more tuned for nature sounds.

If you are looking for an only-white-noise machine or fan sounds (as opposed to nature sounds), the Lectrofan Classic is a better, cheaper, and more portable choice.

On that machine, the white noise selections are well-equalized for the speaker.

Alternatively, for fan sounds the Lectrofan EVO is also a great choice.

I have done an in-depth review comparing the Lectrodan Classic and the EVO, if you’d like to learn more about them.

If I could only suggest a single change:

I would like to see ASTI (the manufacturer) allow the user to change the pitch of the sounds.

ASTI states that the SE has a 5-band parametric equalizer. But, this equalizer is not user-accessible.

Give us this 5-band equalizer, perhaps on the side where the USB ports are now.

This is not a deal breaker; for nature sounds the machine sounds good the way it is, but it would make it even better.

(To keep the operation as simple as it is now, separate bass, mid, and treble knobs to adjust the sounds to our liking could work too. These knobs would have a clear tactile zero position.)

The settings should apply to both the speaker and the headphone jack.

For most white noise applications, I would turn down the bass and up the mid frequencies and be content. But sometimes, I would boost the bass and turn down the treble to mask some nasty environmental noises.

Also, people with less than stellar hearing could greatly benefit: they could emphasize the frequencies they are missing.

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