A popular opinion in the brainwave entrainment community is that listening to isochronic tones without music produces a much stronger effect.  However, in the study by Doherty, Cormac. “A comparison of alpha brainwave entrainment, with and without musical accompaniment” (2014),  it was concluded that brainwave entrainment was equally effective for isochronic tones, both with and without music.
When I am using equisync I feel kind of like it is “pushing me” – I guess this is the right way to say it- to achieve better results, which I really like. I fall asleep quickly, and sleep all night and even wake up before my alarm goes off. I feel noticeably calm during the workday- which is very helpful for what I do. I really like the warm feeling (my whole body gets really warm during my equisync meditation sessions) and I feel kind of like Im floating while listening. The soothing rainfall is also very nice.

We all experience different states of mind each day: states such as sleep, focus, or creativity, for example. Every state of mind has a unique electrical signature that can be detected in the brain. These signatures are known as “brainwaves.” Using specialized equipment, these waves (or frequencies) can be measured and recorded, allowing us to map what brainwaves are present during certain key states of mind.
I have been using the Equisync CDs at least 24 minutes 5 days a week. It instantly relaxes me, helps get rid of headaches and even hiccups! I have a stressful job and it helps prevent anxiety; I have not had a chance to check my blood pressure but I feel calmer. I have used other products before but I like the Equisync CDs much better; it is deeper and more relaxing.
Most wisdom traditions have employed methods that allow the subjects' brain waves to slow down such as meditation, [Hindu] kirtan, [Gregorian, Menzuma or Sufi] chanting, Hebrew davening, Native American drum circles and rain chants, Tibetan prayer bowls, and whirling dervishes and African trance dancing. The rhythm of these wisdom tradition technologies actually slows people's brain waves from their normal busy brain frequency we call Beta (13-30 cycles per second or Hz), to Alpha (8-13Hz) -- meditation, Theta (4-8Hz) -- deep relaxation and dreaming, and Delta (.5-4Hz) -- slow wave or dreamless sleep.

Theta stimulation: There appears to be no benefit associated with using theta stimulation for cognitive functioning, mood, or stress relief. While theta may be a useful way to induce sleep or alter your state of consciousness, there really isn’t much science supporting entrainment in this particular range for most purposes. Photic stimulation of theta between 5 Hz and 7 Hz can be useful for headaches.
Controlled or pre/post studies of the effects of BWE using auditory or visual stimulation were eligible for inclusion, provided pulses of light or tone were delivered at frequencies hypothesised to have a beneficial effect or in line with a protocol addressing clinical outcomes. Studies were required to report clinical or psychological outcomes (measured using standard methods or as deemed appropriate by peer review) and to report statistical analysis. Studies of outcomes such as electroencephalogram (EEG) response or neurotransmitter levels were not eligible. Case studies were excluded.

Isochronic tones are basically just a single tone with the volume being turned on and off at regular intervals. When you apply the same effects to music or a noise, it’s usually referred to as amplitude entrainment effects (in Mind Workstation anyway). When you apply the on/off effect to music or noise it’s usually done by targeting a specific frequency range in the sound and only turning that part on/off, leaving the rest of the music/noise untouched. What that does is allow parts of the music/noise to play without being distorted/interrupted, making it sound more pleasant to listen to. It produces a kind of fluttering sound as I like to call it and you can adjust the level of intensity.

What happens when you meditate using the Profound Meditation Program 3.0 is that instead of statically giving the nervous system the same level of juice every day, you consciously attune and intuitively adjust your nervous system and your energetic system’s unique stimulation recovery cycle. With PMP 3.0, you have a type of system with enough carrier frequency power and biofield amplitude to push your nervous system and your energetic system for a lifetime—and it is a system as dynamic as your growth and recovery cycles are. This system will enable you to push your spiritual development and growth much more quickly, recover much more quickly, and experience less overwhelm.
Audio-Visual Entrainment (AVE) is a technique that utilizes pulses of light and sound at specific frequencies to gently and safely guide the brain into various brain wave patterns. By altering your brain wave frequencies, you have the ability to boost your mood, improve sleep patterns, sharpen your mind and increase your level of relaxation, all with the simple push of a button!
Use traditional meditation to create the changes in the brain that lead to the benefits I’ve described here. Of course that means going through a long learning curve while you master the art of meditation, motivating yourself to sit each day to meditate. And, to get the benefits I’ve described, you’ll need to meditate several hours each day), and continue in that way for 30+ years.
In 1956, the famous neuroscientist W. Gray Walter published the results of studying thousands of test subjects using photic stimulation, showing their change in mental and emotional states. He also learned that photic stimulation not only altered brainwaves, but that these changes were occurring in areas of the brain outside of vision. In Walter’s words:
Much of what is currently written about brainwave entrainment, especially on the internet, is simply … incorrect.  It seems par for the course that when something of huge value is discovered as a potential ‘internet product’ that it is going to be marketed within an inch of it’s life. And often with less than stellar regard for actual science, research, or factual knowledge. 
In the past, the most common method of inducing specific brainwave states was through the use of binaural beats. One specific beat was played in one ear (through stereo headphones) and a different beat was played through the other. What the brain would naturally do in hearing these variated beats was create its own beat from the combination of the two (ie if a beat at 100 Hz was played in one ear, and a beat of 110 Hz was played in the other, the brain would resonate at 10Hz). Aside from this directing the brain into a specific state, it also causes the two hemispheres of the brain to synchronize, promoting whole brain functioning. More recently, other methods have been discovered for inducing specific brainwave states, such as isochronic tones, and monaural beats, but the bottom line is that
The same goes for brainwave entrainment.  You can’t just listen to an audio as many times as you want and expect that more is always better.  In a very real way, you are “exercising” your brain.  You are pushing it to build new neural pathways, to communicate with itself in new ways, and to adapt to a new kind of mental stimulation.  This is incredibly good for you, but there is a limit that you must observe.
Participants in the included studies were children and adults, either healthy or with conditions such as learning disabilities, attention deficit hyperactivity disorder, migraine, stress, anxiety and myofascial pain. Interventions included single, alternating, ascending or descending frequencies of photic or auditory stimulation or audiovisual entrainment selected either by the participant or by the investigator. Nearly half the studies used single sessions and the rest used multiple sessions ranging from nine to 100. Length of session varied from 0.5 seconds to 60 minutes. Frequency of session varied from twice daily to weekly. Outcomes reported in the review included cognition (including verbal skills, performance skills, attention, memory and overall intelligence/achievement), short- and long-term stress, pain, headache/migraine, mood, behavioural problems and premenstrual syndrome (PMS).