For the love of God will someone suggest an e-stim?

[masperturbator]

At last - some actual science!

I doubt that Fauci has reviewed these findings.

Unfortunately for you, it only backs up how similar estim boxes are to the professionally designed medical devices.

We agree about that.

The pulse durations are short and the typical frequencies are in the 'medium' or 'microcurrent' ranges. Output voltages are comparable to commercially available TENS devices

True for ESTIM that is built that way, with all of the circuitry required, which is why well known boxes like 2B and Coyote are well known, both for their safety and for their dissatisfaction after frequent use.

If you don't want to try estim - don't try it. It's your choice. But unless you've got some real proof that it's dangerous

I've tried it. There's plenty of proofs and discussions of dangers, and among them are the differences between over-the-counter, prescription, and clinically observed TENS/EMS for medicine.

stop interfering in things you know little about and leave the rest of us to discuss it in peace.

Don't upset the users, and I obviously can't have used it, right?

[LondonGent]

If you don't want to try estim - don't try it. It's your choice. But unless you've got some real proof that it's dangerous

I've tried it. There's plenty of proofs and discussions of dangers, and among them are the differences between over-the-counter, prescription, and clinically observed TENS/EMS for medicine.

Why don't you add some value to the discussion by sharing some of that proof then?

stop interfering in things you know little about and leave the rest of us to discuss it in peace.

Don't upset the users, and I obviously can't have used it, right?

More like; Don't mistake volume for expertise. No matter how loudly you repeat your opinions, you've already demonstrated your lack of knowledge.

[jimsport]

Good to see this sort of thread. Ive contemplated getting the electrastim AXIS so I can try estim and the video teases on the site.

Good to see people saying it works fine, any sort of discussion on the topic generally leads to people suggesting a DIY which i personally have no interest in making.

[mantrid]

Estim is safe, as long a few things are considered. Here is a conclusion -- everything already has been discussed in that forum:

• Low frequencies (including DC) are dangerous because they cause electrolysis and denaturation of proteins. As lower the frequency, as lower the permissible current (0 at f=0 !).
  
  It is reported that low frequencies (less than about 100 Hz) feel stinging. Transformers block at least very low frequencies (about less than 20Hz for audio transformers). But I recommend to invest about $1 in a hi-pass filter.
• Isolation is ensured by transformer. But it is a good idea also to protect against malfunction, e.g. by protecting the Transformer (using a TVS diode) and/or by double isolation. The latter is not trivial because it is not sufficient to purchase a medical (=isolated) power supply, you also need to isolate audio input (e.g. using another transformer) or USB cable of an USB sound card (USB isolator).
• Of course voltage and/or current should be limited somehow. This typically happens by design. But a additional protection in form of a TVS diode between amplifier and transformer is a good idea.
• Commercial units (for estim or for medical purposes) use pulses. This works because neurons become insensitive for a certain time (roughly about 20ms) after they are fired. For that reason, a signal with alternating (!) pulses at a frequency of 100 Hz and a pulse width of about 250µs feels about the same a a sinusoidal signal with a frequency of 1000 Hz (similar pulse width) -- in theory. In practice it is reported that pulsed / low duty cycle signals feel stinging with DIY devices, which is an indication that there are low frequency artifacts (that may be caused by sampling / digital filters / equalizers). That's why I would recommend such signals for DIY devices only in combinations with a hi-pass filter. In that case they feel as continuous signal but drastically reduce the power induced in the body (which can't be a mistake)

[edger477]

But I recommend to invest about $1 in a hi-pass filter.

I suppose you mean adding capacitor? Where in circuit we can add it?

[mantrid]

But I recommend to invest about $1 in a hi-pass filter.

I suppose you mean adding capacitor? Where in circuit we can add it?

Yes, see this post for schematics and pictures and there for detailed measurements and calculations.

Regarding safety: There are also some rules for electrode placement:

• Not above the heart, namely not from one breast to the other one
• Not along the backbone

Regarding the initial question (device recommendation):
Choose a device that support phase modulation (and use it in 3phase mode). That opens another dimension. The DIY devices support that. I have never read about commercial units that can do that.

[masperturbator]

ESTIM play can be safe.

This will be my final derail reply to LondonGent, whom may have the last word about all of that if he likes.

More like; Don't mistake volume for expertise. No matter how loudly you repeat your opinions, you've already demonstrated your lack of knowledge.

No.

I don't understand though, why is no one taking advantage of this market if it's so simple to DIY + seemingly on-par with most commercial offerings?

It isn't so simple.

StimJim hasn't gone to market. Maybe just COVID years? I haven't asked them.

In addition to what was already shown in thread, look at the differences in skin-contact electrodes used in TENS/EMS, compared to those used in ESTIM. You should find that TENS/EMS uses carbon electrode pads and conductive adhesive gels. ESTIM uses metals, conductive rubber tubes and cords (maybe the same material as electrode pads,) the same gels, and you have to avoid lubricants that would interfere. ESTIM often involves metal, vaginal insertion, anal insertion, and sometimes urethral insertion. TENS/EMS is usually limited to a session length of about 30 minutes, with the limits prescribed or programmed into the units.

None of that even attempts to claim that ESTIM can't be safe. It says that ESTIM isn't as simple to sell as medical TENS/EMS, partly because it isn't as safe as TENS/EMS. The additional risks are specifically desired by the ESTIM players. Those risks are held by them to not be risks. Marketers of manufactured devices tend to disagree, as self-evidently expressed in the engineering and marketing decisions for TENS/EMS devices.

Otherwise, the $10 unit on Alibaba would always have a jack-me-off option.