Soft Start & Speaker Turn-On Delay / DC Protector Combo

I used the soft start which seems to be doing the job just right. I am using it on a 75w/ch class A amp running two 500va transformers. It has done the job well. I used a 0.47UF for the snubber in C2.

I may still build the Speaker protector board

Built 2 pairs. These boards are quick and easy to build and work great. Would highly recommend!

The documentation for the soft-start board is a bit stale, but generally adequate. The PCB quality is first rate, and the overall design is good as well. I substituted an Omron GSLE-1A4 (24Vdc) relay because the specified part was no longer available. It fits and works well. This relay has a 10 amp rating @ 250Vac. I used a 1.0 uF MKT X2 rated capacitor for the input power supply. Smaller capacitors I experimented with, did not seem to supply adequate current. I wanted a long delay, so I up-sized the timing capacitor to 4700 uF, which gave me about 2.6 seconds delay to relay closure.

I bought this kit to add to a commercially produced amplifier that is direct coupled. Due to it age, some of the components have drifted and the amp started to have some instability at initial power up and while shutting down.

The circuit boards are not all that large and I had plenty of room to install them in my amp. The boards themselves are of high quality. As others have said, I had to deviate a bit on the relay selection from the supplied BOM. I used two of the Omron G5LE-1A4-DC12 for the speaker delay and one Omron G5LE-14-DC24 for the soft start. For the transformer, I used a Triad F5-24. The kit is super easy to assemble and it works perfectly, the delay timing is perfect as my amplifier is stabilized before the speaker jacks are active now.

Thank for a great product, I plan to buy more in the future to add to my other Direct Coupled amplifiers.

I am using only DC protection board, It is a very nice board, I ordered different series resistors than those mentioned in BOM, so mine were bigger, be mindful of that. Also I am going to use part# G5LE-14-DC5 for Relay, please check before ordering component.

Good shipping. High quality board.. There is no reason to do point-to-point wiring. When you have a high quality board like this.

Good quality PCBs. I installed all the components but i didnt have chance to test the function

Good quality and easy to assemble
I used two of these combo to build two F5 power amps in mono configuration. PCB quality is really good and it does the job really well. Good documentation also.

I used two of these combo to build two Honey Badger power amps in mono configuration. PCB quality is really good and it does the job really well. Good documentation also.

Boards arrived within 2 weeks to the UK. The board build was straightforward, attached to the rear panel of my F6, delays full current for a few seconds with no turn on noise through the speakers. Great product.

Awesome fast shipping and worked perfectly! Thanks!

What can I say. Always nice parts and fast delivery.

Hi.
I have received everything well and it looks very good quality.
I have already mounted all the components on the PSU board and the rest as well, but have not been able to test it yet.
I have another order for an F5 kit pending and I think some other item, but I imagine it will be stopped at customs.
I am eager to receive it and be able to finish the project. Surely this will be the first of several (looking at the quality of the material, I am already waiting for there to be stocks for an aleph J).
I hope that at least it brings back memories of an pass labs aleph 0s that I had years ago and that I will always regret selling.
Many thanks to diyaudio and first Watt for giving us the opportunity to enjoy these projects.

diyaudiostore is just as reliable as a shop could be. Plus, they're friendly, helpful, and have a sense of humor. They make one feel a bit at home.

Good overall

The board quality is very good. Very nicely done.
I used the board with a Amp Camp amplifier and found that the relays would oscillate for several seconds until they finally settled.
When the amp turns on there is a charge transfer across the output cap. Without a load on the amp the voltage causes the control circuit to sense a fault and turn off. The solution seemed obvious to me so I didn't spend a lot of time analyzing the problem. Instead I put a 25 Ohm 10 W resistors on the normally closed relay contact to ground. This dissipated the turn on voltage pulse. This made the amp happy again. The value of the resistor was a what I had on hand at the time and wasn't anything special. An 8 Ohm might work better, but it would dissipate more power at turn on as the amp starts up with a signal present. I will try the 8 ohm resistors when I get around to it.

I'm building a pair of mono block F5t v3 balanced amps, I bought two sets of the soft start and speaker protection pc boards. With a 800 va 36v secondary torroids, the soft start I felt was a requirement. The speaker protection boards I wasn't going to use until several people explained the DC coupled amps can destroy my speakers if DC leaked to the outputs. The only interface with the audio signal is through the relays so no big deal. I'm glad they are sold together. Thank you diy!

arrived promptly as ordered, cant wait to start the next project

Products where bought to be used with my de-lite amp I'm building as it's told that it has a turn on thump. The boards from diyaudiostore are of the top quality as you come to expect. Nothing short of perfect.

The pcb quality is good, i am happy with the board and the quick delivery. Yet, really appreciated if the official building guide is attached (or a link is fine enough). The reason is the thread not easy to follow. I wish to make it work first then dig into the thread to modify the board. Thanks

4 our of 5 stars because the relay sourced in the BOM is no longer available and not updated. I did find a replacement after some digging at Mouser. Easy assembly and worked as designed.

Must have for Aleph J. Absolutely silent turn on and off for the Aleph J.

Well laid out boards nice quality items. Highly recomended.

Soft Start & Speaker Turn-On Delay / DC Protector Combo

Very good boards supported by threads. Fast delivery at good price.

I purchased the boards but have only assembled the DC protector circuit. Boards are of high quality - no issues at all. Shipment was quick.

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