Hi AnthonyA
Thanks for confirming the use of MP915 caddock resistors.
Note for all - as needed:
The latter part is also suitable when mounted on heatsink. The leads spacing are the same as MP930. However there are 2 issues that require some easy work:
1) mounting hole for heatsink is smaller than 3m screw. Need to increase the size by using a 3mm drill bit if you use a pre-drilled 3m hole heatsink. It does not damage the resistor and I have confirmed by measuring.
2) if your heatsink mounting hole is in the middle of length then you may either have to cut one part of the heatsink so the caddock leads can be soldered inside the FSSA pcb or you can use a tap to create a hole at a lower position on heatsink.
If you use MP930 there is nothing required to do.
Unfortunately I had already ordered so I have no more ntc...
Fab
Hi Guys,
Sorry for the stupid question, but still very confused with DC LS protection and delay kits... I never had to buy these as this is my first amp from scratch, and I don't want to risk my beloved LS. All I want is a non expensive device that protects my LS, while not ruining the DF and having a reasonable switch on delay to avoid "pops". No rocket science I thought but...
My understanding is I should stear clear from UPC1237 units as all are fakes nowadays and not failsafe at lower voltage than 25V.
But finding a board that has low resistance relays (OMRON?) and not that chip is not easy, not to mention there are apparently convenient devices running directly with 220V so not requiring any additional transformer... but are they good and do they include an anti-pop delay?
Anyway, here are 3 links corresponding to the best I found until now. If anyone could be kind enough to recommend me one of these, or whatever suitable, for the FSSA it would be much appreciated.
Assembled 30A High Power Amplifier Speaker Protection Board Module AC 110V-220V | eBay
30A Amplifier Speaker Protection Board Module With Power Integrated AC 85V-265V | eBay
Assembled 30A Stero Power AMP Amplifier Speaker Protection Board Module | eBay
Many thanks for your help
Claude
Sorry for the stupid question, but still very confused with DC LS protection and delay kits... I never had to buy these as this is my first amp from scratch, and I don't want to risk my beloved LS. All I want is a non expensive device that protects my LS, while not ruining the DF and having a reasonable switch on delay to avoid "pops". No rocket science I thought but...
My understanding is I should stear clear from UPC1237 units as all are fakes nowadays and not failsafe at lower voltage than 25V.
But finding a board that has low resistance relays (OMRON?) and not that chip is not easy, not to mention there are apparently convenient devices running directly with 220V so not requiring any additional transformer... but are they good and do they include an anti-pop delay?
Anyway, here are 3 links corresponding to the best I found until now. If anyone could be kind enough to recommend me one of these, or whatever suitable, for the FSSA it would be much appreciated.
Assembled 30A High Power Amplifier Speaker Protection Board Module AC 110V-220V | eBay
30A Amplifier Speaker Protection Board Module With Power Integrated AC 85V-265V | eBay
Assembled 30A Stero Power AMP Amplifier Speaker Protection Board Module | eBay
Many thanks for your help
Claude
Hi Claude,
If you love your speakers, stay away from eBay stuff... At least from the speaker protection.
There's several projects on this forum but one that I use often is Neurochrome Guardian686 and set it up in stereo or dual mono mode:
Guardian-686: High-End Speaker Protection Circuit for DIY Amplifiers – Neurochrome
You can also use their separate PCBs:
Guardian-86: High-End Speaker Protection Circuit for use in DIY Amps – Neurochrome
These protections use Mosfets and are not likely to fail or add extra harmonics
That's what I use in my FSSA and many other amps.
Thanks
Do
If you love your speakers, stay away from eBay stuff... At least from the speaker protection.
There's several projects on this forum but one that I use often is Neurochrome Guardian686 and set it up in stereo or dual mono mode:
Guardian-686: High-End Speaker Protection Circuit for DIY Amplifiers – Neurochrome
You can also use their separate PCBs:
Guardian-86: High-End Speaker Protection Circuit for use in DIY Amps – Neurochrome
These protections use Mosfets and are not likely to fail or add extra harmonics
That's what I use in my FSSA and many other amps.
Thanks
Do
I too find these solutions very expensive, so I ordered 10 DIY SSR pcbs for around AU$20.
Here is the the thread you might want to read.
SSR for speaker protection?
Also I would not use a protection board that has a transformer on it.
Here is the the thread you might want to read.
SSR for speaker protection?
Also I would not use a protection board that has a transformer on it.
Group buy update
AnthonyA . 2 sets FSSA2 and Ntc, poly cap, sanken+ caddock, paid, shipped
nfsgame - 1 set FSSA: paid ok, shipped
Vunce - 1 set FSSA: paid ok, shipped
Stretchneck - 3 sets fssa + 4 sets of Sanken : paid ok, shipped
ClaudeG - 1 set FSSA with Sanken: paid ok, shipped
meanie - 1 set FSSA1 (toshiba driver) : paid ok , shipped
zman01 - 1 set FSSA : paid ok, shipped to Vunce
touchdown - 1 set FSSA with Sanken : paid ok
Kalamin - 1 set FSSA with Sanken: paid ok, shipped
Spind - 1 set FSSA: paid ok, shipped
Brianco - x2 stereo FSSA sets + All Sanken
topicreader - 1 set FSSA + Sanken
Tomtest - 1 set FESA : paid ok
Normally I should be able to ship the rest in a day or 2.
Fab
AnthonyA . 2 sets FSSA2 and Ntc, poly cap, sanken+ caddock, paid, shipped
nfsgame - 1 set FSSA: paid ok, shipped
Vunce - 1 set FSSA: paid ok, shipped
Stretchneck - 3 sets fssa + 4 sets of Sanken : paid ok, shipped
ClaudeG - 1 set FSSA with Sanken: paid ok, shipped
meanie - 1 set FSSA1 (toshiba driver) : paid ok , shipped
zman01 - 1 set FSSA : paid ok, shipped to Vunce
touchdown - 1 set FSSA with Sanken : paid ok
Kalamin - 1 set FSSA with Sanken: paid ok, shipped
Spind - 1 set FSSA: paid ok, shipped
Brianco - x2 stereo FSSA sets + All Sanken
topicreader - 1 set FSSA + Sanken
Tomtest - 1 set FESA : paid ok
Normally I should be able to ship the rest in a day or 2.
Fab
Last edited:
Hi guys,
I wanted to express my thanks for the replies and PMs I received.
It is amazing how much time can be wasted for such apparently simple topics. Good news once done at least you don't really have to come back on it for future projects. So, just for info in case it helps others saving a lot of time or money, here is where I stand... .,Please note I haven't tested these options yet...
So...While the choice of a soft start proved to be fairly easy - I went for
100 A 5000 W High-Power soft start circuit d'alimentation pour Classe A Amplificateur Amp | eBay
affordable DC LS protection seems to be a hot debate and a far more complicated matter! At the end my sole targets were reasonable price and good (safe!) performance, rather than pure technology or fancy figures (low R quality relays good enough IMHO).
I have reduced my choice to 2 options. It is sad that today fake UPC1237 rule the market and that finding a simple non expensive device around low R Omron relays while using discrete transistors for DC detection seems to be so complicated (found one that sadly builds directly at the terminals and is low amps, another that is far too pricey).
So, the first reasonable option comes from Anthony A - thanks again for that Anthony!- and has no real negative apart that UPC1237 seems to be today all chinese fakes and that people told me to steer clear from them. No clue if "still" true or if that given units works well...has anyone tested it?
1X(Dual OMRON Relay 7812+UPC1237 Speaker Protection Board Kit for HIFI DIY G1N5 4894817985713 | eBay
Option 2 is rather interesting IMHO in that it uses photoelectric sensing rather than transistors to detect DC (is that reliable, downsides?) and so does without fake UPC1237. Audiophonics sells it aswell (more data are available on their site) and it has good reviews there. Don't mind of course building the kit, at least I can check components
Photoelectric Isolation Speaker Protection Board DIY Kit For BTL Power Amplifier | eBay
I may go for that one unless someone objects that photoelectric sensing is even more a risk - or a pain in terms of sonic quality - than fake UPC1237.
Thanks again to all for your kind replies
Claude
I wanted to express my thanks for the replies and PMs I received.
It is amazing how much time can be wasted for such apparently simple topics. Good news once done at least you don't really have to come back on it for future projects. So, just for info in case it helps others saving a lot of time or money, here is where I stand... .,Please note I haven't tested these options yet...
So...While the choice of a soft start proved to be fairly easy - I went for
100 A 5000 W High-Power soft start circuit d'alimentation pour Classe A Amplificateur Amp | eBay
affordable DC LS protection seems to be a hot debate and a far more complicated matter! At the end my sole targets were reasonable price and good (safe!) performance, rather than pure technology or fancy figures (low R quality relays good enough IMHO).
I have reduced my choice to 2 options. It is sad that today fake UPC1237 rule the market and that finding a simple non expensive device around low R Omron relays while using discrete transistors for DC detection seems to be so complicated (found one that sadly builds directly at the terminals and is low amps, another that is far too pricey).
So, the first reasonable option comes from Anthony A - thanks again for that Anthony!- and has no real negative apart that UPC1237 seems to be today all chinese fakes and that people told me to steer clear from them. No clue if "still" true or if that given units works well...has anyone tested it?
1X(Dual OMRON Relay 7812+UPC1237 Speaker Protection Board Kit for HIFI DIY G1N5 4894817985713 | eBay
Option 2 is rather interesting IMHO in that it uses photoelectric sensing rather than transistors to detect DC (is that reliable, downsides?) and so does without fake UPC1237. Audiophonics sells it aswell (more data are available on their site) and it has good reviews there. Don't mind of course building the kit, at least I can check components
Photoelectric Isolation Speaker Protection Board DIY Kit For BTL Power Amplifier | eBay
I may go for that one unless someone objects that photoelectric sensing is even more a risk - or a pain in terms of sonic quality - than fake UPC1237.
Thanks again to all for your kind replies
Claude
Group buy update
AnthonyA . 2 sets FSSA2 and Ntc, poly cap, sanken+ caddock, paid, shipped
nfsgame - 1 set FSSA: paid ok, shipped
Vunce - 1 set FSSA: paid ok, shipped
Stretchneck - 3 sets fssa + 4 sets of Sanken : paid ok, shipped
ClaudeG - 1 set FSSA with Sanken: paid ok, shipped
meanie - 1 set FSSA1 (toshiba driver) : paid ok , shipped
zman01 - 1 set FSSA : paid ok, shipped to Vunce
touchdown - 1 set FSSA with Sanken : paid ok, shipped
Kalamin - 1 set FSSA with Sanken: paid ok, shipped
Spind - 1 set FSSA: paid ok, shipped
Brianco - x2 stereo FSSA sets + All Sanken, shipped
topicreader - 1 set FSSA + Sanken, shipped
Tomtest - 1 set FESA : paid ok, shipped
All pcbs shipped now
Let’s hope it will not take that long to reach destination with the actual situation
Fab
AnthonyA . 2 sets FSSA2 and Ntc, poly cap, sanken+ caddock, paid, shipped
nfsgame - 1 set FSSA: paid ok, shipped
Vunce - 1 set FSSA: paid ok, shipped
Stretchneck - 3 sets fssa + 4 sets of Sanken : paid ok, shipped
ClaudeG - 1 set FSSA with Sanken: paid ok, shipped
meanie - 1 set FSSA1 (toshiba driver) : paid ok , shipped
zman01 - 1 set FSSA : paid ok, shipped to Vunce
touchdown - 1 set FSSA with Sanken : paid ok, shipped
Kalamin - 1 set FSSA with Sanken: paid ok, shipped
Spind - 1 set FSSA: paid ok, shipped
Brianco - x2 stereo FSSA sets + All Sanken, shipped
topicreader - 1 set FSSA + Sanken, shipped
Tomtest - 1 set FESA : paid ok, shipped
All pcbs shipped now
Let’s hope it will not take that long to reach destination with the actual situation
Fab