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Avondale Power Amplifiers

That is a very serious over-simplification. I would STRONGLY suggest that anyone should dig around for the thread where lots is discussed about the subject, including input from experts and repairers.
I don't recall that thread, so I'll take look to see if I can find it.
 
Speaker Protection Modules are good insurance, but I want to make it clear that this potential issue is not specifically related to Avondale amps. All earlier Naim amps run this same risk, including all chrome bumper and olive amps. I'm not sure if they started adding it in their later stuff.

Not quite. Naim has SOA protection and reasonable supply voltages. Many Avondale builds push the rails up which could cause thermal stability issues as well as SOA issues.
 
Again, thanks for the input!

I’ve done a forum search on “speaker protection” and read through what appear to be the relevant threads. I don’t understand all the technical stuff but, from what I can understand, it seems that a) the failures are very rare and ‘speaker protection” is a “nice to have” but not an absolute requirement and b) most of the failures occur with home builds where a voltage is set too high.

Would that be a fair summation?

Notwithstanding the above, if I did decide to add speaker protection, would it fit in the NAP 250 case? I’m assuming soldering is required so it’s not something I could do myself. Is it something that Avondale, Witch hat, CHC, etc. would take on and would it be expensive?
 
. I don’t understand all the technical stuff but, from what I can understand, it seems that a) the failures are very rare and ‘speaker protection” is a “nice to have” but not an absolute requirement and b) most of the failures occur with home builds where a voltage is set too high.

Would that be a fair summation?

No. On either count.

Car seat-belts are more than "nice to haves".

I would refer you to comments in the post by @S-Man above, which is/are precisely what I was alluding to.

Speaker protection boards, complete, ready-built, are freely available and generally need no more than some screw terminals tightening onto the appropriate stripped wires. They are around 10 x 8 x 3cm high. All the ones that I have seen have been stereo, so in mono-blocks, just half the board is used. Input voltage, to actually power the protection circuit, is generally a huge range, AC or DC.
 
No. On either count.

Car seat-belts are more than "nice to haves".

I would refer you to comments in the post by @S-Man above, which is/are precisely what I was alluding to.

Speaker protection boards, complete, ready-built, are freely available and generally need no more than some screw terminals tightening onto the appropriate stripped wires. They are around 10 x 8 x 3cm high. All the ones that I have seen have been stereo, so in mono-blocks, just half the board is used. Input voltage, to actually power the protection circuit, is generally a huge range, AC or DC.

https://i.postimg.cc/50Ch3148/92-BEBCEA-B8-AE-4607-BB1-D-CDAF44268-EF3.jpg

It would appear (see photo above) that there is no room for a 10 x 8 x 3cm module even if I knew how to wire it.

I guess I’ll just have to take the risk!
 
There is room - probably attached vertically somewhere. Then fit a small power supply TX, to power it.

Fiddly, but far from impossible.
I've often taken to mounting the speaker protection PCB on the back panel.

2021-11-28_11-19-09 by Garf Arf, on Flickr
PXL_20210328_184435583 by Garf Arf, on Flickr
IMG_20201108_093817 by Garf Arf, on Flickr

I know these are DIY builds and you would have mess up the wires in the 250 wiring harness, but still...how expensive are your speakers?
 
I've often taken to mounting the speaker protection PCB on the back panel.

2021-11-28_11-19-09 by Garf Arf, on Flickr
PXL_20210328_184435583 by Garf Arf, on Flickr
IMG_20201108_093817 by Garf Arf, on Flickr

I know these are DIY builds and you would have mess up the wires in the 250 wiring harness, but still...how expensive are your speakers?
I’ve got SBL’s with Avondale passive crossovers……I’m assuming any potential damage would be to the speakers not the crossovers?
 
I’ve got SBL’s with Avondale passive crossovers……I’m assuming any potential damage would be to the speakers not the crossovers?

Any malfunction that affects the speaker (it would only ever be one at any one time, unless you are the unluckiest person on earth), would take out the woofer. The circuit/board would obviously have predeceased the driver by a very short period.

Time to fit speaker protection for someone set up for the job? A couple of hours? Just to give you some idea of what anyone might charge to do the deed.

Prices for the circuit can be found on EPay, but pretty cheap.

Les might well offer to do the job, but if his schedule is as normal, there'd be quite a wait.
 


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