Right fuses for MF2300? Frustrated with CJ lack of help

[Music Lover]

I need new fuses for my MF 2300. There are 4x 6Amp and 1x 10 Amp. Conrad Johnson's manual only says:
10 amp-slo-blo, 6amp fast-blo- That's it.

On the internet there are a lot more fuses available with that info and more terms like time lapse, glass, copper core, length etc. I have no idea which one to choose. I called CJ and they would not give more info (amazing!) and suggested that I should buy from them at $5 per one 6-a fuse (the 10 amp is more) + shipping. Therefore 5 fuses will cost me north of $40.00.

Besides being way overpriced, I am shocked at Conrad Johnson's unwillingness to provide the most basic information to allow us to maintain their product. I politely asked for more precise info, they wouldn't give more. I asked to talk with a supervisor, she said the only way to do it is to send an email. I did. Still no response.

Are these fuses the right ones?
https://www.amazon.com/dp/B07V3DN4VW/?c ... dp_it&th=1

https://www.amazon.com/dp/B07DSSHMYR/?c ... _lig_dp_it

Thank you so much.

[admin]

I don't have any specific specs to offer you but can't you just pull the blown fuse and measure the size (you already know the values needed and slow/fast blow)? I personally would just buy good old fashioned "slow blow" or "fast blow". If it says stuff like "time lapse", then just move on.

I had the large fuse on my ART blow about a year ago and that one wasn't even listed in the manual. But I just read the values off the fuse and got the same one.

As you found out, CJ does not release any technical specs or provide service advice. They pretty much put a stop to that to try and reduce the Chinese counterfeiters. If you need any official replacement, you have to buy from them and they will send you the right part. I suppose you can order 1 of each fuse and then try to find it on your own but in all honesty, they are not really making money of your $40 worth of fuse purchases.

[Big Dog RJ]

Yep! That's about right she goes by Admin.

It can be frustrating at times, especially when you have one of their products and seek info.... just to maintain the gear.

The thing is, if you want CJ parts or service then there's a price to pay. If you want to have a chat with the manager, get advice then buy from "elsewhere..." they're not interested in the chat. Was not the case 20yrs ago though, times have changed.
Send in an email and hope for Santa to respond.... not helpful either.

The values and fuse type stated in the manual are all that's required. If you were to contact a reputed fuse supplier and give them these details, they'll know straight away. Bussman fuses are the main supplier to CJ, try contacting them directly. I've contacted Bussman in Aus and they were quite helpful but I also purchased from my CJ importer. That was $50 each fuse! So $100 for a pair.

*Make sure you get the right type of fuse and the correct value *

Don't compromise on quality, CJ gear is not low end, hence requires the proper parts and care. It's just the nature of this fine gear.

I'm sure you'll find the correct fuse.
Cheers, RJ

[Big Dog RJ]

There was one other supplier who specialises in these types of fuses, I can't quite remember the name. They knew at once which types of fuses became they also suppy to most highend audio dealers. If I can look up the name somewhere, I'll let you know.

Cheers, RJ

[admin]

Don't compromise on quality, CJ gear is not low end, hence requires the proper parts and care. It's just the nature of this fine gear.

I think this is a pretty good take home message. Every CJ unit is 4 or 5 figures. Do you really want to spend your time and take a risk of damage so you can get some fuse for 25 cents instead of $5?

I know you can get those cheap no name brand Chinese fuses for pennies. But remember, the fuse is the one thing in your MF2300 that is solely there to protect it from being damaged. Do you really want a few dollars savings to potentially compromise that protection?

[Music Lover]

Thank you all for the replies. I definitely don't want some cheap fuse that would fry my equipment. So, yes if you find the supplier please let me know.

I like my CJ equipment and it's not about the $40.00. I just have a mental (Quixotic) block buying the fuses from CJ, if they are not willing to provide the info they should. It just ain't right. Certainly when this equipment croaks I won't buy another one from them. But it seems to last forever

[admin]

I know it sometimes can be frustrating as you know they could provide the exact manufacturer and specs. They've made the decision not to due to quality control issues (perhaps financial, but again, they are not making any money on selling fuses). But at the end of the day, you really do have all the info needed to find a replacement fuse. It's going to be a certain amp rating, slow or fast blow, and the size you can measure. That's all the info you really need to buy a replacement. I'm actually surprised that this is not written on the actual fuse, it usually is in small etched markings.

[Joe Appierto]

Fuses tend be either small (5x20mm) or large (6.3x32mm). I used the word "tend" because the large fuses in my Premier 140 amp were 38mm and not 32mm in length. So admin's advice is your best bet: if it's a large fuse then measure it. The manual (and the markings on the fuse end caps) will tell you their amperage and whether fast-blow or slow-blow (also sometimes designated with a "T" for timed instead of slow).

As you've seen in the manual, the single mains fuse is 10 A slow-blow and the four B+/B- rail fuses are 6 A fast-blow.

[roberto]

Here is what the manual says regarding the fuses:


Fuses: There are 5 fuses in the MF2000 Series Amplifiers. One is the ac power line (mains) fuse. It is located in a fuse holder near the power cable. The other four fuses are in the main DC power supplies. On the MF2200 and MF2300, these are located in fuse holders near the output jacks, labeled B+ and B-. On the MF2100, these DC power supply fuses are inside the chassis on the printed circuit board. Never replace a fuse with a value or type different from that originally supplied by the factory. Correct values and types are listed below. In the event of a fuse blowing repeatedly, contact your dealer or the conrad-johnson service department.

100/120V Mains. 220/240V Mains. B+/B-
MF2300 10A, Slow Blo. 7A, slow Blo. 6A, fast Blo.

Happy listening!

[SolderSlinger]

Can you post up pictures of the markings on both end caps?