Audiophile Fuses: Worthwhile or "Snake Oil" ?

[AnotherJohnson]

An observation about OEM style Bussman fuses.

The Audio Research REF 250 SE uses MDQ-7 Bussman 7 amp 250V Slo Blo glass fuses to limit the line draw.

I wanted some spares, but locally the closest available was Bussman MDL-7-R, with the same nominal rating, but slightly different Slo Blo profile.

I asked ARC about the possible substitution and the response was that it should be OK but that they use the MDQ.

I looked up the cold resistance and it is 13 milli Ohms for the MDQ and 18 milli Ohms for the MDL.

The price of the MDQ is five to 20 times as high as the MDL, depending on the supplier.

.013 or .018 both look like 0 to an electrician.

But in these audio amplifiers it would be observed as a significant difference in the attempt to drive the impedance to 0.

So … I’ve ordered a tin of the MDQs.

[admin]

Will it make a difference, who knows? But we are in the same discussion about how much we should skimp on accessories when the amp costs $17k?

As the famous quote goes here on CJO, "buy the best and cry once."

[AnotherJohnson]

Will it make a difference, who knows? But we are in the same discussion about how much we should skimp on accessories when the amp costs $17k?

As the famous quote goes here on CJO, "buy the best and cry once."

$38k msrp for the pair before they were discontinued. I don’t care about $1 vs $5 for fuses.

I think the question is “Is the MDQ the best? Or would a $200 aftermarket fuse be better?”

Eaton makes them both, and when you look at them, it is easy to see that the MDQ is much more complex than the MDL. I was surprised that they even had specs for cold resistance. It must be important to somebody.

One lesson for me is that my multimeter is for electricians rather than for electronic. I need to get a better multimeter.

[admin]

Oh, I forgot it's $17k a piece. I always find it odd when they list monoblocks by price per amp, I mean, who buys just one?

I haven't gotten caught in the "audiophile fuse" thing just yet. I may in the future but I have kind of parked it in the back for now, perhaps better to stay in ignorance.

At the end of the day, listen to your ears.

[AnotherJohnson]

Oh, I forgot it's $17k a piece. I always find it odd when they list monoblocks by price per amp, I mean, who buys just one?

I haven't gotten caught in the "audiophile fuse" thing just yet. I may in the future but I have kind of parked it in the back for now, perhaps better to stay in ignorance.

At the end of the day, listen to your ears.

They blew them out at the end for $17k/pair after they’d been discontinued

At the end of the day, listening to your ears can be very expensive .

[AnotherJohnson]

I found an old ad. The blowout was a small number to eliminate inventory and the price was $17995 per pair. $18995 per amp had been the last price before the retirement.

Not that it matters.

But they do look, sound, and act like one would expect of big ARC monoblocks.

[AnotherJohnson]

The two 7 amp 250 V Bussmann Slo Blo fuses are

MDL-7-R on the left and MDQ-7 on the right.

3736CCD7-655E-43A3-BAAA-7ADBDA503530.jpeg (4.12 MiB) Viewed 299 times

MDL-7-R has 18 milliamp cold resistance.

MDQ-7 has 13 milliamp cold resistance.

Both 0 to an electrician.

The MDL costs about one to two bucks a piece. The MDQ costs about 6 to 15 bucks a piece.

MDL made in China. MDQ in Mexico.

After experimenting, I declare the MDQ-7 as the sonically superior in the Ref 250 SEs at my house.

I am only now beginning to understand the ramifications of ARC’s claim to be High Definition.

[admin]

The MDQ does look fancier with that internal design. At the end of the day, you have to listen to you ears. You shouldn't have to replace fuses too many times so it's a modest investment for improvement in sound.

[AnotherJohnson]

The MDQ does look fancier with that internal design. At the end of the day, you have to listen to you ears. You shouldn't have to replace fuses too many times so it's a modest investment for improvement in sound.

Actually there’s no cost. ARC uses the MDQ-7 as the OEM fuse.