JL Audio Polypropylene 4uF Film Capacitor, ideal for signal path applications.

1 in stock

SKU: nos-jl-audio-4uf-(<1%)-polypropylene-film-capacitor Category: Tags: , , , , , ,


Capacitor Information and Performance Numbers: Tested on 5/18/20

This is one of two JL Audio Polypropylene capacitors I have for sale. There is one thing about them, there is no max working voltage given on the capacitor! However, based on the size and the materials, I can say that 100V should certainly be safe and 150-200V is likely what I’d guess it is. 

This (and the other JL) have by far the best (overall) specs of any other capacitor in this lot of capacitors. The ESR is silly low, never going above 0.38Ω and the Q-Factor was 544.3 at 1kHz (or 876.5 at 120Hz). Then the insulation resistance was spot on for a 4uF capacitor, 102MΩ. This gives a leakage current of 250V/102MΩ = 2.45 uA. Not to mention, capacitance accuracy is good down to 0.125%. (less than 1%) Finally the I/V curves are freaking great! Nearly perfect.

This may not even be a vintage capacitor, but I can’t tell you how old it is, to say it’s not one. So, we’ll just say it is one. I am going to say it’s no older than late 1970’s to early 1980’s, if I am going off the design and materials.

If you are in need of some serious capacitance accuracy as well as some super low ESR, this should be a prime candidate. In addition, it is a Polypropylene Film capacitor, which are well known to have the lowest distortion characteristics of all film capacitors (see. Linear Audio’s Cyril Bateman articles).

Dimensions: Length: 1.8″ Width: 0.6″ Height: 0.6″
Lead Length: 1.7″ (full size)

Guarantee/Return Information:
Warranty Length USA: 60 Days
Warranty Length International: 30 Days

Valid Reasons for Returning:

Capacitance is off by more than 10-20% (or whatever the cap spec is)
ESR is at least 20% higher that I reported, remembering to use the same test frequency and a calibrated meter.
Capacitor was damaged during shipping.
Capacitor won’t fit into your location.
You bought a voltage or capacitance value that you can’t use, assuming you didn’t install it, you can return it.
You experience any audible distortion with your new capacitor, I’ll let you swap it or return it. As long as the cap isn’t damaged (electrically) when I get it back.

There are many other scenarios that I might consider, just contact me if you have a question.

For customers inside the USA, I do 60 days for NOS items and 30 days for re-certified items! Return shipping will be paid by customer.

 For International buyers I do 30 days on both NOS and re-certified items. Return shipping must be paid by the customer.

Shipping and Related:

Current Shipping Speed: 1 to 3 days
Cost for US Customers: $3.49 S/H
International Shipping Rate: 
$11.49 S/H

For international, I took the average of the costs to ship to 5 countries throughout the world (Tokoyo, Japan, Poland and the UK). This is the easiest thing to do, even though it will cost me money half the time.

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Additional information

Weight 2 g
Dimensions 1.8 × 0.6 × 0.6 in

JL Audio


4 uF

Max Working Voltage

Not Shown (>100V)


Polypropylene Film

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