Modifying Crossovers

@ervikingo 

A few years back, Paul McGowan at PS Audio, recapped his IRS-V speakers.  Paul asked for Arnie NuDell's help with the project.  Arnie recommended Mundorf capacitors.  The Mundorf EVO Oil caps, that I mentioned, are very good for the money.  Clear, clear, and very transparent.  They helped create a palpable midrange, when I used them for a speaker recap.

Good luck. 

@gdnrbob

I would be highly suspect of anyone who thinks they know more than the speaker designer. If they know so much, why haven’t they designed their own speaker.

My 2 cents...

It’s not about claiming to know more than the designer, it is a matter of getting around the marketing price point limitations of the speaker. For the manufacturer to move from caps that cost less than a dollar each, to ones that cost $5 or more, ends up raising the price at the consumer level by much more.

The fact is, that the vast majority of speakers at low to moderate prices, are loaded with cheap capacitors, sand cast resistors, iron core inductors, that compromise the capability of the speaker. You’d be surprised how many well respected speakers, even though they may still sound good, could still sound better with better crossover components. 

What is being discussed is, swapping out the same values, with the same values. but better quality caps and resistors. I have been doing this for years, and the results are always improvements. Usually more detail, and bigger, more defined soundstage. Sometimes it is more than subtle.

But yes, many times people do know more than the designer.

Case in point: GR Research upgrade kits for Klipsch RP-600M’s with redesigned crossover. What is an unlistenable speaker for me, becomes a reasonably good one after the upgrades.

@stimpywan Thanks!

I have found some rather expensive speakers that look expensive and fitted with beautifully machined spikes to give the impression of great care and engineering chops, but have cheaped out on the XO components which are hidden from view. Push-on connectors are used on the internal wiring to speed up assembly and other sound limiting short cuts are taken. All this cost saving is doing the resultant sound no favours.

Something mostly overlooked either from ignorance or deliberate acceptance is the orientation of the inductors. If two coils are close to each other there will be coupling, this is how transformers work, where they talk to each other causing congestion and smear. Keeping them far apart helps but of course will require a larger platform causing even more problems. Another reason that the coils are not optimally aligned is because one of them needs to be mounted, not lying flat, but upright on the rounded part which makes mounting it more difficult and time consuming.

If they are mounted correctly then they can be placed close to each other with virtually zero coupling. This happens when they are positioned as two links of a chain would lie.

Then there is the internal wiring, nasty sand cast resistors and the almost exclusive use of PCBs. Yes, there is much that can be improved. We are not talking about redesigning the XO circuit but improving what is there by replacing components with same value but better parts.

When I work on optimising the XO I endeavor to remove any terminals using brass. Those great looking chunky speaker terminals are bad news. Usually the brass, IACS about 27%, is first plated with nickel, IACS about 24%, which polishes to a high finish, and then gold plated. The polished nickel allows for a very fine looking and attractive finish. So, many dissimilar metals playing havoc with your precious audio signal. The push-ons are also brass!

For the manufacturer to move from caps that cost less than a dollar each, to ones that cost $5 or more, ends up raising the price at the consumer level by much more.

...and just to be clear, people are generally not upgrading $1 capacitors to $5 capacitors. Just go out to Parts Express or Parts ConneXion, choose a capacitance (like 0.1uF) and look at the range of pricing. Want to spend $431.68 on a single cap? You can do it! Image what a crossover full of premium parts would do to the price of a speaker.