General thoughts:
In most cases we get the most immediate change or improvement when upgrading capacitors for the positions that are in direct line with the tweeters and mid-range drivers .
Exchanging or upgrading the induction coils can also have an impact on the sound and performance of a speaker system, but it will in it’s nature often not be as profound a change, as when changing or upgrading capacitors.
As an example it could make quite an audible difference to exchange a ferromagnetic cored coil for the mid-range or tweeter section with an air core wire or foil based inductor.
This of course only makes sense if the ferromagnetic cored coil is causing audible distortion or noise.
For vintage speakers specifically:
When upgrading your vintage or new speakers using either completely re-designed crossovers or by upgrading the stock crossovers with better components, it is important to ask yourself two questions:
- Do you want your speakers to sound different or “better” according to more modern notions of how speakers “should sound”?
- Or do you want to keep the original “vintage” sound of your speakers, even if that means sacrificing things like increased transparency and detail richness that can come from a crossover redesign and/or by upgrading to modern superior crossover components?
DIY c rossover upgrade kits for vintage speakers:
Jantzen Audio offers some DIY crossover upgrade kits for a handful of vintage speaker models, which were all re-designed by loudspeaker designer, Mr. Troels Gravesen.
The idea behind the re-designed crossovers was to correct what Mr. Gravesen perceived as inherit shortcomings and to make the speakers perform at their full potential.
We would advise that you read Mr. Gravesen’s articles for the re-designed crossovers and the feedback from customers who upgraded their vintage speakers using the re-designed crossovers, before deciding if it is right for you.
General things to consider before taking on an upgrade project:
- Do you have the required experience with crossover assembly?
- Will there be room in your enclosures for the larger crossover boards that upgrading to better components will most often require, or are you willing to make external crossovers?
- Mostly relating to vintage speakers, what is the condition of the drivers and are they in proper working condition?
If not, your first step should be to have your drivers repaired / refurbished! - If the drivers are not in optimal working condition, you cannot be sure that the driver(s) will perform the same as it/they did some 30-50 years ago, thus the crossover may need to be redesigned with the necessary changes to factor in frequency response, phase, and impedance.
Considerations for resistors:
If you are going to upgrade your crossovers and spend both time and money on the project, you may as well also upgrade stock (lower-grade) resistors to some higher grade resistors for example wire-wound, metal oxide or thick film.
Considerations for capacitors:
Generally we would recommend concentrating on upgrading the capacitors that are in direct line with the tweeters and the mid-range drivers.
This goes for both newer and vintage speakers.
For the tweeter and mid-range capacitors, it generally makes sense to use high-end (expensive) capacitors.
For the bass section we recommend simply using good quality electrolytic, MKT or Standard MKP capacitors, as it is overkill to use high-end capacitors for bass section dedicated capacitor positions.
In vintage speakers, the stock electrolytic capacitors could be 30 or more years old and could have issues with evaporation, etc. and it is likely a good idea to test their capacity and exchange them if needed.
It is also important to note that specifically for vintage speakers, the capacitor values used were often from the “old e-row” of values and today it is rare to find values like e.g., 1, 2, 3, 4 and 5uF when it comes modern era high-end capacitors, which are most often only offered in the “modern e-row” of values (e.g, 1.5, 2.2, 3.3, 4.7 uF etc.)
There will therefor often be a need to couple two or more capacitors in parallel to obtain the right capacitor value – take this into account when simulating the new and larger crossover boards.
Considerations for induction coils:
- What is the condition of stock inductors and is it necessary to exchange them?
- If you want to exchange / upgrade the stock inductors, you will have to pay extra attention to the ohmic resistance of the coils (DCR), as this may be an essential part of the crossover functioning.
- If you wish to exchange the stock inductors, it is necessary to measure the Ohmic resistance of the inductors with a precision milliohm meter. A standard multimeter is not good enough for this, as we are measuring resistance of e.g., 0.1-0.5 Ohm.
- Do your speakers have L-Pads/Attenuators, and do you have the know-how to transfer those to the new crossover boards? Alternatively, would you be willing to sacrifice such features when upgrading the crossovers?
Design of new crossovers:
- We cannot offer to design custom new crossovers for both vintage and newer speakers.It would require that we had the speakers in the workshop, which is an extremely time consuming and unrealistically costly task.
- We can offer general advice about component upgrades, if we receive all the information in the checklist below.
Checklist for component advice:
- You will need the crossover schematics with component positions and values (including DCR values for the coils)
- You will need to make good quality photo(s) of your stock crossovers that clearly show what type the stock coils, capacitors, and resistors are
- You will need to send us a full list of the component values, positions and where they are located (bass, mid, tweeter sections).
- You will also need to send us the crossover schematics and the photo(s) of the stock crossovers
Example of a stock vintage crossover versus a new upgraded one:
