Hi filigran
As far as I see it , if you are missing output strength in the HF & UHF areas, the reason(s) must be from one ( or a combinations of ) the following three possibilities .
(1) The custom crossover you are using was made with the incorrect value resistors.
- You can easily determine if this is the case by comparing the value of the present resistors to the values speced for the N250Ti Jubilee.
(2) Your custom crossover may have inductors that have higher than speced DCR values .
- Again, You can easily determine if this is the case by checking the DCR values of the present inductors to the values speced for the Jubilee network.
(3) The usage of Mundorf capacitors has drastically changed the "voicing" of a system that was voiced for "bypassed" , "DC-biased", "electrolytic capacitors".
- This is a possible explanation and not as far fetched as it may appear , though it relies on accepting a phenomenon that's not talked about much ( at least not around here ) . Since I've never heard Mundorf caps / I can't speak with any first hand experience on how they might effect the overall voicing of your 250ti system.
- I have found in my own studies on caps , that as caps get smoother & deeper sounding / there can be a perceived level-drop to the UHF area . I haven't found it to be measurable / but subjectively the effect is very real . I've even taken to bypassing smooth sounding networks with sharper sounding caps - just to restore a sense of "loudness" to the UHF area . Also, I find that smooth/deep sounding network legs ( a compression driver circuit in my case ) must be turned up a bit to restore subjective balance ( when balanced against woofers ) . This increase is usually confined to the neighbourhood of a fraction of a db ( maybe .5 db ).
- The Mundorfs just might be subjecting you to this effect .
- You will need to reduce the resistive padding on these 2 network legs to test out this idea .
- The problem in attempting a change to the padding ? One needs to know the AC impedance curves for the 2 top-end drivers to reasonably alter the values of the padding resistors.
- I don't have those curves to give you / maybe someone else does and can post them.
- Without them, you will most likely change the circuits' working impedance in that area. The preceeding LC components are set to work to a specific impedance. A change in working circuit impedance will result in a shift to the crossover points. Not a good thing .
Ehhh, I know the basics of R, L, Cs in the network for speakers, thank you.
The de-biasing was made in taking one capacitor of the half value and no 9V between them.