OK, so I'm getting ready to order. I think we have settled on option 2, so here's the general idea :
- Interconnect cables (about 1.5 m) : 3.5mm TRS minijack --> Mini-XLR
- Headphone cables (30 cm) : Mini-XLR --> 2 x [Headphone connector, depending on the headphone]
My question may seem trivial but it's been puzzling me :
Mini-XLR 3P or 4P ?
It all boils down to this now. Pros/Cons please ?
I would think that 4P is more appropriate (that's what Hart Audio use in most of their custom cables (
HC-5,
HC-7,
HC-9...).
However, 3P would allow me to use standard (and cheap) interconnects like these ones that can be found on Amazon, since a lot of cans use a single mini-XLR 3P for stereo purposes (the 1990 Pro, many AKGs...) :
https://www.amazon.fr/HILABEE-Câble-Rechange-K240S-K240MK/dp/B07L67X8VT
https://www.amazon.fr/remplacement-...240-MK2-Pioneer-HDJ-2000-casque/dp/B07CBV7TBP
What do you think ? Thank you.
Option 4P Pros:
-- No need to replace all the custom headphone connectors if in the future you decide to use balanced HP output from replacement amps, versus so needing for the 3P HP connectors in Option 3P
-- Ability to match cable wire across custom-built interconnects and HP connectors, versus possible mismatch using pre-built interconnects in Option 3P
Option 4P Cons:
-- Possible higher cost now of two custom 4P interconnects versus common pre-built 3P interconnects such as you linked to, and longer lead time of custom-built versus pre-built
-- Possible marginal higher cost now of 4P HP cables, versus Option 3P
The decision hinges on how unlikely you believe it is that you would want to change to using balanced HP output from any future replacements for your dual L30s. Bear in mind that almost every HP amp with balanced output also provides single-ended output. Assign a numeric probability P(bal) to the event E(bal) of switching to balanced HP outputs, such that 0 <= P(bal) <= 1 at some average years away. Estimate the differential cost penalty C(Opt3P) associated with Option 3P (mainly the cost of replacing the custom HP connectors), as well as the differential cost penalty C(Opt4P) of Option 4P based on the differential costs of the Cons listed above. Using the formula Risk R(E) = Probability P(E) x Cost penalty C(E), calculate R(Opt4P) = 1 x C(Opt4P), as well as R(Opt3P) = P(bal) x C(Opt3P). You want to minimize the risk associated with your decision: if R(Opt4P) is significantly less than R(Opt3P), you would rationally pick Opt4P, and vice-versa. If R(Opt3P) and R(Opt4P) are roughly equal, the decision comes down to a fair coin toss. The twist as compared with the usual risk assessment situation is that the differential cost penalty of R(Opt4P) is due now, versus the differential cost penalty of R(Opt3P) being due at the likely future date you assign to the event E(bal). If P(bal) = 0, and C(Opt4P) > 0, then obviously you go with Opt3P. If C(Opt4P) = 0, then there is no reason to not go with Opt4.
I cannot think of any other significant pros and cons. An additional possibility may be that (copying your idea for the 3P interconnects) you may be able to implement Option 4P at a lower cost than above, by using pre-built interconnects with standard XLR on one end and mini-XLR 4-pin at the other, if you can find ones long enough for sale. You would need to supplement these with two pre-built short 3.5mm single-ended to XLR adapters, which would be the only pieces needing to be replaced in case E(bal) occurs in the future. The downside is that an extra juncture between cables is involved, with the accompanying risk of imperfect signal transmission.
