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kc613
02-17-2012, 12:33 PM
thanx to David F and Grumpy for jumping in to answer my questions in my last post, much appreciated guys.
replaced all caps with Dayton 1% metallized caps, and Audiocap film and foil for the bypass caps. talk about large caps! had to install some on the back of the board, then make some wooden riser blocks(1 1/2") to mount them to the back wall. worked out great. when A/B ing them with another set of stock 4412's there was a noticeable difference right from the start, and got better with more hours of listening. this was my first experience with burn in(at least it sounded that way). took the stock 4412's out of the system(4 channel), because now they didnt sound that good, and replaced them with some L112's i have. the L112's originally sounded nicer than the 4412's but with the recap the 4412's sound better. now i have to redo the stock 4412's. if caps gave that much of an improvement, i was wondering how much of an improvement replacing most of the components on the board would be. there are 2 metal core and 2 plastic core inductors on the board with 24-26 awg wires, along with 3 resistors. i was considering air coils by Jantzen(18 ga) and Mills 1% resistors. a few questions here:

is the difference in wire size a factor(coils)? would the air coils be an improvement? i can match the values of 3 of the inductors, but, the 4th is a 2.8mH and there is only a 2.7mH value available.(parts express). will that do? this is in the LF circuit, so i would really like to replace this one as a priority. can i mount these vertically with hot melt? i can match resistor values on 2 of them, but the third will have to be a combination. would you wire these in parallel, like the caps to equal the value? the original resistors are 10w, i assume the Mills 12w resistors would be ok to use? would increasing wire size, from input connectors to the board, and from the board to LF driver help(as someone suggested) or is this a non issue?

off topic for a sec: thinking of trying active xovers and a multi amp system in the future(doing some preliminary homework now) would using a pro audio xover(Ashly xr 4001, could not afford the high end DEQX)be the right direction or is this a step down in home audio? one more question and im outta here, some thoughts on 4641's for subs?

thanks guys for the direction, it is really appreciated, especially when it comes to increasing the quality of sounds my 66yr old ears hear.

Don C
02-18-2012, 08:42 PM
The reason to use coils with a ferrous core is that this increases the inductance, so you can use a smaller, cheaper coil to have the same inductance as a much larger air core coil. It works fine, except at high power levels, when the core can saturate, changing,(reducing) the inductance. So, if you listen at very high power levels, air core coils may be a worthwhile upgrade. You'll probably notice no difference when listening at typical listening levels.

duaneage
03-05-2012, 07:37 PM
Get the 2.7 and wind it up to 2.8 by adding wire of the same gauge and giving it a few turns while measuring the value.

grumpy
03-06-2012, 06:48 AM
... or go big and unwind :)