Improving ALTEC Passive crossovers

[LowOhms]

Hi Guys,

Did this on my VOTT A7-800s the last couple of days, and it was really wonderful to hear. Highly recommended.

Modifying Film Cap Lead OUTS - drlowmu - Tube DIY Asylum

Have FUN, Wire is Mil Spec m22759/11 12 . YOU have to determine by YOUR EAR the amount of wire, and its gauge, to parallel, usually starting with double 14 AWG Mil Spec ( equals 11 AWG ) is a good start. My double 12 AWG may not be appropriate for most systems.

The 10.0 uF and 4.0 uF DynamiCap E, so modded, is HIGHLY recommended !!

Jeff Medwin

[BillWojo]

Wow, your really throwing a LOT of heat into those caps! No place even to attach a heatsink while you solder. Did you ever consider that you may be doing serious damage to the internals of the cap with that much heat? When soldering close to passive components I try and shunt the heat away to prevent it damaging the component. That's standard soldering practice.

BillWojo

[LowOhms]

Wow, your really throwing a LOT of heat into those caps! No place even to attach a heatsink while you solder. Did you ever consider that you may be doing serious damage to the internals of the cap with that much heat? When soldering close to passive components I try and shunt the heat away to prevent it damaging the component. That's standard soldering practice.

BillWojo

Hi Bill,

Yes, I am totally aware of the heat aspect, but HAVING the wire on the cap is FAR more important than what you discuss, in an ALTEC passive crossover !!

BTW, that is a 66 dollar cap, simply necessary, lovely, use four in the two-way crossover.

I use a Weller 250 Watt soldering GUN, Wonder Solder, and with a full head of steam, I am only "on" the piece for a few seconds, ond OFF the joint !! I find the Weller Gun excellent for doing point to point wiring on crossovers, and point to point in tube amps with precision and control.

The main take-away of my post is, MOST passive crossovers are MUSICALLY DEFICIENT, MIS-WIRED, and crossover wiring needs to be done systematically, by ear, to get it really really good. We are talking of going for full dynamics, full timbre, full musical expression.

I often revert to the use of solo classical piano playback - as a listening guide, Beethoven, Alfred Brendel playing, etc etc. Most all ALTEC passive crossovers sorely lack any form of wire optimization, a shame !!

In 2016, my present ALTEC crossover has been using TWO 14 AWG Mil Spec wires in parallel, between spans. After listening to additional wire last night, in the various spans of the crossover, I will be systematically be adding more wire ( and LISTENING to the effects ) this coming week, a third rebuild in less than six months.

I plan to KEEP these VOTTs, hence, my extreme care.

Jeff Medwin, Low Ohms

[gdmoore28]

Hi Jeff,

I'm not trained in electronics, so you will need to help me out here. What is the benefit of supplying the equivalent of 11ga wire in and out of a capacitor that contains a 22 ga wire? To my uneducated mind, it seems the equivalent of running a 3/4" water hose through a 1/4" hose, then back up to a 3/4". What am I missing here?

[bowtie427ss]

What am I missing here?

The factor known as length, and it's relevance.

FWIW, every length of wire in your system is effectively a resistor which may, or may not be of significant value to the circuit, and it's relationship to other components in the circuit. Length is a key factor in determining a wire's resistance.

Not unlike the water hose analogy, where volume of flow = electrical current, a small gauge wire of very short length can pass a pretty significant amount of current. But, just like a water hose of constant diameter, the longer it is, the less it can flow. Same with a wire of constant diameter, the longer it is, the less current it can flow.

I suspect the differences that LowOhms is hearing would be considered fairly subtle by many of us, and probably not even heard by some. I've been at this hobby long enough, and been exposed to the astute wisdom of many audio enthusiasts and professionals enough to know that there is sound theory behind his observations. When i add in the fact that he's using some of the best engineered, and most resolving loudspeaker components ever made, i have little doubt that what he's hearing is real.

[LowOhms]

The factor known as length, and it's relevance.

RIGHT !! Very good !! I try to put the first Mil Spec lead, sometimes 14 AWG, sometimes 12 AWG ( on a Dynami 4.0 E - or 10 uF E - both SUPERB for a crossover ) CLOSE - so the lead wire is 1/32nd of an inch or LESS, from the end/body of the cap. There is usually a Wonder Solder residue on the stock cap, and I try to flow the inner lead directly into that. Am on the joint for only SECONDS with the pre-heated Weller GUN.

Jeff Medwin Low Ohms