Leslie speaker crossover...........122/147.......251 replacement.

[zernos]

For anyone thinking about replacing their vintage 528 crossover, I would strongly recommend the crossover being sold by Tonewheel General. Rick builds the unit. 140.00 + shipping. When you hear the sound improvement over the existing crossover, you will thank me for the suggestion. The improvement is outstanding!

[JoeyB3]

No need to replace entire unit when you can simply swap out the capacitors inside yourself for a few bucks. Those vintage inductors are not something you want to simply discard.
If you are missing the entire dividing network and don't wish to go hunting a vintage one down, then TWG is of course a viable solution.

[Jyvoipabo]

I agree.

I enlarge the picture of the TWH filter
I see 2 capacitors of 6µ2 paralleled.
That is 12µ4 and there is a 12µ5 on the genuine Leslie filter.

I bet the Twh filter is exactly the same as the original Butterworth but with new capacitors.

JP

[David Anderson]

I bet the Twh filter is exactly the same as the original Butterworth but with new capacitors.

The original Leslie crossover is not a Butterworth formula crossover; it's based on the m-derived half-section calculations from Zobel's work.

As far as I know, the TWG crossover is an exact copy of the original with higher-quality components. There was never any claim that it was anything other than that.

[zernos]

TWG crossover.

The original Leslie crossover is not a Butterworth formula crossover; it's based on the m-derived half-section calculations from Zobel's work.

As far as I know, the TWG crossover is an exact copy of the original with higher-quality components. There was never any claim that it was anything other than that.

Thank you David. I only suggested the TWG crossover to help. The components are without a doubt higher-quality including the coils have more windings and heavier gauge wire than the 528. Earlier this year I purchased a 528 crossover to replace my old one. It had all new Dayton capacitors. The coils were the same. And yes, it did make a difference in the sound quality. It can't compare to the TWG crossover that I am presently using. Hearing, is believing. In closing, I know a person who was rebuilding a Leslie. He called me and asked if I had an extra crossover. I did. I gave it to him, free. That was the 528 with the new capacitors. I'm new to this forum. If I have learned one thing, keep my mouth shut and mind my own business (which I always do.)

[Jyvoipabo]

Hello,

Here a pic showing :
Right measurement of the original paper capacitor. Drift is 12µ5 > 56 = +350%. Other side value is 34µF by Fluke but the Karl-Heinz Kübbeler AVR tester more perplex say 'Unknow or damaged part'.
Left new filter with capacitors pulled out from somewhere but industrial 400V and finely ajusted for value wihin the 1%.

Final value is 12µ55 and 7µ76 for theorical 12µ5 7µ8.
Black silicon glue is a vibration protect.

JP

[David Anderson]

You're never going to hear +/-5% or probably +/-10% in crossover parts, not to mention the fact that you're counting on the fact that the inductors are also wound to 1%, which I can guarantee you they are not.

It's good to be precise, but it's better to be precise when precision matters.

[Jyvoipabo]

Thank you for this precisions about precision.

Out of curiosity i made some measurements.

L2(Treble) Measured 3.33mH (/3.2) = + 4%

L1(Bass) Measured 5.22mH (/5.2) = + 0.4%

> Total cross over mismatch including the 1% capacitor < 5%.

A few word about the cost involved to be precise.

12$ is the price of the chinese 'Component Tester Transistor Diode Inductor LCR Capacitor ESR Meter' that is good enough to made all the measurements.
Very useful in checking old capacitors and sorting news for a best result.

I'm not musician. I don't know if it is bad or good. But, in filters, i prefer to be precise. By this way, i'm sure i don't got any problems.

JP