L-Pads. Speakers Awful Without Them, New Ones Ordered


I removed the L-Pads, the tweeters are way too bright, screechy above mids. Disturbing. Played my best source: R2R, Sgt. Peppers. Normally magnificent. Unlistenable!

Using my Chase Remote Control to cut Treble temporarily, until new L-Pads arrive.

I ordered these 16 ohm pads:

https://www.ebay.com/itm/153892668925

mine don’t have the issues he discusses, my insulation is modern, crossovers are tar filled metal cans, not much heat in 6.3 cu ft; these and originals were large ceramic body.

Will put the tweeter ’Brilliance’ ones in first, listen. Then add ’Presence’, listen, decide: leave in, or out. IN more than likely. They (orig and 1 set of replacements) have been IN for 62 years.

My original bronze ones came from original Fisher console, they were a custom version, still labeled ’Brilliance’ and ’Presence’.
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Many of these old Electro-Voice designs had L-Pads (16 ohm used AT37 Attenuators; 8 ohm used AT38). 2 way have one. 3 way designs have two: ’Brilliance’ and ’Presence’.

You can balance the drivers to each other, and to each space, and as you age, ability to hear highs diminishes, you can creep the tweeters up speck by speck. Imbalance due to irregular spacing: adjust each individually

I’m not going to measure and install a fixed resistor, I want future adjustability.

’L-Pads: Terrible Idea’. Bullshite, everyone who ever heard them loves them!

And, let’s not forget, the originals, with L-Pads, first one mono speaker, later two for stereo, are the designs that made these companies successful.






elliottbnewcombjr

Showing 7 responses by lewm

In the course of this discussion, I came to appreciate that you are most interested in preserving the original or vintage sound of your speakers. Which is surely a worthy goal. That is why I suggested you can keep the frequency divider network as it is, and yet improve it by upgrading the parts inside. When you put an aftermarket L pad in there, there is a risk you will come up with a sound that is quite different. I look forward to your reporting the results of installing a new L Pad. By the way, I don’t see why you say my idea is expensive. You need to buy five high-quality resistors per speaker  and if you want to get really crazy, you could also replace the associated capacitors but there is no need to spend huge dollars on those parts and the rest is DIY. There is a bUsiness, Madisound, that specializes in speaker parts. Anyway, carry on.
I promised myself to stay out of this, but on the bottom of p.2 of the brochure, Figure 3, you have a schematic of the crossover with values.  You could easily rebuild that exact circuit, at least that switchable segment, with modern high quality parts. That would change nothing in relation to adjustability and tonal balance and would probably upgrade the pure SQ, just because modern parts are better.  You might consult any number of speaker builder types on the subject of what to use.  You could have your cake and eat it too.
I don't feel put upon.  Elliot was actually quite patient with me despite my unwanted advice. Thanks.
Ralph and I go way back.  He is one of the best guys in the audio business.
OK, but I was more responding to Elliot saying that the sound was too tipped up in the treble, when he tried removing the L-pad entirely. Yes, the mechanism is different, but I thought he might ameliorate the problem with his treble control.  Anyway, the L-pad has apparently become an upgrade in the eyes of some, and I will exit the discussion as gracefully as possible.
If you have a treble control on your preamplifier, which I might guess you do have on the Mac MX110, then you can achieve much the same effect as with an L-pad.  But far be it from me to rain on your parade; I admit to my own set of eccentricities that defy pure logic.  And I would never pretend there is any such thing as "perfection" in this pursuit.  If I recommend Mills resistors, some other guy would say that some other brand or type is superior.
Oops! I see you reject the notion of using a single resistance. That’s your prerogative. Have fun. But please don’t conclude that using an Lpad is superior to replacing an Lpad with a resistor.
Like I said, Elliot.  Best to set the L pads where you like the sound.  Then measure the resistance across the L pads.  Then substitute the L pad with a high quality resistor of the value you determined by measurement across the L pad.  The best L pad is no L pad.  If you want further guidance, I recommend 12W Mills non-inductive resistors for this purpose, available by mail from Michael Percy Audio.  For better power handling, you could parallel two or more 12W Mills'.  For example, if the measured R across the Lpad at your preferred setting is 10 ohms, then buy two 20-ohm Mills from Percy and use them in parallel for a net of 10 ohms and 24W of power handling.  Or you could buy four 40-ohm Mills for 48W, etc.