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There are many forum members swearing by taking the two 1N3996 Zener diodes out of the circuit, just unbolt one of them from the bracket and let float to remove from circuit. I was intrigued so I felt like taking some distortion measurements to see what is going on. In theory these diodes should not be doing anything unless you reach a peak voltage of 5.737v to where they would start to conduct and clamp the signal there, nothing higher can pass. In terms of RMS power it works out to a maximum of 2 watts going into the tweeters. Testing confirmed that the diodes indeed do clamp the signal exactly at 5.737v. BUT there was an unexpected outcome to taking distortion readings below this value. Voltage readings are taken at the tweeter output across the diodes. They are peak voltages unless otherwise stated. What I found was surprising. I didn't see any difference at 2.8v, both with and without diodes had identical distortion profiles. It's when you start to reach about 4v where things start go awry for the circuit with the diodes. As soon as you near 4v distortion starts to quickly build up with increase in amplitude. The pictures below are the difference between the network with and without the diodes at 5v. The zeners are clearly starting to do something at 4v, I am guessing it's the very beginning of their 'knee' where very little current is starting to pass and the diodes are somewhere in their dynamic impedance range, datasheet shows 300uA they are 100 ohms and linearly decreases impedance vs increase in current, at 600mA the diode is .2 ohms. Regardless of the mechanism they just don't clamp at 5.737v, clearly current is passing at lower peak voltages, I am seeing 4v is where the difference is happening at. Now you might say to yourself that's still a lot of power. 4v peak is about 2.8v RMS, or 1 watt power. But you must remember dynamic range in music. If you are hovering around say 1 watt at the input of the crossover network, 20db dynamic headroom, a heavy crash cymbal may push a peak transient over the 4v for a very short period of time. 20db is 10x, so for 4v that's only around 400mV. I may be completely wrong but I can completely see even though we know the average power into the tweeter will be low, there must some signals passing over the 4v. Members have made it quite clear that taking these diodes out have impacted the sound positively, so they must be misbehaving during even modest play levels. My engineering mind was doubtful, the diodes are suppose to clamp at 2 watts and up, certainly must not be heard at in home listening levels, well it turns out that distortion is increasing rapidly at anything over just 1 watt or 4v peak into the tweeter. You may not be averaging 1 watt into the tweeter but you may hit it with dynamic music. If for whatever reason you are blasting away and you happen to reach the clamping voltage peak, distortion grossly increases, at the point of clipping you are already at 5% THD and it just gets worse from there. Clearly in home listening is reaching the point where these diodes are creating distortion and effecting the sound quality. You can see the higher harmonics jump right up at 15kHz and 20kHz.

Above is the original Peter Gabriel version With the above sentences that @dirtmudd posted Below is the Seconds Out version on Seconds Out And the Steve Hackett version with his Genesis Revisited band

But measuring answers the reasons why it sounds different which I just did the testing and can prove the diodes effect the sound. Calculations show it should clamp at 5.737v which the testing confirms. BUT, there is a big difference in distortion below that as soon as you reach 4v peak. At 1 watt, which is quite a bit into the tweeter the distortion is the same, the instant you get to around 4v peak distortion starts to drastically increase with the diodes in circuit, out of circuit it stays clean. That is not the intention of that circuit, it's not suppose to do anything or effect the sound until you reach the peak clamp voltage and then it cuts the waveform right off as it should, the distortion is obviously unintentional and I am not sure if Klipsch even knows about it. I will start a new thread to post my findings and discuss this further.

While George gently sleeps 🤪 Now for a little Prog I read on Instagram today that over 70 thousand individuals voted this album the best live Progressive rock album As Im typing this post I am listening again to Suppers Ready Artist - Genesis Title - Seconds Out Album ID - https://www.discogs.com/release/4407284-Genesis-Seconds-Out

My new vintage Tube Preamplifier DYNACO PAS 4 The preamp is equipped with a matched pair Electro Harmonix Goldpin & Gold Grid 6DJ8 NoS .The phono section with a matched pair 12AX7 Old Novosibirsk Golden Grid NoS 1972 + 2x JJ 6DJ8 Gold tubes NoS. Gonna modify him soon with Mundorf Silver / Gold and Mundorf Evo Caps as well as Silver Micas

I don’t solder so assuming it’s required to add fuses I’ll just accept the risk of no protection. Im quite sure as I indicated earlier that unless there is some sort of catastrophic failure with a piece of gear the tweeters will be fine. No teenagers left in my house.

No worries, I know what you were saying. I get it that also many don't really care why it sounds better, just that it sounds better and they are happy with the results. I was just merely stating that I like measuring things for a why to quantify why it sounds different.

Lol, the crux of the biscuit, is the apostrophe.

Well would you look at that! About darn time you decided to gace us with your presence George! I figured you were up to something. Gave birth to another tone arm huh? You dawg you! Gonna sound fantastic with you in control of the arms. Nice touch for sure! I'd hurt myself and can't imagine 3. When is the 4th one going on? lol Beautiful brother! It's cold outside and didn't roll out of bed until noon. hahaha Warmed things up and on an adventure... Been a long time since I've been out to jam nite and Covid rates are up soooo. Always nice just firing thing up and Now I see this vision posted 4 arms? 😂

I bought a new vintage Pretube amplifier a DYNACO PAS 4 The preamp is equipped with a matched pair Electro Harmonix Goldpin & Gold Grid 6DJ8 NoS .The phono section with a matched pair 12AX7 Old Novosibirsk Golden Grid NoS 1972 + 2x JJ 6DJ8 Gold tubes NoS. Gonna modify him soon with Mundorf Silver / Gold and Mundorf Evo Caps as well as Silver MIcas He´s fireing the ss power stage from my marantz pm11-S3 So now i can play 1. tube preamplifier > tube monos 2. tube preamp > transistor output stage 3. transistor preamplifier > tube monos 4. transistor preamp > transistor power amp What shall I need more ........

My close to 40 year old Micro Seiki DQX 1000 equipped with SME 3009 II Improved S2 & Micro Seiki MA 505 MK II

https://www.facebook.com/marketplace/item/469002961347489/?ref=search&referral_code=marketplace_search&referral_story_type=post Seller is asking $1200 for all of this.

Wake to a bunch of noise today, cats have a live mouse. Probably peed all over the living room during the catch and release game. The younger male finally came over to show the prize. Mouse looked pretty worked over, threw it out in the snow by the tail. Think I found the one of thier ways inside back in the corner there. Picked up some traps.

Look at this on eBay https://www.ebay.com/itm/Klipsch-Epic-Speakers-K-64-KN-vintage-replacement-tweeter-excellent-condition-/325020921950?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0

Doesn't look like they have shortened it. https://www.klipsch.com/warranty-indoor-outdoor-speakers

That's great! Thanks very much for doing the work.

Finally, some visual proof of what people claim to have been hearing. Very good work Captain!

bought this one as well L.R. Burnside " come on in "

bought this SACD a couple fo days ago Mighty Sam McClain " Give it up to Love "

This ad is from Johnson City, west of Austin. https://www.facebook.com/marketplace/item/913293329609397/?ref=search&referral_code=marketplace_search&referral_story_type=post

Both the K55 and K77 are protected by crossover capacitors from any purely DC event like a SS amp shorting outputs putting rail voltage DC at the output. The woofer on the other hand isn't. Many of the speakers that were in a pro sound application that were pushed much harder compared to home audio use were seeing tweeter damage from the newer high powered transistor amplifiers. I suspect a lot of instability burning up tweeters with high frequency oscillations that are not even heard or the very harsh clipping of a high powered transistor amplifier. The high harmonic content from the clipping grossly increased power into the sensitive tweeter and poof. The diodes were a good AC clamping mechanism that when in house tested probably did a quick A/B listening test and concluded it worked like glue so ship them out. Even if the increased distortion was known they could have felt it was an acceptable trade off for the protection.

@jason str I have found that putting the trap in a saltine cracker box helps. Give the mice a place to "hide" ... also keeps the cats away from the trap. A few hemp seed make a good addition to any bait. Mice love them.

you threw their kill out... if you let the cats out, don't be surprised to find the frozen "carcass" back in the house. Mine had a dead bird that I threw out many times, until I tossed it into a cactus. The cats were mad at me for a couple days.

You're not related to @grasshopper are you? lolol

I believe years later then mine had zener diodes in their AL crossovers. Mine were an exception for some reason. Cost Klipsch tweeters under warranty by not having them but to be fair they would never have blown with just me using them. I have since replaced the AL's with AA's.

My '86 LaScala's came from the factory without diodes. I will assume they were out of them when my crossovers were built. I have never blown a tweeter myself but years ago my teenage sons did. Replaced under warranty. To prevent it happening again I fused my speakers and have never had a problem again. If fuses have any effect on sound I did not, have not heard any difference. Knowing a little electronics I am sure fuses, being smaller then the wire connecting the speakers does have some effect, damping factor maybe, but the sacrifice is worth the cost for me protecting my tweeters. Of course someone can always replace the tweeters with some of Crites which are rated inline with the mid driver if so inclined. Another reason for fuses with me is I am always replacing and building amplifiers and fuses are good insurance as well for what I do. Many speakers come from the factory with fuses installed. I think the instructions that came with my speakers recommend 1 1/4 amp slow blow fuses but those are kinda hard to find so I just use 1 amp ones.

Sold!

“Old [Michael] went past the pet shop, which was never open, into the park, which was never closed, and the park was full of a very smooth, clean, green grass. So he took off all his clothes and began rubbing his flesh into the wet, clean, green grass. He accompanied himself with a little tune – it went like this.” Gabriel would briefly perform scat singing over Phil Collins’s drum accompaniment. “Beneath the ground, the dirty brown writhing things called ‘worms’ interpreted the pitter-patter from above as rainfall. Rainfall in worm-world means two things: mating and bath time. Both of these experiences were thoroughly enjoyable to the worm colony. Within seconds, the entire surface of the park was a mass of dirty, brown, soggy, writhing forms. “He was still pleased, old Michael, and he began whistling a tune this time to accompany himself.” Gabriel then briefly whistles the beginning of the hymn Jerusalem. ” ‘Jerusalem Boogie’ to us, perhaps. But to the birds it meant that supper was ready.”

This is why I have recommended these for many years (over 12) for LaScalas and Belles. They sound much better than the others.

Need to sleep now , it´s 1.47 am here , see you soon again .......

I was looking for a pic, but you´re faster than me ...

Come on George you can do better than that! 😂

I have only one white-bellied hedgehog

The poodle bites The poodle chews it

Allready done ...LoL ....one of my diy power cords 3 x 2,5 mm2

No you🍻

Right back at ya

That is a well designed and built preamp and produces a beautiful soundstage on all the audio spectrum With some well targeted modifications with beter quality audio caps you be in audio heaven my friend 🤘🤘

My first YES. Just as old as I am. One of three LPs bought on the german DUAL forum, just like the Joe Jackson above.

Because like many cheap Chinese tube amps they just do not perform well at all. With 1 watt it's already over 7% THD!! Where it measured 1% THD was only at 40mW of power, pretty terrible if you ask me. For comparison the circuit I am working on reaches 1% THD at 12.5 watts which is pretty good for a SE amplifier. https://www.audiosciencereview.com/forum/index.php?threads/reisong-a10-el34-hi-fi-audio-stereo-tube-amplifier-single-end-class-a-review.19972/

@MicroMara Got this one today. The cover's a bit battered, but the LP is fine:

I don’t remember ever interacting with johnlw7 (he didn’t post much) but the thread linked below is especially poignant and worth reading through. Also, underscores the warm support on this forum and something to remember when discussions devolve into arguments - political or otherwise.

Peavey FH 1 is only 6" wider than LaScala with a lower cutoff frequency and flatter response.

For sure. But baseball cards are also judged for their covers (appearance) along with who it is, what manufacturer distributed it, and so on. For collectors, it is not always about the music unfortunately. Who cares about them, except that sometimes they raise the price of what we like to obscene levels. BTW, you got the beanie babies? (crank yankers reference)

As long as there is a perpus, I won't propose a purpose.

I recently unboxed, and hooked my brand new La Scala's II, 70th Anniversary to a Cary Audio SLI-80 HS, and the sound was just beautiful. I am still experimenting, so I hooked the pair to my new MAC7200, and although I have no room treatment yet, they sounded even better. See the short video I posted on YouTube, it shows despite the poor recording via my iPhone12, the synergy these 2 have whith is other. Next, I will hook'em up to my PL Dialogue HP, and will see. PS: this was initial quick and primary setup, neither the speakers nor the Mac7200 have bene broken in, just out of the box. Source Amazon HD via Node 2i.

FWIW. I had some success with hot glue rather than spray-on adhesive. It was to lay down a long string of hot glue on the frame. Then put the fabric over it. Then apply a clothes iron to the fabric to melt the hot glue. WMcD