henry4841

The square wave does not have peaks or ring is just not as good as some of my other tube amplifiers. Using the distortion software Arta the distortion picture looks very good so I did not pursue it further. It may be something to pursue one day when I find the time. I just considered it an exercise in trying to hear what you measure.

For those that may be interested in the GU-50 tube. Others compare it to the 300b tube in SE mode. https://jacmusic.com/techcorner/ARTICLES/English/Portraits/GM50/index-GM50-Portraits.html#:~:text=GU50 is one of the most curious tubes to find.&text=Apart from the socket%2C and,you stay below 40Watt continuous. https://en.wikipedia.org/wiki/GU-50

The zener diodes are a safety measure for the delicate tweeter. That being said I do not have them in my AA's but my kids blew my tweeters on a couple of occasions when I was not at home with the AL-3's without the diodes. Not a problem now since they are gone from house. A good solution would be buy a couple of the tweeters that do not need zener's from bob and use the simple AA crossover without the diodes. The combination would probably be an improvement.

Spoke without looking at schematic, you are correct. He could remove one lead though.

I honestly do not remember being it was a few years ago but I want to say in the neighborhood of 5 or 6 watts. Plenty enough for my speakers in my room for sure with good decent bass.

My last tube amplifier build done a few years ago using some Soviet military NOS GU-50 pentode tubes run as SET's. Does not produce as good a square wave as good as some of my other tubes builds but sounds good to me. I do not know who the designer of schematic was.

You can jumper across them with some jumper wires and see if they are the problem. Will not hurt anything as long as you do not play overly loud. The original AL-3 crossovers in my speakers that were from all accounts supposed to have them did not. Perhaps they were just out of them when my LaScala's were built. I doubt they are the problem though. Bad solder connection or just bad connection from amp to crossovers might be. Swapping crossovers with speakers would be an excellent test. Check all connections first.

Those oil can caps are motor run capacitors that are chiefly used in air conditioner units in an extremely hostile environment. They are a film capacitor made to high standards and I use them in amplifier and crossover builds when possible. Many say that some of those expensive boutique capacitors are nothing more then dressed up motor run caps. All I can say is get some, test them, listen with then and see what you find. They are inexpensive for what you get. What can you lose, PWK liked and used them for a reason.

I have some of those in a crossover for another set of speakers I own. I like the sound of them.

There is a significant difference between an electrolytic cap and a film one. Any time you use a film cap in a circuit vs an electrolytic I am like you and believe it is an improvement. I am sure cost considerations were the principle reason an electrolytic was used in said network. The engineers probably decided it would be good enough and save money. Let's assume some things. if Carl takes the caps he likes Audyn with him when he test the Daytons and they test much the same then why does he prefer one over the other? If one test slightly better, few uf's better or an ESR a few 0.001, I do not believe the difference will be significant enough. This also assumes there is not some major error in the Dayton caps.There are better ways to test capacitors than the little cheap, relatively, ESR meters being sold. One I am aware of is with an oscilloscope along with some other more expensive lab type capacitor testers. Hearing is so subjective and there is so much we as human beings do not know about hearing that I do no not believe we will ever fully understand. I have an oscilloscope and signal generator but to my way thinking too much trouble. Much easier to just find a cap brand you like and stick with it.

I honestly do not know the answer to your first question. Bob Crites states on his website if they measure the same ESR and capacitance they will sound the same. I tend to disagree but I do not have the know how or ability to do so. Neither have I taken the same measured capacitance and ESR of two different caps and installed them in a circuit to see if I could tell any difference. It would take someone with the skills and superior hearing to properly evaluate the test. Being old I would surely not be the one. Someone like my grandson that can actually hear a dog whistle device and cringes when it is turned on when I like most hear nothing. But then he would also have to be trand in the audio field as well. Also the thought on there may be something we are not aware of or know how to measure that would make a difference. We learn more about what we hear with technical advances every year or decade at least. I think you are correct on your last statement. On the older AA type 1st order crossovers precise values are not really necessary. From what I have read here and other places the newer speaker crossovers with a steeper designed crossover use a lot of Myler caps which are polyester probably for cost consideration and the engineers at Klipsch consider good enough. Companies have to consider the components available as well. There is no 12.65uf cap and it would be terrible expensive the have one made with that kind of tolerance if possible at all. Like all engineers they probably do the math then select the part with the closest value available with price considerations also being considered. All of this paragraph is guess work on my part. An engineer at Klipsch is the only one who could properly answer the question.

Just for the heck of it I measured some Dayton caps I bought many years ago when I was playing with crossovers with my Atlas Peak ESR+. I have a lot of them but only measured roughly 10 and found that most measured 0.00 with some of the larger ones with an ESR of just a few 0.01. This says nothing about how a capacitor will sound though. Testing ESR is just a tool used mainly for technicians to determine if a capacitor in a circuit has failed not on how it sounds if it is within tolerance. Also it is possible Carl just got a bad run, anything is possible but I doubt that it is the cause. Probably just a case of a capacitor an individual just does not care for how it sounds. I do not use Dayton caps for my crossovers or coupling caps in tube gear. Not my cup of tea. Work well for other means though when they are not in the signal path.

I just found a wonderful feature of this forum that enables you to ignore anyone that harasses you. Not that I have anyone that does so.

I am sorry for giving my opinion on your forum Medwin. I will refrain from doing so anymore because I do not like the way you treat people who disagree with you.

I believe that you believe all that you have said. Not what I would call mainstream audio design knowledge. You should start your own company selling the designs that are far superior than established principles. I have been in the electronic filed my entire life and my age is not far behind yours. I have no desire to get in a pi**sing contest with you. Like many legends in audio I believe the SE 300b amplifier is the ultimate in an active device. At least you have enough sense not to criticize the legendary Nelson Pass which is a devotee in designing simple circuits with few components. But then you and your two "hero's" that most have never heard of know better. The reason he builds SS amplifiers this way is because tube amplifiers built that way are considered the best sounding. My SE 45 tube amplifier is just one of many I own but one of my favorites. Trust me that I have many SE tube amplifiers that are just 2 stages along with many SS amplifiers with just 2 stages. I changed some features in my SE 45 tube amplifier design from the schematic and mine does not have an input transformer. The designer of said amplifier builds and sells transformers so naturally he puts as many in his designs as possible. https://www.electra-print.com/45silver.php He is known for his excellent transformers and not so much in his designs. I changed other things in the circuit as well. I would appreciate if you would not make your post personal. You have a right to have a difference of opinion but be a gentleman and keep your post civil and not get into personal attacks of someones electronic knowledge and hearing. You know absolutely nothing about me and my experience in the electronic field and I have no desire to brag on myself.

Really, not surprising. Don't worry be happy. 😀

I consider Nelson to be the premier amplifier designer for the last few decades if you mean hero. I have never heard of your hero's until you joined the forum. There are other designers I follow as well as him. He has stated many times his thing is SS but he does have tube amplifiers in his home he designed. Many consider his SIT-1 and SIT-2 as good as a SE 300b amplifier. I have not purchased one because I have a SE 300b amplifier and like tube gear but do play a lot with SS amplifiers. The market is SS these days so I blame no one for being successful for the market. You are confrontational with most on this forum who do not follow your advice of which I have no desire to do. I prefer SE tube amplifiers but not everyone has horn speakers and need more power for their speakers. That is the big reason the market is now SS and that and the younger audiophiles think transistors are better than tube being that they are a newer device. All this being said I do not think there will ever be a market of what you believe and design. Complicated designs with multiple components when fewer is better in my world. Some may like you philosophy and decide to build one of your circuits but it will not be me. When it comes to tube or SS amplifiers I am of the school of less components is better. More components do not add anything to the sound but may do the opposite.

Old McIntosh MC240 still much desired and pricey along with all their old tube gear. But then they are tube gear which SS amps have been try to mimic since invented. One thing that has changed in SS gear is at one time the designers were trying to best each other on spec's, lower distortion, more power, etc and now many are trying to make gear that sounds best instead. Measurements are just a tool and do not necessarily mean an amplifier will sound best. Many of the old SS gear will sound dry and sterile compared to the modern offerings. Just compare some of the descriptions by reviewers of new equipment vs the old reviewers who relied on specs more on how a piece of gear sound. Mosfets, which have curves like pentode tubes, are being used more in amplifiers in the newer offerings over BJT's as well.

This link may help. https://www.diyaudioandvideo.com/

I have 103db LaScala's and have played around with a full range open baffle speaker with 96db efficiency and only noticed a slight difference in output. I doubt there is a only a significant difference in volume until one gets below 90db. Firstwatt amplifiers are recommended for 90db and above speakers. Of course there always exceptions depending on multiple things, room, loudness one likes, etc. I have run test on power use at my house with volume so loud one cannot talk and found only a watt or two of average use with my speakers. I use to think more watts means better when I was younger but now know it is just a selling point to fool the consumer.

The 45 tube in a SE amp is considered by many as one that you can close your eyes and it is as though the singer is in the room with you but it is limited by a couple of watts. The sweet spot for me in an all around SE amplifier is 5 or 6 watts. Really nice bass and fantastic mids and highs. Naturally ones choice in music comes into play. If one likes hard rock and modern pop bass strong music a SE amp is probably not going to be a great choice for them especially if they like to shake walls. If you like to listen like when people were limited to just a radio and not television as more of background music they will be perfectly happy with less than a watt amplifier that Maynard loves so much. For what they do they do it fantastically. If a one watt amplifier is not good for horn speakers exactly what are they good for? Same for the popular SE 300B amps people shell out big bucks to buy that only have 5 or 6 watts. The EL34 family of tubes in SE are another good choice.

Nelson Pass has the same experiment in his listening room with full range speakers with less efficiency then horn speakers and the meters only reach 1 watt on peaks when the listeners say turn it down. Admittedly from my personal experience bass is better with more watts but that is not to say bass is not good with just a few watts. I have been listening this week with my SE 45 tube amplifier with only a couple of watts and enjoying it immensely using a sub with my LaScala's to round out the spectrum. Another reason could be that when a tube amplifier, with just a few watts, clips it is not unpleasant like when a SS amp does.

Congratulations. Enjoy

Just curious, did you have the same problem with the old crossovers? There are many they do not like the sonicaps that Bob uses. Never used them myself so no opinion. Caps used is a very subjective thing. This board has opinions all over the place. I will tell you what I like after much experimenting if you PM me. I do not want to go down the road of caps in an open setting. What you are describing as harsh may be considered as just too bright by many. L-pads are good at taming that problem. https://www.parts-express.com/speaker-l-pad-attenuator-50w-mono-3-8-shaft-16-ohm--260-254 The mid driver is considered a 16 ohm in a K-horn.

L-pads keep the impedance the same. They are nothing more than two resistors and will not significantly affect the sound any more than wire with some resistance. Some say you can hear a difference with monster cables instead of 18 gauge wire but I am not one of those. There are many excellent speakers that include adjustable L-pads with their speakers. Cost very little to try. I expect Klipsch has to use now use discrete L-pads in their crossovers since they abandoned the autotransformer. Discrete L-pads are the way you attenuate speakers or drivers where the have they same volume. Some do not like an adjustable L-pad but the pot that does it is in the real world very insignificant. You cannot change the taps on an AA network. Technically you can but it is a no no sonically. You need ALK crossovers to change taps. He uses a resistor in parallel with the autotransformer to enable changing taps.