Why would I desire a built in, and limiting, pre?
By the way, don't see me buying new, to get anything decent costs way more than I can spend. Look at the statistics on say the Technics SL-1500 or SL-1700, or even a better example, Technics SL-10 or SL-15, linear tracking is going to cost far, far, more buying new.
I understand this, was asking if a classic because it is a great or fantastic typology.
Why is it used a lot if not a satisfactory performer?
Did a good bit of research, the ECC83/12AX7 can be replaced, tube rolled, with 12AT7 and a few others. I am grateful you mentioned this, learned a lot. 😀
By the more I read about the 12AT7, the more I understand why preferred over the 12AX7.
Thank you for the links, appreciated. 😀
Interestingly, this claims the 12AT7 is superior to the 12AX7 as a phase splitter.
So this latest is a DC LTP and the L1 clone is a cathodyne?
Neat!
So now sensing good have not pulled the trigger on an oscilloscope, as now my ponderance, especially as the separate sound card device costs the same, if the virtual oscilloscope be better. Do you have any opinion, please?
Per chance generate a square wave to adjust the feedback loop?
Appreciate knowing this, thank you. 🙂
By the way, gave up on CDs, only have a few and sometime replace a couple with LPs.
Yes, thank you. 🙂 Some reason not understanding all of it, probably because it is words and not objects.
What do you mean condition the amplifier signal? No, I didn't see it...
What is a dummy load versus the 8Ω resistor? I wasn't finding the answer in that thread...
You ever feel your folks are still communicating with you even after they have deceased? I do, here is an example. When Dad passed fairly unexpectedly at age 72 (his family lives well into their 80s, if not well into their 90s) June 2019 (feels very recent) I inherited a lot of books, a lot. This evening, going through some and find this book. Neat!
What is puzzling is Dad never built anything, used a transistor radio to listen to short wave, his Dad helped put a wire loop antenna on the roof. He has read it, made a correction to the text (also interesting as he never wrote in his books, part of his almost obsessive desire to keep them nice). One of many questions wish could ask him. So now really motivates me to build, another shared interest.
By the way, when Dad get a new hard bound book, he never fully opened all at once, he gently open both covers one at a time, softly rub the inside binding crease, then repeat for about ten pages back and forth before getting to the center, so as not to split the binding.
What is puzzling is Dad never built anything, used a transistor radio to listen to short wave, his Dad helped put a wire loop antenna on the roof. He has read it, made a correction to the text (also interesting as he never wrote in his books, part of his almost obsessive desire to keep them nice). One of many questions wish could ask him. So now really motivates me to build, another shared interest.
By the way, when Dad get a new hard bound book, he never fully opened all at once, he gently open both covers one at a time, softly rub the inside binding crease, then repeat for about ten pages back and forth before getting to the center, so as not to split the binding.
Another great reference.
https://ia802208.us.archive.org/7/i...sic Electronics, Volumes 1-5, (1955)_text.pdf
https://ia802208.us.archive.org/7/i...sic Electronics, Volumes 1-5, (1955)_text.pdf
It is 🙂 I don't use them though - no other tube is a compromise between two versions of crap IMHO (I find the 12A*7 family to be "good enough" but barely...).
I could be wrong though, but the curves of the 12AT7 aren't what I'm looking for.
The 6F12P is essentially 10 12AX7 in parallel, but without 10x the Cin (input capacitance). Apparently, you CAN have your cake and eat it, too 😀
Start with an affordable good enough scope?
http://www.hantek.com/products/detail/31
A 100X probe might be handy though... I use this: https://www.amazon.com/gp/product/B07F65SZMV/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
https://www.ebay.ca/itm/253778042791
I don't buy them anymore, either. Vinyl all the way.
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Thank you! 😀 At this rate of generosity, going to take me a couple of months to read all the books.😛
Missed you as been trying to find out if any difference in sound of cathodyne versus LTP. Not much out there, what there is seems to show a preference for LTP.
Does have good reviews on Amazon.
Once less piece of equipment to purchase and have taking up space. 🙂
Well, there is also 6SL7 and 6CG7 which can be tube rolled into a 12A*7 family.
Intersting tube! Though my limited knowledge seems to suggest not a substitute for the 12A*7 family without modifying the circuit, correct?
Well, this is sure interesting, especially the price. 😀 To confirm, work just as well adjusting the feedback loop and other tasks related to amplifier build as a professional unit?
Does have good reviews on Amazon.
What is its purpose?
Neat.
Once less piece of equipment to purchase and have taking up space. 🙂
Hey José (@jcalvarez ) now that read more of the thread, see the Behringer (https://smile.amazon.com/BEHRINGER-Audio-Interface-1-Channel-UM2/dp/B00EK1OTZC?th=1) is also an option, significantly less cost. Hmmm... 🤔
Forgot to respond...
Something in the refrigerator had shorted. Should share ground with the common/negative wire (which should be grounded at the fuse box).
This is why those three to two prong adapters must be grounded! Without the ground, if a short happens, the enclosure becomes charged.
I grew up in a track house built in 1942 or 1943, for the influx of Navy men. Had two or three additions over the years, though the service remained two fuse panels (one added in a laundry during the first addition). Don't know how many amps, not enough as when either the regrigerator or the gas drier come on, the lights in several rooms turn off and on. Plus, there was one or two plugs per a room, except the last addition which was a spacious front room had four, one each wall. Plethora of extension cords used, a bit of a wonder how nothing went wrong. Honestly, think the electric code has swung the other way having outlets every 12 feet. Here in the rental, there are outlets behind doors, so if for a vacuum have to shut the door, on walls too short to put furniture against. Myself, only use one, maybe two, the hifi system is plugged into a surge protector (so can turn off when hear thunder).
I feel like that's similar to how many people who smoked when I grew up smoked Du Maurier cigarettes or bought a Honda. They aren't anything to write home about to their friends had one/smoked them.
Technically, you can get better balance with an LTP, but for me, if you have a properly spec'd "cathodyne" (I call it a split load phase splitter), the difference is lie kspit in the ocean IMHO.
There is, but There's also 6N1P and 6N2P (6N3, 6N14, 6N24)and they are all great cheap alternatives to expensive Western tubes.
Correct. If you look at the Modular Amp or the Little Miracle, you can see how I use it.
If I had to guess, I'd say you'd need to roughly double the cathode resistor values to use in instead AKA 68R becomes 150R, and 330R becomes 680R. - just in my VA/PI design though.
That's the scope I use to design and build with... It's not a tektronix, but you aren't working on a bloody space probe, either. It's more than good enough for audio IMHO.
It allows you to measure higher voltages with the scope before either running out of headroom or blowing it up...
I mean CD's take up less physical room than records, but I don't miss buying CD's. I have a good player to play (or record) other people's CD's 🙂
As far as physical media, I still love Minidisc. It was suppoed to be a replacement for tape. Fast forward almost 30 years and the MicroSD card can't really be beat. They can fit 1.5 terabytes of data on something the size of a fingernail!
My dad worked with mainframes in his career and spoke about a "Teradata machine". It was the name of the company but it stored a terabyte at the time. It wouldn't fit in my apartment, but it stored it! Now, you can put 20TB in your pocket!
Can't sleep, so might as well get something done. 😛
Western tubes being the 6SL7 and 6CG7?
Now hit me, bet not one mainframe left, just maybe in a museum.
Interesting these were not mentioned.
Western tubes being the 6SL7 and 6CG7?
This for me doesn't count as tube rolling, as the circuit has to be modified, leading to the possibility the specifications/sound is degraded, especially a beginner like me. However, do appreciate the knowledge and a bit surprised as simple as doubling the resistors in the LTP.
Just checking as seems unbelievable $68USD + ~ $20USD for the 100x probe gets you an oscilloscope that is sufficient even for someone very advanced. Bonus is can capture the screen allowing to share on the forum.
Exactly. I just been looking casually for something sufficient.
Found this later and forgot to say so. If understanding correctly, takes the 5 volt limit and multiplies by 100, for 500 volts maximum.
LPs, unlike CDs, can be leaned against walls and furniture, unlike CDs. 😛 (Kind of being silly, at your own peril, of course.) Myself find CDs harder to store, mostly because slippery.
Lost both my flash drives in the forced move (family stole my house) and was pleasantly shocked how much the price of flash drives have dropped. Something seemed odd about the picture, only when I got it did realize they have become super tiny. I can barely remember 5 1/2 inch floppy disks, I grew up with 3 1/4 inch disks (used also in a Sony digital camera with a whopping 3 megapixels IIRC), find it amazing how far storage has come in my lifetime.
Now hit me, bet not one mainframe left, just maybe in a museum.
Yes. Soviet equivalent to 6SL7 is 6N9S. 6CG7 is a 6SN7 in a 9 pin B9A based tube - 6N8S is the Soviet 6SN7. (Soviet != Russian, you can buy Soviet tubes from Ukraine)
Easy way to think of it? Take a typical circuit using 6DJ8. Ra=10k, Rk=200R... Parallel both halves but keep the same operating voltages? Now Ra=5k, and Rk=100R.
It's plenty for audio. A scope with a 500kHz bandwidth can be used to fix an NTSC television.
Correct!
I find it opposite - a CD can be a frisbee and still sound the same... Not so with a record 🙂
And if the record is old enough, it'll break like plate glass if you drop it... Before vinyl, they used shellac or pressed rubber.
It's really remarkable 🙂
Now, the only 3½" floppy disc I've using stops my dresser from wobbling... Like putting a coaster under the wobbly table on a patio 🙂
That 8ohm resistor is the dummy load.
Yes, it can, also other shapes:
In my opinion the best option is a good Tektronix oscilloscope. But that is very costly and difficult to justify. The sound card+REW is the cheapest option, and probable the best compromise and value option is the Hantek oscilloscope adapter that Koda showed you. I got lucky and was gifted a Tektronix TDS-1012B. It is around 15 years old but runs like a swiss clock.
There is nothing wrong with the topology. Performance is related to a design. Which one do you mean that has no satisfactory performance?
Also, if you ask around, there are people who will tell you that a particular topology is the best and everything else is rubbish. You can find discussions around the net about triode vs pentode, single ended vs push-pull, tubes vs solid state etc etc. Some of those discussions go for years and resemble a mini-war 🙂
Yes, the L1 clone is a cathodyne, DC coupled. Not sure which one you mean by "latest", sorry.
By conditioning I meant making sure the sound card input can handle the measured signal. A 10W amplifier output signal, assuming an 8ohm load, will be ~9V RMS. That will probably fry the sound card input, therefore they use a resistor divider (typically 10:1) to reduce the output signal to a value that the sound card can safely handle. I have marked it in the picture below. You can see the white and brown wires going from the dummy load 8ohm resistor (basically the amplifier output) to a simple voltage divider, just a couple of resistors, 20K:2K, giving an approximate 10:1 voltage reduction.
Tubes tend to have a certain type of distortion that can sound very euphonic on fairly simple music. OTOH more complex music can get overly congested with IMD. In either case its not as close to sounding like being in a real concert hall, say, in the 5th or 6th row, as compared to what is possible with the best of SS. In that context the term 'best of SS' should be taken to mean best sounding, not necessarily best measuring.
Also regarding FFT measurements, I would suggest to be wary of looking at FFTs too early in the design process. Looking at them creates a bias to want tweak the design to make the FFT to look nice, possibly at the expense of ignoring things about sound that are not as easily measured with a sound card. Also, looking at FFTs tends to bias people's expectations about what an amplifier will sound like. There is an expression to the effect that, "you need to listen with your ears, not your eyes." To me that includes looking at FFTs before listening. However, listening well is a skill that takes time and practice to do skillfully. People who have not developed skill tend to think almost any difference they hear after a change to the design is a change for the better. Often in reality the change is just different or maybe even worse. That may not realized until the change has been listened to for long enough period of time to get over the initial bias.
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I think one of the few of my generation who knows what USSR stood for.
I was thinking meaning Western Electric...
Or in the last schematic, R7 68kΩ becomes a total of 136kΩ going to pins 3 and 8, if understanding correctly.
Okay, thank you for clarifying and additional information.
So the pickups vary in ability? The unit that quit seeing the disk any minor scratch be picked up, if more than, it get stuck and repeat itself over and over.
I was being mostly silly, did say fraught with risk. Though since as of yet don't own any 78 records, didn't cross my mind, know they are delicate (made from crushed beetle exoskeletons).
I never heard of pressed rubber, I am surprised have not turned into dust.
Neat! 🙂
Also see does other sounds too.
Do you have a preference of one over the other?
The typology being discussed, deployed in the Elektor Electronics deploys.
I have realized this. Additionally, seems one should build something, then if satisfied, then that can be it.
Myself, feel should take @Markw4 's advice and do some reading, which I am, and seeing its benefit, which encourages me to keep reading.
The Elektor Electronics amplifier.
I really appreciate the summation and clarity, thank you; now it makes since. 🙂
The colon means in parallel?