thanks for all inputs.
-I do understand differnce from pre amp and Volumpot and source selection.
-To say that I don`t kneed a preamp is in a practical way correct. However I am knot a beliver in less is more. I want preamp with tubes. not because of gain but the life it has given my system.
-After some thought i come to the conclusion that I will build a Aikido (zero gain) buffer stage followed by a NEUROCHROME UNIVERSAL BUFFER. I vill give a tube buffer a try. If it dosent work its not the end of the world it will cost me around 450 dollars.
-I do understand differnce from pre amp and Volumpot and source selection.
-To say that I don`t kneed a preamp is in a practical way correct. However I am knot a beliver in less is more. I want preamp with tubes. not because of gain but the life it has given my system.
-After some thought i come to the conclusion that I will build a Aikido (zero gain) buffer stage followed by a NEUROCHROME UNIVERSAL BUFFER. I vill give a tube buffer a try. If it dosent work its not the end of the world it will cost me around 450 dollars.
Still you found out that no/less gain = more! 😀
Pleae: a preamp is an amplifying device, a buffer is a device that amplifies 0.99x and we tend to shorten that to 1x. Standard 2Vrms in means 2Vrms out with buffers at max. volume. Therefor slight gain may be wished when the power amplifier is not sensitive enough aka audiophile stuff with odd parameters.
Both devices are buffers (so both without gain and/or GAIN) and not preamps so you will, in fact, not "enhance" your setup with a preamp. One of the standard virtues of buffers is high input impedance and low output impedance. The latter is nice when driving solid state amplifiers with let's say 30 kOhm input impedance. One of course needs to make sure to use the right value output cap for the buffer to avoid loss of bass....
Pleae: a preamp is an amplifying device, a buffer is a device that amplifies 0.99x and we tend to shorten that to 1x. Standard 2Vrms in means 2Vrms out with buffers at max. volume. Therefor slight gain may be wished when the power amplifier is not sensitive enough aka audiophile stuff with odd parameters.
Both devices are buffers (so both without gain and/or GAIN) and not preamps so you will, in fact, not "enhance" your setup with a preamp. One of the standard virtues of buffers is high input impedance and low output impedance. The latter is nice when driving solid state amplifiers with let's say 30 kOhm input impedance. One of course needs to make sure to use the right value output cap for the buffer to avoid loss of bass....
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how do manufactures get this right? like ps audio they have dac-pre-poweramp all with gain I presume.
They design the power amplifiers with right value volume control and source selection and call it integrated amplifiers. In the tiny solid state world there do exist standards and when designing separates they do this to standardized signal and impedance levels so things just work OK together.
So 95%+ of solid state buffers/preamps go together well with 95%+ of solid state power amplifiers. Both go well together with 95%+ of standardized solid state sources. This means one can almost bring a random DAC/streamer over to a friend and it will work well with the random preamp/buffer/integrated amplifier he has. The tube world will have a meeting about this subject somewhere in 2030 I heard.
So 95%+ of solid state buffers/preamps go together well with 95%+ of solid state power amplifiers. Both go well together with 95%+ of standardized solid state sources. This means one can almost bring a random DAC/streamer over to a friend and it will work well with the random preamp/buffer/integrated amplifier he has. The tube world will have a meeting about this subject somewhere in 2030 I heard.
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The 6AS7 as a buffer will give a gain of about 0.6... Not all tubes make good followers 🙂 Yes, SS 1x buffer (unity) is easy - just get an opamp. 😀
Typically, a 6DJ8 or 6SN7/6CG7 make a decent buffer. I also use 6N3, 6N1, 6N5, 6N6, 6N14, 6N23, 6N24 and have boards for them all in stock if you want an easy cheap solution.
I'm not part of the typical "tube" world - my stuff has to work with modern electronics if I'm going to offer any of it for sale. All will work as Jean-Paul describes - The Zin is whatever you like (stand alone buffer default Zin = 333k), the Zout is between 50R and 1k depending on the tube you use for a buffer.
Typically, a 6DJ8 or 6SN7/6CG7 make a decent buffer. I also use 6N3, 6N1, 6N5, 6N6, 6N14, 6N23, 6N24 and have boards for them all in stock if you want an easy cheap solution.
I'm not part of the typical "tube" world - my stuff has to work with modern electronics if I'm going to offer any of it for sale. All will work as Jean-Paul describes - The Zin is whatever you like (stand alone buffer default Zin = 333k), the Zout is between 50R and 1k depending on the tube you use for a buffer.
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I only know the standards and buffers are 0.99x by default. Tubes that make that different are better not used I would say.
...... an opamp.........OMG! BTW the least negative setting to use opamps is in unity gain mode indeed.
...... an opamp.........OMG! BTW the least negative setting to use opamps is in unity gain mode indeed.
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The 6AS7 has a mu of only 2, but it has only 300R internal resistance. It was designed as a pass tube.
Most tubes will be 0.95 or higher though, but if you need to drive a VERY long cable, or you want to drive 32R headphones without matching transformers, then the 6AS7 and it's 0.6 ish gain is acceptable, just put voltage gain in front of it 🙂
Most tubes will be 0.95 or higher though, but if you need to drive a VERY long cable, or you want to drive 32R headphones without matching transformers, then the 6AS7 and it's 0.6 ish gain is acceptable, just put voltage gain in front of it 🙂
Ahem, that is one gain stage too much and it then is not a buffer anymore. Please tell the OP as tube guys only take advice from tube guys 🙂 to use a minimum output capacitor of 4.7 µF or even a 10 µF one (right voltage ratings please) and a relay muting circuit to avoid severe shock by the power amplifier and the speakers. If the power amplifier is a true power amplifier without volume OP will enjoy "tube magic" when switching on the buffer after the power amp is switched on otherwise. For a few $ this is solved elegantly.
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12V TVS bidirectional diode is much cheaper than a delay relay circuit, and I've never blown up any amplifier I've ever connected to any of these even without one. Sure, you get a thump, but so what? LOL
And yes, I design them to use a 10uF polypropylene cap (or a large electro in the case of headphones) for output.
And yes, I design them to use a 10uF polypropylene cap (or a large electro in the case of headphones) for output.
1. OP has a Paramount A21 which is very solid state and solid state stuff should be protected against evil tube voltages that come up during power on...and power off
2. Non linear semis in tube stuff versus a small cheap circuit that is not in the signal path....
3. If it is not the Paramount dying then the speakers will protest which is completely unnecessary when adding a small few $ circuit way cheaper than the speakers cost...
4. User friendliness is a factor liked by many... a small few $ circuit will cause 100% silent startup and power down in any possible sequence also by less technical family members...
5. The paramount has a muting/speaker relay. Many audio guys like the 100% silence and the sophisticated click of a relay and feel this to be class/style... non reason but still 😉
5. Cheap is the enemy of good.
When I worked at a Japanese audio company somewhere in the eighties all their mid range devices already had muting relays. Maybe something to also discuss in 2030 🙂
2. Non linear semis in tube stuff versus a small cheap circuit that is not in the signal path....
3. If it is not the Paramount dying then the speakers will protest which is completely unnecessary when adding a small few $ circuit way cheaper than the speakers cost...
4. User friendliness is a factor liked by many... a small few $ circuit will cause 100% silent startup and power down in any possible sequence also by less technical family members...
5. The paramount has a muting/speaker relay. Many audio guys like the 100% silence and the sophisticated click of a relay and feel this to be class/style... non reason but still 😉
5. Cheap is the enemy of good.
When I worked at a Japanese audio company somewhere in the eighties all their mid range devices already had muting relays. Maybe something to also discuss in 2030 🙂
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Cheap is the enemy of audiophoolery, and any good SS design has those protections built into it. If I can turn on the preamp with a 1200W yorkville turned on and not even see a speaker wiggle, I see no reason to add extra parts and complexity to solve a non existent problem. Even then, a 50 cent TVS diode will do the same job as a 10$ relay delay (protect the downstream parts from excessive voltage), so why waste money? And before you say "parasitic capacitance that varies with the voltage", a few picofarads on the output of a buffer with a Zout of <1k is hardly any cause for concern IMHO.
If you want "user friendliness" then go to Best Buy and buy a Yamaha. This is DIY audio. We do things the hard way for fun, right? 😀😀😀
If you want "user friendliness" then go to Best Buy and buy a Yamaha. This is DIY audio. We do things the hard way for fun, right? 😀😀😀
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No you are wrong. In more than one aspect as indicated in post #50. In a solid state world not many amplifiers are protected against possible high DC voltages at inputs. They are protected against their own errors and power on/off clicks as a standard. Since the tube device is the odd device causing a risk it is the device that should be prevented to cause damage to other gear. At least that is how I got stuff taught. There is also no reason to make stuff mediocre or less user friendly. Stuff can be made mediocre but most will prefer a certain look and feel.
Of course Parasound got their stuff right:
Total Protection - Relays
Each channel of the A 21+ has a high-quality protection relay with gold-plated contacts for long-term reliability. These relays function to protect either the amplifier, the speakers, or both. When the A 21+ is first powered on, these relays remain open for approximately three seconds as the positive and negative power supplies stabilize and reach equilibrium with no DC offset at the speaker terminals. This prevents annoying popping or other transient noises. Relay protection also prevents damage to your speakers in case of a catastrophic amplifier failure. Any amplifier that doesn’t use relay protection for its speaker outputs compromises the safety of the amplifier and your speakers.
Too bad they made an error by using gold plated contact relays for speakers but we can predict what the most common error will be in a few years from now. BTW Did you ever find the design errors in the PCB design in the other thread?
Of course Parasound got their stuff right:
Total Protection - Relays
Each channel of the A 21+ has a high-quality protection relay with gold-plated contacts for long-term reliability. These relays function to protect either the amplifier, the speakers, or both. When the A 21+ is first powered on, these relays remain open for approximately three seconds as the positive and negative power supplies stabilize and reach equilibrium with no DC offset at the speaker terminals. This prevents annoying popping or other transient noises. Relay protection also prevents damage to your speakers in case of a catastrophic amplifier failure. Any amplifier that doesn’t use relay protection for its speaker outputs compromises the safety of the amplifier and your speakers.
Too bad they made an error by using gold plated contact relays for speakers but we can predict what the most common error will be in a few years from now. BTW Did you ever find the design errors in the PCB design in the other thread?
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"Any amplifier that doesn’t use relay protection for its speaker outputs compromises the safety of the amplifier and your speakers."
Except when using transformer coupling, eh?
Except when using transformer coupling, eh?
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I guess quite a few possible future problems as most relays are a waste of time for protecting speakers unless used in low power amps because they usually can not break the arc to an inductive load like most speakers And the answer these days on DIYaudio is to use a solid state relay made from a pair of mosfets and optodriver chip.
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The real reason no protection is really needed in the aikido style buffer is that there is no turn on thump because the tubes need to warm up and start conducting. The voltage at the capacitor slowly rises from 0V to 1/2 B+ rather than starting abruptly at B+ and dropping to 1/2 B+.
As I said, if a protection delay shorting relay was necessary, I'd use one.
As I said, if a protection delay shorting relay was necessary, I'd use one.
Why people in this section have so much trouble using standard protection as used elsewhere in abundance I don't know. In all quality sources muting relays are used....
I have repaired devices that were damaged because of thrown together inserted tube devices that produced "blacker than blacks" and developed slowly ramping up DC voltage through the output cap. Well, that was true as it indeed stayed blacker than black after a while 🙂 If someone has upper class solid state gear following the 5$ cost max. makes things certain and protected in all scenarios. It is a question of limiting risks and designing devices to be interchangeable in different scenarios. That relays are a waste of time is a sheer lie. I repair audio for decades and have seen quite some damage also by reputable brands that omitted protection. I can tell unlikely scenarios what went wrong but it always ended up with expensive repairs.
Maybe the naysayers should check their sources ands how things are done there. Even diyaudio.com devices like Mezmerize have muting. So it won't surprise me a bit that those sources you own and use all have muting in one form or another. One knows this when repairing/designing source devices. It is not me but YOU against the world.
I have repaired devices that were damaged because of thrown together inserted tube devices that produced "blacker than blacks" and developed slowly ramping up DC voltage through the output cap. Well, that was true as it indeed stayed blacker than black after a while 🙂 If someone has upper class solid state gear following the 5$ cost max. makes things certain and protected in all scenarios. It is a question of limiting risks and designing devices to be interchangeable in different scenarios. That relays are a waste of time is a sheer lie. I repair audio for decades and have seen quite some damage also by reputable brands that omitted protection. I can tell unlikely scenarios what went wrong but it always ended up with expensive repairs.
Maybe the naysayers should check their sources ands how things are done there. Even diyaudio.com devices like Mezmerize have muting. So it won't surprise me a bit that those sources you own and use all have muting in one form or another. One knows this when repairing/designing source devices. It is not me but YOU against the world.
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I've never seen a muting relay in a source in my entire life. I do know if I send a spike through my SS power amplifier, it will mute itself - the protection is and should be built into the amplifier IMHO.
It's diY audio...Want a muting relay? Make it yourself and add it. I even made a PCB on another thread for a muting circuit and gave the Gerber for free.
It's diY audio...Want a muting relay? Make it yourself and add it. I even made a PCB on another thread for a muting circuit and gave the Gerber for free.
Maybe you are very young or you don't look in quality digital source devices. I worked as a tech for an audio company and I have modded literally hundreds of CD players, DACs etc of all price ranges. The quality determines how muting is done. Any digital source device has muting transistors/FETs or built in in IC's and the better ones have transistors/FETs (for digital errors) and relays for power on/off protection. The device that is the risk needs to be equipped with protection to protect other devices. That is standard design practice at many brands but tube people probably know better.
It is not that I want it, I just recommend OP to do something to protect the Parasound A21 in all possible scenarios that may occur with a superfluous device that is not even needed. Sane people protect their stuff. A Parasound Halo A21 costs 3899 Euro but you would send a spike through it, yeah right. Even the 175 Euro tube hybrid preamp right in front of me mutes outputs at power on for 30 seconds. With a relay.
Mezmerize B1 Buffer – diyAudio Store
Spot the relay in the Topping D30:
It is not that I want it, I just recommend OP to do something to protect the Parasound A21 in all possible scenarios that may occur with a superfluous device that is not even needed. Sane people protect their stuff. A Parasound Halo A21 costs 3899 Euro but you would send a spike through it, yeah right. Even the 175 Euro tube hybrid preamp right in front of me mutes outputs at power on for 30 seconds. With a relay.
Mezmerize B1 Buffer – diyAudio Store
Spot the relay in the Topping D30:
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And being as I design everything to be modular, you want relay muting? Add the module. Input switching? Add the module. Phono? Add the module. VU meters? Add the module. Do It Yourself! That's what this site is about.
I'm from the design school that says whatever the device is, it should withstand all surges and spikes, and not rely on the downstream connected equipment to do so...
If I plug a 120V device into 240V and anything more than a fuse blows, I consider the design to crap. Sh*t happens.
And IMHO, a 3899€ amplifier should be designed to accept a lightning strike on it's input and live to play audio. Just my opinion. A TVS diode is 50 cents... That said, I'd never pay 3899€ for a power amplifier. I make good sounding tube stuff without the ridiculous price tag.
Here's a shot of a modular preamp I'm building for a client. Actively loaded gain/buffer, buffer, transformer coupled output, phono, vu meters, janus regulator, bluetooth, etc.
I'm from the design school that says whatever the device is, it should withstand all surges and spikes, and not rely on the downstream connected equipment to do so...
If I plug a 120V device into 240V and anything more than a fuse blows, I consider the design to crap. Sh*t happens.
And IMHO, a 3899€ amplifier should be designed to accept a lightning strike on it's input and live to play audio. Just my opinion. A TVS diode is 50 cents... That said, I'd never pay 3899€ for a power amplifier. I make good sounding tube stuff without the ridiculous price tag.
Here's a shot of a modular preamp I'm building for a client. Actively loaded gain/buffer, buffer, transformer coupled output, phono, vu meters, janus regulator, bluetooth, etc.
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one of the things that I like about tube equipment is that it’s robust, not sensitive to static, runs hot anyhow, accepts variations in mains voltages. I tend to stick with cathode self-bias too.
ss stuff has to be protected but I’ve not bothered to protect from output shorts. Seems too much trouble to do it properly so I’ll let the output devices be the fuse.
ss stuff has to be protected but I’ve not bothered to protect from output shorts. Seems too much trouble to do it properly so I’ll let the output devices be the fuse.