MBL is a trademark. The image you showed is a logo. If I offer a drink for sale and call it Coca Cola or use the Coca Cola trademarked name to sell it, I don't need to have the red disk with stylized white lettering to be infringing their trademark.
This vendor is a thief and dishonest. I can't understand why you would defend that.
This vendor is a thief and dishonest. I can't understand why you would defend that.
Hello !
Can anyone confirm that there are no ad797 in the MBL 6010D but only ne5534 ?
I have 2 questions.
I understand that in the MBL the inputs are buffered before reaching the pot . As this is uncommon could it be one of the reason of great performance ?
Which pot and value is used in the MBL preamp ? I cannot understand from the pictures.
Thanks a lot
Kind regards,
gino
Can anyone confirm that there are no ad797 in the MBL 6010D but only ne5534 ?
I have 2 questions.
I understand that in the MBL the inputs are buffered before reaching the pot . As this is uncommon could it be one of the reason of great performance ?
Which pot and value is used in the MBL preamp ? I cannot understand from the pictures.
Thanks a lot
Kind regards,
gino
Since no one has responded to you, I'll offer an non-authoritative response.
. My take is that older versions of the 6010 utilized only NE5534s, while newer version utilize both the AD797 and NE5534. I don't know if that is true, and if true, which which version began including the AD797. Perhaps, someone who actually knows what they're talking about may yet respond.
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Since no one has responded to you, I'll offer an non-authoritative response.
I don't know if that is true, and if true, which which version began including the AD797.
Perhaps, someone who actually knows what they're talking about may yet respond.
Thank you very much indeed
I did not know of the two versions
Very interesting
Someone consider the 6010 one of the best solid state preamp around
Regards,
gino
Although I've not had the opportunity to audition a 6010D, it certainly does seem to have an excellent reputation. The question of whether or not it's the 'very best sounding' preamp isn't what intrigues me about it. What intrigues me about it is the fact that it features monolithic IC op-amps as the gain elements, yet still delivers subjective performance placing it AMONG the very best sounding preamps.
This appears true with certain other super high-end vendors as well, such as Burmester with their IC op-amp/discrete hybrid based 'X-AMP' topology, and AMR, and also with Swiss vendor Soulution. All offer very expensive gear, widely regarded as among the very best sounding money can buy, yet all reportedly utilize IC op-amps at their cores.
Not only do we in the DIY community seem to be in the dark about how to obtain top rank musicality from IC op-amps, but apparently, so are the many reasonably prices equipment vendors. I can only surmise that it comes down to certain implementation details, and not to some unique circuit topology, but I don't know. Clone schematics of the MBL 6010D (which, may not be accurate copies of the circuit) don't appear to show anything out of the ordinary. Obtaining first rate musicality from common IC op-amps certainly promises to simplify, and make less expensive, our DIY lives. Whatever is the trick, I wish I knew it.
This appears true with certain other super high-end vendors as well, such as Burmester with their IC op-amp/discrete hybrid based 'X-AMP' topology, and AMR, and also with Swiss vendor Soulution. All offer very expensive gear, widely regarded as among the very best sounding money can buy, yet all reportedly utilize IC op-amps at their cores.
Not only do we in the DIY community seem to be in the dark about how to obtain top rank musicality from IC op-amps, but apparently, so are the many reasonably prices equipment vendors. I can only surmise that it comes down to certain implementation details, and not to some unique circuit topology, but I don't know. Clone schematics of the MBL 6010D (which, may not be accurate copies of the circuit) don't appear to show anything out of the ordinary. Obtaining first rate musicality from common IC op-amps certainly promises to simplify, and make less expensive, our DIY lives. Whatever is the trick, I wish I knew it.
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I understand. Maybe the details are more decisive with op-amps than with discrete circuits ?
This is important from a DIYer point of view
Layout and component selection could be what makes a difference
It would be interesting to see some measurements on these clones anyway
I cannot imagine that in MBL they refine their products by ear
And then there is also a super pot i think
Thanks again
Kind regards,
gino
This is important from a DIYer point of view
Layout and component selection could be what makes a difference
It would be interesting to see some measurements on these clones anyway
I cannot imagine that in MBL they refine their products by ear
And then there is also a super pot i think
Thanks again
Kind regards,
gino
of course the Layout and component selection is important to get the best out of fairly fast low noise opamps. there are a few AD797 specific tricks as well to do with the pin 8 distortion reduction mechanism and its combination with and connection to the FB as far as layout this is critical. the ebay PCBs pictured dont have good layout, I prefer the soic8 package for layout its easier to get more effective HF decoupling, decoupling again in particular is pretty lame on these PCBs with the stock standard film caps too far away from the chip and too large to be all that useful.
luckily there is a raft of information online about how to get the most out of the AD797; on top of the extensive information available from AD themselves, Groner, Jung and Scott Wurcer himself on this forum to name a few. its not the easiest chip to apply but it rewards those who pay proper care.
luckily there is a raft of information online about how to get the most out of the AD797; on top of the extensive information available from AD themselves, Groner, Jung and Scott Wurcer himself on this forum to name a few. its not the easiest chip to apply but it rewards those who pay proper care.
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Thank you very much indeed
To be honest I played with some opamps, also the ad797, taking schematics from the datasheet and the pcb from a kits vendor.
Very bad results. Noise and so on ...
I would go for a populated evaluation board, but nowadys everything is smd
and so i am completely out of the game ...
But it is interesting to know that opamps have indeed a high potential for good sound
Thanks and kind regards,
gino
To be honest I played with some opamps, also the ad797, taking schematics from the datasheet and the pcb from a kits vendor.
Very bad results. Noise and so on ...
I would go for a populated evaluation board, but nowadys everything is smd
and so i am completely out of the game ...
But it is interesting to know that opamps have indeed a high potential for good sound
Thanks and kind regards,
gino
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Not to get off subject here but the word to note is not "identical" but the word next to it; the word "or". I'm also a Paralegal, and the issue is usually about the "or confusingly similar". This is a grey area that has quite a bit of latitude in the real world. Bottom line; if you're in the same industry, you better be unique pretty much across the board.
The AD797 is a great opamp, but so are many others. Understanding the limits of a given opamp and designing the peripheral circuitry accordingly is what makes a great sounding preamp. I use the OPA2134 dual opamps myself (same one Linkwitz uses in all his active crossovers and active EQ circuits). Use all metal film resistors for minimal hiss noise, and polypropylene caps for very low distortion ( the expensive one's, >$5 for a 1uF, are a scam). Ceramic caps are OK for power supply bypass.
Rather than buying a preamp kit, I'd recommend making a list of the functions you want your preamp to have, and then designing it that way. The web has tons of resources for learning anything you need to know. You can hand wire a vector board, or layout circuit boards with free layout software and have the boards made for you (expresspcb.com for example). I do both.
I happen to be building a preamp that I designed right now. It has an input selector switch, a X4 input buffer, a 4 section Baxandall tone control circuit, a bypassable dynamic range compressor, St. reverse switch, balance knob volume knob, regulated power supplies, turn-on time mute circuit with sealed gold contact relays so no turn on transients. Doing grounding right (star center), and having approx. 0.1uF powersupply bypass caps within an inch of every opamp is key. Opamps want to see zero ohms when they look at the power supply from DC to infra-red. Otherwise their phase margin is less predictable. That can cause oscillation, which can be quite catastrophic. A wire an inch long looks like an inductor at 10mHZ . Hence the need for the bypass or decoupling caps.
Back in 1970-ish when I built my first hi-fi preamp from a kit, it oscillated at a frequency I couldn't hear (above 20kHZ). I had nothing but a voltmeter in those days, no scope or even test generator. After about 10 seconds, the poweramp blew up and it blew the 4 inch test speaker so bad that when I pulled the voice coil out of the 4 inch speaker, there was a thermally treated paper bobbin with no coil of wire on it at all. The entire coil disintegrated. The poweramp was a SWTPC Universal Tiger measuring about 130 watts rms before it blew. Many poweramps have a hard time handling super sonic oscillation. If the poweramp doesn't blow, the tweeters are likely to burn out. Even spurious oscillations are to be avoided at all costs. Running a 10kHZ square wave through a preamp will give some idea of its tendency to oscillate, if viewed on an oscilloscope. Look for overshoot and ringing. It should be a very small percentage. The scope should have a bandwidth of at least 100mHZ. Also observe whether or not it clips cleanly on both half cycles.
Rather than buying a preamp kit, I'd recommend making a list of the functions you want your preamp to have, and then designing it that way. The web has tons of resources for learning anything you need to know. You can hand wire a vector board, or layout circuit boards with free layout software and have the boards made for you (expresspcb.com for example). I do both.
I happen to be building a preamp that I designed right now. It has an input selector switch, a X4 input buffer, a 4 section Baxandall tone control circuit, a bypassable dynamic range compressor, St. reverse switch, balance knob volume knob, regulated power supplies, turn-on time mute circuit with sealed gold contact relays so no turn on transients. Doing grounding right (star center), and having approx. 0.1uF powersupply bypass caps within an inch of every opamp is key. Opamps want to see zero ohms when they look at the power supply from DC to infra-red. Otherwise their phase margin is less predictable. That can cause oscillation, which can be quite catastrophic. A wire an inch long looks like an inductor at 10mHZ . Hence the need for the bypass or decoupling caps.
Back in 1970-ish when I built my first hi-fi preamp from a kit, it oscillated at a frequency I couldn't hear (above 20kHZ). I had nothing but a voltmeter in those days, no scope or even test generator. After about 10 seconds, the poweramp blew up and it blew the 4 inch test speaker so bad that when I pulled the voice coil out of the 4 inch speaker, there was a thermally treated paper bobbin with no coil of wire on it at all. The entire coil disintegrated. The poweramp was a SWTPC Universal Tiger measuring about 130 watts rms before it blew. Many poweramps have a hard time handling super sonic oscillation. If the poweramp doesn't blow, the tweeters are likely to burn out. Even spurious oscillations are to be avoided at all costs. Running a 10kHZ square wave through a preamp will give some idea of its tendency to oscillate, if viewed on an oscilloscope. Look for overshoot and ringing. It should be a very small percentage. The scope should have a bandwidth of at least 100mHZ. Also observe whether or not it clips cleanly on both half cycles.
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Afaik, there is no IP issue with posting images of a unit that you have taken pictures of. No matter what the resolution or detail.
Copying the actual unit or circuit for commercial sale is another matter.
Afaik, reverse engineering the circuit and posting it is not an infringement of IP. It's fair use, imo.
I am not an attorney, nor do I play one on TV.
Copying the actual unit or circuit for commercial sale is another matter.
Afaik, reverse engineering the circuit and posting it is not an infringement of IP. It's fair use, imo.
I am not an attorney, nor do I play one on TV.
That's also my understanding. Tracing out a circuit and selling your own version for commercial use is also legal as long as there's no patent or trade dress infringement. Copying a layout and using someone else's trademark to sell a knock-off is a different story, and should be a warning that you're dealing with someone dishonest.
Same disclaimer: IANAL.
My understanding is that reverse engineering a circuit and posting it may be a copyright infringement in Europe. There is a specific permission for reverse engineering for the purpose of making a different product which has to interface to the first one. There is also specific permission for the purpose of private study, which probably includes professional teachers and their students but perhaps not a DIY forum.
There is a permission for making public a small extract of the 'work' for the purpose of comment or criticism. I take this to mean that I can exhibit a small part of a circuit in order to say something like "their cathode follower is badly designed" or "that is a really clever idea".
In practice, as always, it is up to the copyright holder to police their own copyright so minor infringements (especially if for non-commercial purposes) are likely to be ignored except by certain bullies who seem to take pride in sending rude lawyer's letters to small businesses.
Having seen a book I edited on a pirate website I am generally on the side of copyright holders!
There is a permission for making public a small extract of the 'work' for the purpose of comment or criticism. I take this to mean that I can exhibit a small part of a circuit in order to say something like "their cathode follower is badly designed" or "that is a really clever idea".
In practice, as always, it is up to the copyright holder to police their own copyright so minor infringements (especially if for non-commercial purposes) are likely to be ignored except by certain bullies who seem to take pride in sending rude lawyer's letters to small businesses.
Having seen a book I edited on a pirate website I am generally on the side of copyright holders!
Hi, taken from the Onsemi datasheet ...
I read some audiomagazines and the MBL 6010D preamp has been really highly praised, one of the best line stage around they say.
Measurements are impressive ... almost no noise of distortion to speak of.
I wonder if the buffering of inputs is key to this performance.
Thanks and regards,
gino
You can usually purchase a full teardown of the latest Intel processor a few months after release. In the US this common practice and perfectly OK, I have ordered teardowns from a service (~20K for 100 transistor chip).
Masks are protected as maskwork and it is illegal to photographically copy an exact chip's masks and fabricate them just as it is probably not legal to copy an exact PC layout that they have taken the effort to copyright.
There is a very nice paper that is written by lawyers from UC Berkeley on the whole issue of reverse engineering. In the end, at least here, patents are your only real protection of your circuit ideas.