Chaps,
Chaps,
Too many moons ago, around 1965, I had a Marantz 7 preamp, it sounded great in a system of that era.
However, how does it sound by today's standards, can you justify the high prices in comparison with Electron Images, Shindo, Audio Note, VAC, CAT, Art Audio ...?
Cheers,
Horacio
Chaps,
Too many moons ago, around 1965, I had a Marantz 7 preamp, it sounded great in a system of that era.
However, how does it sound by today's standards, can you justify the high prices in comparison with Electron Images, Shindo, Audio Note, VAC, CAT, Art Audio ...?
Cheers,
Horacio
Marantz 7C
The Marantz 7C and McIntosh C22 are in my opinion totally over rated preamplifiers.
Firstly their RIAA sections are both AC coupled from 1st to 2nd tubes.
Secondly their EQ is active and driven by poorly designed cathode followers.
Thirdly the choice of tubes (ECC83) is certianly not the best.
Fourth the quality of the rotary switches is not good at all.
The power supplies are wimpy and not well designed but in that era this was par for the course.
Of course in their defense the available parts in the 50's and 60's was quite poor compared to what we have today.
We have restored many of these with great results.
Replace every single passive part.
Hard wire the RIAA parts.
Add a constant current source to the cathode followers
Completely upgrade the power supply with electronic regulation and better DC on the filaments.
Modify so that all switches do not carry audio signals but only DC to control high quality relays for all audio switching.
Modify the high level stage to be DC coupledand replace the balance control with a passive type centre tap to ground and the volume control with a blue velvet type wired either conventionally or in shunt mode.
Add in a cc source for the final cathode follower (7C and C22)
Remove the output level pot on the C22 as it simply adds more colouration.
Zed Audio CA
The Marantz 7C and McIntosh C22 are in my opinion totally over rated preamplifiers.
Firstly their RIAA sections are both AC coupled from 1st to 2nd tubes.
Secondly their EQ is active and driven by poorly designed cathode followers.
Thirdly the choice of tubes (ECC83) is certianly not the best.
Fourth the quality of the rotary switches is not good at all.
The power supplies are wimpy and not well designed but in that era this was par for the course.
Of course in their defense the available parts in the 50's and 60's was quite poor compared to what we have today.
We have restored many of these with great results.
Replace every single passive part.
Hard wire the RIAA parts.
Add a constant current source to the cathode followers
Completely upgrade the power supply with electronic regulation and better DC on the filaments.
Modify so that all switches do not carry audio signals but only DC to control high quality relays for all audio switching.
Modify the high level stage to be DC coupledand replace the balance control with a passive type centre tap to ground and the volume control with a blue velvet type wired either conventionally or in shunt mode.
Add in a cc source for the final cathode follower (7C and C22)
Remove the output level pot on the C22 as it simply adds more colouration.
Zed Audio CA
Mantz is on the money. 12AX7s are pretty crappy for cathode follower duty, and a far simpler circuit could be built for $150 in parts around a pair of 6CG7s that would get you better results.
Engineers 50+ years ago could've made a better preamp, but they would've had to have a crystal ball to know that source voltages have gone way up and amplifier input impedances way down, as well as cable lengths tending to increase...
Engineers 50+ years ago could've made a better preamp, but they would've had to have a crystal ball to know that source voltages have gone way up and amplifier input impedances way down, as well as cable lengths tending to increase...
The myth (legend) of the brand is because of their early tube amp products.
The sound of every modern and old classic amp it a result of its parts and the circuits.
The designers (engineers) have choosen the parts due to their electrical properties and maybe for their sound signature. But its no secret that they are an important part in the puzzle of the outcome of the sound of old Marantz gear.
So if someone changes the old passive parts inside for new ones this would alter the sound significantly.
Its like an old Mercedes. Pull the old engine out of the car and install the newest one.
What will happen? The whole character of the car will change. No longer its a classic oldtimer, now its a Frankenstein monster car with a new heart implanted, never been designed that way to drive. Same with replacing every single passive parts.
What you get is a Frankenstein Marantz no longer with the sound of the classic tube amp and no longer worth the price collectors pay for it.
If you want an improved new tube amp with new parts, build a new one. Maybe by copying the old circuit, maybe by starting improvements on it. But never change any parts in a classic component.
It kills its value and its original sound. There aren't many originals outside and still there are people who came to the idea to sacrifice them.
The sound of every modern and old classic amp it a result of its parts and the circuits.
The designers (engineers) have choosen the parts due to their electrical properties and maybe for their sound signature. But its no secret that they are an important part in the puzzle of the outcome of the sound of old Marantz gear.
So if someone changes the old passive parts inside for new ones this would alter the sound significantly.
Its like an old Mercedes. Pull the old engine out of the car and install the newest one.
What will happen? The whole character of the car will change. No longer its a classic oldtimer, now its a Frankenstein monster car with a new heart implanted, never been designed that way to drive. Same with replacing every single passive parts.
What you get is a Frankenstein Marantz no longer with the sound of the classic tube amp and no longer worth the price collectors pay for it.
If you want an improved new tube amp with new parts, build a new one. Maybe by copying the old circuit, maybe by starting improvements on it. But never change any parts in a classic component.
It kills its value and its original sound. There aren't many originals outside and still there are people who came to the idea to sacrifice them.
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I believe the prices paid for "Collectible" and "Performance" can be for very different, not necessarily aligned, motives.
Owning a collectible or vintage piece can be an attempt to recreate a past experience. So if you want "that sound" you heard beck in '65, this is the cost today for a shot at it. It's a long shot too, because you're now a different person; your since learned experience is different than what you had available then, which changes your perception and you're likely physiologically different.
I'm sure many people here know the entire history of audio development since the time of the Marantz 7. They say nothing really significant has happened in the last 20 - 30 years. So it should be possible to find a design that embodies most, if not all of the truly worthwhile deign and construction attributes which most people in the field agree upon.
Just look at MOER's reply; you can start a list -
- interstage coupling
- tube types and topology used
- power supply
- signal switching components
- balance and volume control circuit topology
- active circuit components simply not available 60+ years ago
Perhaps all design aspects for best sound have all been figured out by 20 years ago, but perhaps not 65 years ago. I'd go with something available in more recent days - which would have likely impressed you even more if you heard it back in '65 - had it been available then.
Spend wisely - let the collectors pay top $ for something like that - and then put it up on a shelf for display, like a museum.
Owning a collectible or vintage piece can be an attempt to recreate a past experience. So if you want "that sound" you heard beck in '65, this is the cost today for a shot at it. It's a long shot too, because you're now a different person; your since learned experience is different than what you had available then, which changes your perception and you're likely physiologically different.
I'm sure many people here know the entire history of audio development since the time of the Marantz 7. They say nothing really significant has happened in the last 20 - 30 years. So it should be possible to find a design that embodies most, if not all of the truly worthwhile deign and construction attributes which most people in the field agree upon.
Just look at MOER's reply; you can start a list -
- interstage coupling
- tube types and topology used
- power supply
- signal switching components
- balance and volume control circuit topology
- active circuit components simply not available 60+ years ago
Perhaps all design aspects for best sound have all been figured out by 20 years ago, but perhaps not 65 years ago. I'd go with something available in more recent days - which would have likely impressed you even more if you heard it back in '65 - had it been available then.
Spend wisely - let the collectors pay top $ for something like that - and then put it up on a shelf for display, like a museum.
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You can have your breaker points, 6V electrical systems, surface carburetors, oil bath air filters, etc.
Changing parts like for like isn't like replacing an engine, it's like pulling an old engine apart and replacing rings, bearings, etc. Whether you put a Babbitt bearing back in a block or a modern bearing that is otherwise identical doesn't magically ruin the car.
Ops, and I spent all my savings on the purchase of a Prima Luna Dialogue Two ...... I thought it was the best within my budget .... (it cost me 3000 U $ S)
It has 12AX7, what a disappointment, my friend!
I can not sleep tonight......😉😀
Damn reviewers ! 😡
What you highlighted means nothing. Read the whole sentence, and it makes perfect sense.
jeff
I liked that ...... but I still have the unknown why 12AX7 / 12AU7 is still used today in so many "modern" preamps ........
Is it because they are "cheap" tubes and easy to find ?
🙄
I have done it, and I do not find the sense to speak ill of that tube ...
I would have written something like:
"Despite being a tremendously popular tube, there are better tubes to fulfill the same function somewhat better, although they are somewhat exotic and more expensive"
I said 12AXX7s are pretty crappy for cathode follower duty. Far better choices for that position are not "exotic" nor are they more expensive, they just weren't all that necessary back in the day when this equipment was designed. This isn't exactly the case now.
All the amplifiers that are called integrated have a preamp part and another power .....
You were a bit of a stretch, admit it.
And I wrote it with emoticons, (I think I chose the appropriate ones) a little sense of humor, it helps in difficult times.
And what tubes would you use?
It has to comply with the premises mentioned by me previously, very good for its price and accessibility.
Of course, an excellent connoisseur of valve technology uses others, (for example L.O.) but I do not remember them, yes, all the technicians in the world know 12AX7 .....
Dynaco ST70 estuvo mal diseñado también en la sección preamplificador al elegir 12AX7 ?
O no es un seguidor de catodo ? Realmente no lo recuerdo, ha pasado mucha agua bajo el puente.....( turbulentas ? Simon & Garfunkel ?) 🙂😀
O no es un seguidor de catodo ? Realmente no lo recuerdo, ha pasado mucha agua bajo el puente.....( turbulentas ? Simon & Garfunkel ?) 🙂😀
No cathode followers in any Dynaco circuits, and there was no need for them.
The phono stage was loaded by 200k net, and the line stage was loaded by
a (feedback tuned) 62k. Their power amplifiers had 470k input impedance.
The phono stage was loaded by 200k net, and the line stage was loaded by
a (feedback tuned) 62k. Their power amplifiers had 470k input impedance.
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But its not about changing parts like for like, because those parts are long gone and being seen as obsolete by the industry (they can be bought on ebay for a fortune of money today because they are rare as hens teeth). What they have invented are new parts with different sonic signatures. Some say those have better electrical characteristics but what they for sure have is a different sound signature.
In fact, most parts today are for computer based PCB production of gears rather than a manufacture like production by hand in a hard wiring point to point fashion. That is early Marantz gear! And in that classic, legendary amp now someone who is really smart or want to make a buck puts those new computer grade parts. They REPRESENT and gave the amp its sound signature! Or is the chassis meant to be doing that? Nonsense, its the parts and the circuit and everybody knows that. And for that reason not only the parts are being changed and altered, the circuit is going to be modified by that clever guy, too.
In the end, this Frankenstein amp is nothing. Not a new amp with new technology and not an old amp. Its a Frankenstein monster amp, thats what I'll call those gear.
P.S. An old Van Gogh painting should be restaurated with modern based chemical colors? It's not exactly what professional restorers do with those old paintings. In fact, its the general opposite and nobody would do this. It would be a crime. The picture would be ruined.
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12AX7/ECC83 is a fine tube for what it's designed to do, which is provide relatively high voltage gain into a high impedance load.
12AT7/ECC81, 12AU7/ECC82 are common triodes that make pretty good cathode followers. 6CG7 (6FQ7) and 6SN7 (6N8S) too. Or 12BH7A...
Your choice of 6DJ8/ECC88, 6N6P or ECC99 would make a more macho cathode follower.
Horses for courses, as they say.
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12AT7/ECC81, 12AU7/ECC82 are common triodes that make pretty good cathode followers. 6CG7 (6FQ7) and 6SN7 (6N8S) too. Or 12BH7A...
Your choice of 6DJ8/ECC88, 6N6P or ECC99 would make a more macho cathode follower.
Horses for courses, as they say.
--