PCB ref Marantz 7C 7-C Tube Pre Amplifier Amp (Stereo) - eBay (item 320449773277 end time Jan-15-10 02:35:14 PST)
VACUUM TUBE LINE PREAMP MODULE - 7C BASED DESIGN - eBay (item 260534041961 end time Jan-13-10 11:08:57 PST)
just wondering if anyone experienced one of these kits? if not perhaps some speculation?
...and witch kit seems better, and witch is cheaper in the end? i have little to no budget here, probably selling old projects to fund new ones....
VACUUM TUBE LINE PREAMP MODULE - 7C BASED DESIGN - eBay (item 260534041961 end time Jan-13-10 11:08:57 PST)
just wondering if anyone experienced one of these kits? if not perhaps some speculation?
...and witch kit seems better, and witch is cheaper in the end? i have little to no budget here, probably selling old projects to fund new ones....
Are you sure these are kits ? First one clearly states it's just the PCB + assembly manual (a sheet of paper, I presume). The other one appears more vague (the ungodly ugly combination of colors and huge amount of text is why I couldn't bring myself to stomach that entire description) and I'm not sure what is actually included.
Assuming those were kits they'd still require PSU material and tubes at the very least. If money is tight at the moment, tube preamp probably shouldn't be at the top of your priority list anyway. Sleep it through, those Chinese aren't going to run out of PCBs anytime soon 😉
Assuming those were kits they'd still require PSU material and tubes at the very least. If money is tight at the moment, tube preamp probably shouldn't be at the top of your priority list anyway. Sleep it through, those Chinese aren't going to run out of PCBs anytime soon 😉
As for your first link, the kit with parts and tubes, minus case, from the same dealer, costs $238.00:
DIY Kit ref Marantz 7C Tube Pre Amp (Stereo) Standard - eBay (item 320453819271 end time Jan-24-10 03:39:18 PST)
And the full kit from the same dealer costs $399.99:
Full Kit ref Marantz 7C Tube Pre Amplifier (Stereo) - eBay (item 320453820561 end time Jan-24-10 03:43:31 PST)
Plus $89 shipping for the full kit.
You can get similar kits for much better prices.
As for your second link, it says nowhere what the "kit" actually contains.
An example for better offer would be, for instance, this:
LS-22 pre-amplifier, assembled & tested (minus tubes) for $73.70:
DIYCLUB
Plus 3 12AX7 for $36.18:
DIYCLUB
Plus LS57 tubes HT rectifier and regulator, assembled and tested, including tubes, for $104.52:
DIYCLUB
Plus 100W R-Core Transformer for $34.84:
DIYCLUB
Which makes the total kit, minus box, $214.40 and you can add there a case for $41.54, for a total of $255.94 plus shipping, which is calculated by weigh and for the full kit, including transformer and case can be around $100.
Still a better offer than your first link, however a total of about $356, including shipping, is something to consider. Yet, it's better than the total of about $489 for a full kit, including shipping, for a full kit from your first link.
Even all the above offers are very expansive compared to the following SET integrated tube amplifier, shipped from Canada, which I heard high praises of its' sound quality:
MP-401 EL156 Integrated Amplifier [MP-401] - $599.99 : Musical Paradise - Audio Art
For about $600 plus shipping from Canada.
DIY Kit ref Marantz 7C Tube Pre Amp (Stereo) Standard - eBay (item 320453819271 end time Jan-24-10 03:39:18 PST)
And the full kit from the same dealer costs $399.99:
Full Kit ref Marantz 7C Tube Pre Amplifier (Stereo) - eBay (item 320453820561 end time Jan-24-10 03:43:31 PST)
Plus $89 shipping for the full kit.
You can get similar kits for much better prices.
As for your second link, it says nowhere what the "kit" actually contains.
An example for better offer would be, for instance, this:
LS-22 pre-amplifier, assembled & tested (minus tubes) for $73.70:
DIYCLUB
Plus 3 12AX7 for $36.18:
DIYCLUB
Plus LS57 tubes HT rectifier and regulator, assembled and tested, including tubes, for $104.52:
DIYCLUB
Plus 100W R-Core Transformer for $34.84:
DIYCLUB
Which makes the total kit, minus box, $214.40 and you can add there a case for $41.54, for a total of $255.94 plus shipping, which is calculated by weigh and for the full kit, including transformer and case can be around $100.
Still a better offer than your first link, however a total of about $356, including shipping, is something to consider. Yet, it's better than the total of about $489 for a full kit, including shipping, for a full kit from your first link.
Even all the above offers are very expansive compared to the following SET integrated tube amplifier, shipped from Canada, which I heard high praises of its' sound quality:
MP-401 EL156 Integrated Amplifier [MP-401] - $599.99 : Musical Paradise - Audio Art
For about $600 plus shipping from Canada.
If you really need a pre-amp, which is doubtful, what does it need to do? Step up voltage? Drive long cables? Select between sources? Just a volume control? Phono input?
I don't know if the Marantz 7c was a classic, but it sure is old. Tube tech has improved markedly since that time, despite the solid state revolution. Just as a 68 Barracuda was a hot car, these days we also like to stop, turn corners and not die in minor accidents.
Go to bottlehead.com, and look at the foreplay kit. Good stuff, and lots of good support. Or search here for aikido, which you can buy as a PCB. Good support on that too.
Don't be another ebay junk victim. Too many posts here about how somebody bought this "kit" on ebay and it caught fire, etc.
Or just go to Radio Shack and buy a 100K stereo audio pot and put it in a box. Much better than you might expect, and dirt cheap. Much, much better, actually.
I don't know if the Marantz 7c was a classic, but it sure is old. Tube tech has improved markedly since that time, despite the solid state revolution. Just as a 68 Barracuda was a hot car, these days we also like to stop, turn corners and not die in minor accidents.
Go to bottlehead.com, and look at the foreplay kit. Good stuff, and lots of good support. Or search here for aikido, which you can buy as a PCB. Good support on that too.
Don't be another ebay junk victim. Too many posts here about how somebody bought this "kit" on ebay and it caught fire, etc.
Or just go to Radio Shack and buy a 100K stereo audio pot and put it in a box. Much better than you might expect, and dirt cheap. Much, much better, actually.
You might run a search over at Audio Asylum. I think Michael Samra has played with their "kits" and said good things. I'm not sure it would be a good beginner project. There are, of course, many more proven options, like Bottlehead or the Aikido. I'm watching Jim McShane's page with a great deal of interest.
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
NOOOOO EEEEBAYYYY , please do as suggested, sleap on it, do some more research as money seems to be an issue. if not, go ahead, you will be the next person trying to get your money back, ebay is not worth looking at, a waste of time. sorry if I insulted you, but it is the truth, "you get what you pay for" advice is free, and I would listen to these guys, they know what they are talkng about as I myself am still learnig.
Member
Joined 2002
Gota love hongkong for doing this, finding a design and selling it for HUGE amounts of $$$, it's quite sad. Might get into trouble for this comment, but well it's how i strongly feel, everything on ebay for parts and kits from hongkong is pass produced CRAP! 100% JUNK just fake crap.
hmm.....linestage using 12AX7, lots of caps, resistors and feedback...
why would a linestage require that amount of gain? its a collector's classic alright, the original equipment that is.
why would a linestage require that amount of gain? its a collector's classic alright, the original equipment that is.
thank you all much for the constructive criticism, its what i was looking for.
as for my project, i have no idea, i am just tinkering around with some old projects and looking for some thing to keep me busy over the winter, the ice fishing is poor.
my goal here is to get a tube amp to power a cassette player also fm radio and my pc sound card. the cassette player needs the pre amp, i am working with a few old el84 amps. i have access to many salvage parts, tiring to keep cost under 50, witch is why a PCB board is ideal, the rh84 was suggested to me in a separate post, i am considering it for all i need is a choke for 20$ but for now i am just researching and studying for this project
as for my project, i have no idea, i am just tinkering around with some old projects and looking for some thing to keep me busy over the winter, the ice fishing is poor.
my goal here is to get a tube amp to power a cassette player also fm radio and my pc sound card. the cassette player needs the pre amp, i am working with a few old el84 amps. i have access to many salvage parts, tiring to keep cost under 50, witch is why a PCB board is ideal, the rh84 was suggested to me in a separate post, i am considering it for all i need is a choke for 20$ but for now i am just researching and studying for this project
Aikido Amplifier Octal Stereo Printed Circuit Board
Aikido Amplifier Octal Stereo Printed Circuit Board
this looks good, thanks
just curious on how much of this amp's components can be salvaged from vintage radios?, as in, are there any componets that must be newer or specific to this amp?
a parts list would be asome?
i just am limited on funds, and have access to many vintage audio components, so i need to hunt down the right project.
Aikido Amplifier Octal Stereo Printed Circuit Board
this looks good, thanks
just curious on how much of this amp's components can be salvaged from vintage radios?, as in, are there any componets that must be newer or specific to this amp?
a parts list would be asome?
i just am limited on funds, and have access to many vintage audio components, so i need to hunt down the right project.
This should have everything you need...
Index of /Product_PDFs
Aikido would be a great first project! It's well documented, and plenty have built it. I think just about every question about it has been answered around here already.
I built the octal PCB as a line stage, and it was so simple, I decided to build the aikido phono amp point to point (no PCB).
and, I dont think anything has to be new as long as the value of the component is close to what you need.
Index of /Product_PDFs
Aikido would be a great first project! It's well documented, and plenty have built it. I think just about every question about it has been answered around here already.
I built the octal PCB as a line stage, and it was so simple, I decided to build the aikido phono amp point to point (no PCB).
and, I dont think anything has to be new as long as the value of the component is close to what you need.
Hey, also John has some other designs available now which need fewer components than the aikidos. I've never tried them, but I'm sure they are solid designs and will probably cost about 1/2 of what the aikido would. (1/2 the tubes and caps involved)
Personally I would go with the Aikido, it's a much better design and benefits from current design practices which have evolved substantially since the Marantz 7 ("C" stands for "cabinet") was designed 50yrs ago. (Some of the newer Broskie designs would also be worth investigating obviously.) It is also unquestionably an ethical choice.. (What's that?) 🙄
A lot of these Asian "kits" are IP rip-offs in that the company in question has cloned a design without the permission of that design's owners. Clones of anything that was made by a still existing company are for the most part unauthorized copies. In a lot of cases the design is even a bad copy of the original and offers nothing like the level of performance of the original, which I'd say is appropriate. Caveat Emptor!
Probably all "kit" pcb based copies of CAT or CJ pre-amplifiers on eBay for example are the result of IP theft. Large companies like LVMH (Louis Vuitton Moet Hennessy) have the wherewithal to enforce their IP and product identity rights, but most audio companies haven't the legal or financial resources.
There are lots of little Chinese companies making original products with considerable merit, I would give those guys my business over anyone making a clone of someone else's design without permission.
A lot of these Asian "kits" are IP rip-offs in that the company in question has cloned a design without the permission of that design's owners. Clones of anything that was made by a still existing company are for the most part unauthorized copies. In a lot of cases the design is even a bad copy of the original and offers nothing like the level of performance of the original, which I'd say is appropriate. Caveat Emptor!
Probably all "kit" pcb based copies of CAT or CJ pre-amplifiers on eBay for example are the result of IP theft. Large companies like LVMH (Louis Vuitton Moet Hennessy) have the wherewithal to enforce their IP and product identity rights, but most audio companies haven't the legal or financial resources.
There are lots of little Chinese companies making original products with considerable merit, I would give those guys my business over anyone making a clone of someone else's design without permission.
Last edited:
Member
Joined 2002
This has got bugger all to do with the original question. Does anyone know where the design for the Lite Audio GA 31A was ripped off from ? It looks too complex to be Chinese, surely it was stolen.
Member
Joined 2002
I don't doubt it for a moment, I just wonder where they pinched it from. Maybe it is an ARC design ?
Member
Joined 2002
Maybe we can buy one and experiment 🙂 buy one then call the manufacture that actually has the schematic 🙂
Actually I respectfully disagree with Jaon's post. IMHO selling copies or supposed copies of long out of production electronic items is fine by me, especially copies of something that old. Weather or not the copy can replicate the sound of the original is something the buyer would have to determine himself... The price in the board kits is certainly reasonable enough. As far as selling copies of currently produced stuff or stuff with current standing patents that IMHO is a very bad thing!
Mark
Mark
- Status
- Not open for further replies.