12AX7 MM/MC Phono Preamplifier PCB ref VTL

[spurlte]

Has anyone used or seen the Marantz 7 phono preamp PCBs? Can you tell me which is better, this one or Jim's Audio? Tube Phono RIAA Stereo Pre Amplifier PCB Marantz 7 | eBay

[SY]

The only thing worse than ripping off the Marantz trademark to sell cheap boards is ripping off the Marantz trademark to sell cheap boards that have nothing to do with the Marantz circuit. Not that the Marantz circuit was all that great, but still, this is absolutely terrible ethics. If they'll steal from Marantz, don't you worry that they'll steal from you?

[spurlte]

Originally Posted by SY

The only thing worse than ripping off the Marantz trademark to sell cheap boards is ripping off the Marantz trademark to sell cheap boards that have nothing to do with the Marantz circuit. Not that the Marantz circuit was all that great, but still, this is absolutely terrible ethics. If they'll steal from Marantz, don't you worry that they'll steal from you?

I agree and I am sorry but, I am a disabled vet who lost both legs over there as a radio man (life expectantcy minus 90 seconds--take out the communication), and I was bored to death until I found diyaudio.com. It has threads that use chinese PCBs board successfully and with my monthly disability benefits I would never be able to afford any of Marantz's appliances. I am not planning to sell what I build and can't see how this would hurt Marantz. Adobe Photoshop is available mysteriously and those who learn from cheaply gotten Photoshop programs have gone on to buy the original Adobe programs when they turn professional. So, Adobe wins. So can Marantz, no? But I still agree with you and I firmly believe that this practice of the what the Chinese are doing is ethically and morally wrong and should teach us Americans what we have to do to rebuild our working force and economy. What am I to do? Stuck being a rock and a hard place in Chicago.

[SY]

I'm also in the Chicago area (Lake County), and they wanted to put me into Signal Corps back in the draft days (I was well aware of the life expectancy of a 2nd Lt in SC, which approached zero as an asymptote). So you have my sympathy and understanding.

If you can lay out what it is you want the preamp to do (gain, impedance, phono or not), people here may have some suggestions on reputable vendors of good quality designs.

[spurlte]

Originally Posted by SY

I'm also in the Chicago area (Lake County), and they wanted to put me into Signal Corps back in the draft days (I was well aware of the life expectancy of a 2nd Lt in SC, which approached zero as an asymptote). So you have my sympathy and understanding.

If you can lay out what it is you want the preamp to do (gain, impedance, phono or not), people here may have some suggestions on reputable vendors of good quality designs.

Thanks Lieutenant. I am now building a, yes chinese, Krell clone--KSA 100 with many from all over the world. These are really nice people who have taken me under their wing and it has been a rewarding adventure. Keeps me up all hours of the night. It's been very expensive too. I limit using 10 percent of my benefits per month. It may take long to complete this amp, but as I understand it, it will be a special amplifier I will enjoy for many years. I will be leaving Chicago for Ann Habor, Michigan. They have a great VA hospital there. So long, spurlte

[SY]

Ann Arbor is a great town, you'll enjoy it.

Most of the Chinese "Marantz" pres will have a struggle driving the low-ish input impedances of a solid state amp. You might look at something like an Aikido from John Broskie. There's probably a lot of decent designs out there in kit form with some oomph that will work well for you.

[spurlte]

Originally Posted by SY

Ann Arbor is a great town, you'll enjoy it.

Most of the Chinese "Marantz" pres will have a struggle driving the low-ish input impedances of a solid state amp. You might look at something like an Aikido from John Broskie. There's probably a lot of decent designs out there in kit form with some oomph that will work well for you.

I will go with your suggestion. Too many good reviews and testimonies about Aikido products. There goes my exuberance again. Better than slot machines although I don't gamble. If I give anyone money, I want something solid back. spurlte

[Boydk]

Just got hold of the another schematic (DIY Gene).
(I built the AnalogMetric version some time ago with a few alterings.... Sowther step-ups, running mm-mode with 6.3 volt filament and 4 6N2P-EV instead of 12AX7, have probs. with a slight humming still, and of course the lack of bass, other than that the sound is quite good.)
The schematic differs in these points:
R 14 is 1Mohm
R 15 is 1Kohm
R 16 is 24Kohm.
This is the only difference, C6 is still 10nF.
Anyone on what this would do???

[spurlte]

Originally Posted by spurlte

I will go with your suggestion. Too many good reviews and testimonies about Aikido products. There goes my exuberance again. Better than slot machines although I don't gamble. If I give anyone money, I want something solid back. spurlte

Sy, I ran into this thread about the Aikido pre-amp.
SP-6 Light with ECC801S on the horizon already. Please check it out. It would seem that the pre-amp fizzles out over time. Maybe you can send suggestions their way?

[Graffity]

Anybody knows what is the output resistance of this chineese 12AX7 shematic? I don't know how to measure it.