RealMarkDeneen

The way it works:: The 12AT is a higher current tube capable of driving a low impedance load. This is the input tube, and it is driving the passive RIAA EQ network, for which I like to use large value capacitors, which in turn means reltively low value resistors. This represent too difficult of a load to be properly driven by a 12AX. So, that's the reason for the 12AT input. Then we need 40dB of gain, so the high gain high Z 12AX is used to get the most of the 40dB gain. So that's why the 12AX follows the 12AT. But we ain't done yet. We need a very low output impedance from the Tercel because we have no idea what it will be connected to in the way of a line stage. So, I opt for another Low output impedance tune with lot's of drive current - - another 12AT. So, there you have it - - the basic" BBX zero feedback, high gain, passive RIAA EQ" phono preamp in a nutshell.

Hi--- Front to back 12AT, 12AX, 12AT. And yes, all tubes are split L/R. Cheers, Mark

What I posted above is the Super Merlin. Apparently, I don't have the earlier first version Merlin. I think the difference is: -First version is 6DJ8 tube, not 6H30 -First version has no remote Aside from that, I think they are the same. Sorry to say I don't own a Merlin of either version so I can't run and look under the hood. Cheers, Mark

Merlin Schematic

Hi Guys.... I did post the Merlin schematic in the main thread I started a few months ago. I can post it again though. I am on my way out to play poker, but when I come back I'll post it. Also, if anyone PMs me - I get an email and that kicks me into a pretty fast answer mode. So, don't hesistate to PM. I try to watch out for inquiries. Thanks for asking...I am doing well. Lots of new spare parts got installed the past 2 years and I'm feeling better than when I was 50! Cheers to all, Mark

Super Merlin---dang! Just missed. There ain't that many of them. I might be waiting awhile.

I found a juicy Peach! It's on the way. But, still possibly interested if others have one to sell. Have not found a Merlin yet....still hopeful.

Oddly, I don't have a single JMA unit. I don't have a TT, which is why I didn't add BBX to the list! I actually NEED a Peach for my stereo! BTW Travis, thanks for the kind words about your BlueBerry.

Hey Duke--- Yeah, for at least one! Mark

Looking buy a Peach and a Merlin. Let me know what you have. Thanks! Cheers! RealMarkDeneen aroadrunner@protonmail.com

@The Dude I'll be interested too. As the hobby moved from visible attributes to mathematical attributes the benefits and peculiarities of "advances" seem harder for me to appreciate.

Hmmm, just noticed this one in my cassette rack. Recorded in 1987. Sounds great--like honey.

Another of the several "black arts" involved in music making that the end listener has precious little insight into. Oh boy, pretty soon we're going get into "imaging" where the real fun begins!

@Travis In Austin Oh, by all means feel free!

As far as I know............no one is going to jail for using the wrong source material.

Getting LPs to sound great was kind of a "black art" back in the 1970s. Not everyone was good at it. And when you could get a "dialed in setup" you had kind of mastered something....like painting with watercolors and not making a muddy mess. It was like being a good chef. Or, the kind of scout that could always start a fire even in the rain. I was not patient enough. But I had a friend who was, and his LP setup was the one everyone wanted to hear a new record on. He had dozens of tiny tweaks, and adjustments and a really good pair of ears too. It's all just games of mastery and aesthetics at the end of the day. Some guys think a Tesla Plaid is a muscle car, others who own a 1970 HemiCuda ain't gonna buy into that. This stereo crap is about personality, eccentricity, weird preferences and what not. It's all fun WTF, right?

40Hz is still fine for all but maybe organ music. Low E on the bass is 41 Hz. And not all that many speakers dig very well below 40 either. I think it was Bell Labs in the `1930s that ran a lot of tests and concluded that "balanced freq response" was more important than extremes at either end. In other words, they reckoned that if you had eqaul octave above and below 1Khz, the sound was "natural." So, in this scheme 60Hz is 4 octaves below and 8Khz us 4 octaves above - so that sounds more natural than say, 60Hz to 20KHz. This "theory" they had was employed in telephonic circuits and for sure their old roatary phones sounded 1000% better on a phone call than a $1400 Apple phone does today. Anyway, where was I? Oh yeah....40Hz. When I was at ADC (makers of the famous QLM and XLM-II phono cartridges) they didn't try to go much below 40Hz either. I think when they made the Boron cantelever cart they got 32 Hz, but that's from my spotty memory of 1980.

It's a sport.

The usual online transaction is: Send me the money, then I'll send you the goods. People are bailing out of the PayPal Gulag in droves. It's a horrible company, with horrible policies. https://truthpress.com/news/paypal-responds-after-losing-thousands-of-accounts/

What year was that magazine? My guess would be 1959.

Now THAT is just bloody funny!

Been awhile, but didn't the Fisher 500 have 7591A output tubes that were hard to source any more? I'm just thinking back 20 years when I remember people scouring the net for them. I could be wrong.

I always wanted to hear the CF-4. It was around before I got into Klipsch speakers and I've never heard them. I have read all sorts of enthusiastic comments about them. If anyone has them - what sort of tone are we talking about? They seem to sell for pretty big $$$, so I assume they have some virtues.

Very nice work. I always liked the tan linen on the original Dynaco Speakers. That "Danish" influence looks very much nicer than boring old black. I never did quite figure out why speaker designers locked onto black with such a death grip. I can't say I've ever had a house where a bunch of big black boxes "enhanced" the decor. Yup - nice setup there! Looks nice in the room!

I believe the "zip" in zipcord refers to the feature that the two conductors can easily be unZIPPED from each other with no tool. (Although I often have to make a tiny slit at the end with an xacto knife). Hmmm? UnzipCord?