Review: Marantz 7t Preamplifier


Category: Preamps

Want a surprise? Listen to a Marantz 7T preamp. I have for years been pining away for a 7C to go with my Klipschorns and rebuilt/upgraded Dynaco Mk IV mono blocks, however they were priced out of my reach. But one day I was reading Stereophile and they had an article with the designer of the 7C, he mentioned that he was rather satisfied with his first SS designs (the 7T preamp and model 15 amplifier) and that with some upgrading (mostly swapping out old caps and low quality resisitors) they could be made to sound quite like a 7C...well that was all I needed to hear, I could take no more...I grabbed a 7T at an EBay auction (they always go for less than $500) and sent it to have its caps and resistors swapped out for new, better qulaity units. After a rough two weeks impatiently waiting for the unit to arrive I finally got it out of customs (I live in Central America) and hooked up, replacing a Creek passive preamp I had inserted in the meantime. I really was not prepared for what I heard...Lushness, an expanded and deepened soundstage, a the while maintaining great clarity of sound. It gave me the sound I had reserved, in my mind's eye/ear, for the 7C or any other top quality tube preamp. It seemed as transparent as the Creek passive preamp (a treatise which I tested, unscientifically, by swapping the two in and out a few times) but did impart a warmth to the midrange, expand the soundstage and seemed to "light from within"(forgive the borrowed term but it really fit what I felt I heard) my music. No test equipment, so I cannot tell you if it rolled off the highs or changed the response curve significantly, however to my ears it still had great rendition of cymbals and piano notes and I felt less fatigue while listening to my cd collection (which contains many of those terrible early rock releases so hard to listen to if your components don't cooperate). Best of all it is a full featured preamp with a myriad of switching and tone control options, and even has varied curves available for the phono section if you have older LPs. All in all I am now convinced that the pruchase of a 7C is a waste of money. If you have the scratch, perhaps as a collectors item I would justify it, but if you are like me; looking to vintage audio components for that "golden age of audio" sound but with a modern level of performance then a re-furbished 7T is just the thing, great sound, low price. Try it!

Associated gear
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Similar products
Harmon and Kardon, Creek
sunnysal
I've picked up a 7T a while back to see how it would mate with my original Marantz 8. I've never gotten around to hooking it up yet. My curiosity is getting the best of me now, so i'll have to give it a try. As you mentioned though, i'm sure that at least the caps need to be replaced. Sean
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yes by all means means replace some caps and resistors, but get the schematic and only replace those that are active in producing sound, you'll save some money that way...there are a lot of caps and resistors that are rarely/never used...give it a try, I think you'll be amazed...what are you using now?
I'm using a modified Dynaco Pas 3 in that system right now. I've got another Pas 3 that i've got to "gut" and will be doing a complete redesign / rebuild on in the future. By the time that i'm done with it, i'll simply be using the core components ( chassis, transformer, tubes & sockets ) but it will be completely different in terms of circuitry. Sean
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those dynaco units can be fun to work on...but put some time into the 7T and you'll have a world killer preamp, really the equal of the best stuff out there...regards, tony
I'm interested in doing this upgrade. Where did you get it done? Sounds very interesting!
Old post I know. I own a 7T that was restored, and it sounds okay. Recently purchased and original 7T in pristine condition. Every component is original.  The sound stage is so deep, wide, and transparent that it has made me rethink ever restoring another component unless it’s out of spec and in obvious need.
My tech has confirmed that the original untouched 7T unit exceeds its original specs-all across the board.  It is super quiet and at the moment the finest sounding preamp I’ve ever owned.
Comparing it to my model 7 tube preamp, the 7T is a bit quieter, and the bass much tighter.  Mids are very similar and the highs are a bit softer/smoother on the 7 tube model. You would be hard pressed to tell them apart, as their voicing is so similar.  Just saying, really, really give pause to having something restored because it’s old.  I know I will.
Norman