Marantz Model 7, 7C, WOOD Case, PRISTINE Cosmetics, Parts, Functioning
Item History & Price
Marantz Model 7/7C preamplifier with wood case, pristinecosmetics, original parts, and functional*.Cosmetics: Thefront panel and knobs are almost flawless. You have to look very closely to seethe tiniest signs of use. The painted side walls of the metal chassis have afew scratches. The rear panel shows the usual dusty white corrosion on theconnectors, plus a few discolorations. The rear could use a deep cleaning thatI did not do. There are no cracked parts. All the original tube ...shields areincluded. The original black plastic caps over the tape EQ adjustment controlsare still there. Serial number is 17xxx.The wood case presents very well, with the famous beveled“cheeks” on either side of the face panel. It does have a few scratches andnicks that are hard to show in the photos, so it’s not as pristine as thepreamp’s front panel. It probably was added later. But it looks very nice withthe preamp inside it. It is the deeper universal size case. It can hold thelarger Marantz 10B tuner as well.Electrical: To the best of my knowledge, all theparts inside look like original unmolested Marantz parts. Please look at thepictures and judge for yourself. I believe that the potentiometers are the originalClarostat units. All coupling caps look like the original “bumblebee/blackbeauty” caps. While I am an experienced with many restorations, I am not aMarantz expert; so I decided not to attempt a full restoration of this special piece.The buyer can choose to leave it in original condition or to restore it as hesees fit.This unit is rated for 117VAC at 50 to 60Hz, intended foruse in the US. (The newer US nominal 120 V is fine). International buyers willneed to consider the appropriate transformers to step up or to step-down the linevoltages to suit this preamp.I did only three things to this piece before I tested it.The power cord’s insulation was dried, cracked and a real danger. So I replacedit with a matching high-quality cord. I sprayed DeoxIT contact cleaner into thecontrols and switches because I knew they would be scratchy from decades of nouse. And I replaced all 6 tubes (even though the originals tested OK) with premiumtubes (see below).With any vintage equipment that has not been powered up inyears, you should never just flick on the power switch, because that is aguaranteed way to blow up the old electrolytic filter capacitors. Too manypeople do just that, including a lot of eBay sellers. Instead, I slowly bringup the AC power using a Variac (a variable line voltage transformer), VERYgradually over an 18-hour period, while monitoring key voltages inside. At the end of the period, when it was at full120V line voltage, I measured all the power supply and tube plate voltages. Allwere within the normal range, indicating that the chemical dielectric layers inthe electrolytic caps had reformed. The old capacitors seem to function, but itwould be wise for a new owner to consider having a technician check them morecarefully and possibly consider replacing them for peace of mind. Beware of anyMarantz 7Cs, or any other high-value vintage pieces that has not been graduallypowered up using a Variac!Tubes: I installed 4 superb-quality Telefunken(Germany) and 2 much-sought-after Mullard (Great Britain) ECC83/12AX7As. TheTelefunkens are in the voltage gain stages, while the Mullards are in thecathode follower positions. These are the optimal choices for a Model 7. All 6tubes (both halves) exceed the specs for brand new tubes on my trusty Triplett3444 tube tester. These premium tubes are the best types that you can use inthis preamp, and these 6 tubes are worth many hundreds of dollars in theirlike-new tested condition.Here are the tests of transconductance of the 6 includedtubes on my Triplett 3444. On this analyzer a new 12AX7A should read 1500, while a tube is considered useable until it falls to 1000. The two numbers witha slash indicate the transconductance of the two sections in each tube:V1 Telefunken 1740/1640
V2 Telefunken 1660/1720
V3 Mullard GB 1560/1760
V4 Telefunken 1660/1720
V5 Telefunken 1670/1520
V6 Mullard GB 1840/1710Function: After this bit of care, this preamp fully functions.I was surprised at how vivid and alive it sounds. I own modern, very expensiveAudio Research tube preamps. This 60-year old Marantz was not embarrassed bythe comparison. It is also surprisingly quiet for a period piece. I checked allthe front panel controls and most of the inputs and outputs on the back panel.Everything I tested seems to function OK. Having said that, I have to sell thisitem in “as-is” condition simply because of its age*. I just cannot guaranteethis piece, because it might work for 15 years or for 15 minutes. My guess isthat you can probably enjoy it for a while though.I made a short YouTube video clip demonstrating this piece“in action”:https://youtu.be/up5Y4JGy2b8Manuals: Bound repro copies of the ProductInformation Sheet, Instruction Manual and Service Manual are included.Shipping: I pack vintage pieces with great love. I installedthe Model 7 inside its wood case, which has internal braces and felt pads to snuglysupport the preamp against jostles. I installed the transit screw into thebottom of the chassis to lock down the floating tube sub-chassis duringshipment. This should be removed for use.I then covered all sides of the wood case with foaminsulation board cut to fit and taped together with insulation tape. A doublelayer of foam with cut-outs protects the switches and knobs. This cocoon wassurrounded by bubble-wrap and then placed inside a heavy oversized box. Theshipping weight is over 36 pounds (!), so shipping costs will not be cheap, butyou can be assured that it should survive rough handling and long-distanceshipping.In the rare case that an item is damaged in transit, buyermust contact seller within 3 business days of delivery. Buyer MUST retain allbox and packing materials in order for us to file an insurance claim. Failureto retain packaging will void buyer’s right to receive insurance reimbursementor credit for shipping damages.Buyer is responsible for all shipping charges, duties, VAT(value added tax), customs fees and any other fees, if applicable. Beforebidding or buying, please check with your local postal carrier/customs officefor more information about any possible fees. Under no circumstances is theseller liable for any additional fees charged to buyer. Seller will not adjustor falsify an item’s declared value for customs or importing purposes.All shipments will be insured. In cases of high value items, additional insurance may apply - above eBay's calculated shipping price.This item can also be picked up in the South Florida area, butonly after the sale is complete, to prevent “no shows”.Terms: *Like all vintage equipment that we sell, thisitem is sold “as-is”, with no warranties, no refunds and no returns, notwithstandingany representations made elsewhere herein. When an item is listed "as-is"we do our best to describe the item honestly in text and pictures. Buyer shouldsatisfy himself regarding this item’s condition by viewing the photos provided.Photos are part of the description. A Buyer should expect that this item mayrequire service at any point in time, due to its age. Sale is final.Items must be paid for within 3 calendar days of winning theitem unless "Buy It Now" is used which requires immediate payment. Payment must be made by PayPal (only).Under no circumstances shall seller be held responsible forany loss, damage or malfunction (including personal injury) resulting from orcaused by buyer’s use of our items.Per eBay policies, each offer or bid that you place entersyou into a binding contract to complete a transaction. If a potential buyercannot fully accept these terms and the risk that it implies, do not bid or buy.*******Thank you for looking!
V2 Telefunken 1660/1720
V3 Mullard GB 1560/1760
V4 Telefunken 1660/1720
V5 Telefunken 1670/1520
V6 Mullard GB 1840/1710Function: After this bit of care, this preamp fully functions.I was surprised at how vivid and alive it sounds. I own modern, very expensiveAudio Research tube preamps. This 60-year old Marantz was not embarrassed bythe comparison. It is also surprisingly quiet for a period piece. I checked allthe front panel controls and most of the inputs and outputs on the back panel.Everything I tested seems to function OK. Having said that, I have to sell thisitem in “as-is” condition simply because of its age*. I just cannot guaranteethis piece, because it might work for 15 years or for 15 minutes. My guess isthat you can probably enjoy it for a while though.I made a short YouTube video clip demonstrating this piece“in action”:https://youtu.be/up5Y4JGy2b8Manuals: Bound repro copies of the ProductInformation Sheet, Instruction Manual and Service Manual are included.Shipping: I pack vintage pieces with great love. I installedthe Model 7 inside its wood case, which has internal braces and felt pads to snuglysupport the preamp against jostles. I installed the transit screw into thebottom of the chassis to lock down the floating tube sub-chassis duringshipment. This should be removed for use.I then covered all sides of the wood case with foaminsulation board cut to fit and taped together with insulation tape. A doublelayer of foam with cut-outs protects the switches and knobs. This cocoon wassurrounded by bubble-wrap and then placed inside a heavy oversized box. Theshipping weight is over 36 pounds (!), so shipping costs will not be cheap, butyou can be assured that it should survive rough handling and long-distanceshipping.In the rare case that an item is damaged in transit, buyermust contact seller within 3 business days of delivery. Buyer MUST retain allbox and packing materials in order for us to file an insurance claim. Failureto retain packaging will void buyer’s right to receive insurance reimbursementor credit for shipping damages.Buyer is responsible for all shipping charges, duties, VAT(value added tax), customs fees and any other fees, if applicable. Beforebidding or buying, please check with your local postal carrier/customs officefor more information about any possible fees. Under no circumstances is theseller liable for any additional fees charged to buyer. Seller will not adjustor falsify an item’s declared value for customs or importing purposes.All shipments will be insured. In cases of high value items, additional insurance may apply - above eBay's calculated shipping price.This item can also be picked up in the South Florida area, butonly after the sale is complete, to prevent “no shows”.Terms: *Like all vintage equipment that we sell, thisitem is sold “as-is”, with no warranties, no refunds and no returns, notwithstandingany representations made elsewhere herein. When an item is listed "as-is"we do our best to describe the item honestly in text and pictures. Buyer shouldsatisfy himself regarding this item’s condition by viewing the photos provided.Photos are part of the description. A Buyer should expect that this item mayrequire service at any point in time, due to its age. Sale is final.Items must be paid for within 3 calendar days of winning theitem unless "Buy It Now" is used which requires immediate payment. Payment must be made by PayPal (only).Under no circumstances shall seller be held responsible forany loss, damage or malfunction (including personal injury) resulting from orcaused by buyer’s use of our items.Per eBay policies, each offer or bid that you place entersyou into a binding contract to complete a transaction. If a potential buyercannot fully accept these terms and the risk that it implies, do not bid or buy.*******Thank you for looking!
