J Corder/Bottlehead-Modded Technics RS-1500USWith Charles King-Modded Analog Engineering usedJ Corder/Bottlehead-Modded Technics RS-1500US With Charles King-Modded Analog Engineering  Tape Preamp - PRICE DROPThis is a state-of-the-art custom J-Corder Technics RS 1500 2 and 4 track reel-to-reel tape deck named “The Blues” plus a Charles King-modified Analog Engineering vacuum tube IEC/NAB tape preamp. B...3600.00

J Corder/Bottlehead-Modded Technics RS-1500US With Charles King-Modded Analog Engineering Tape Preamp - PRICE DROP

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Condition
6/10
Payment methods

Contact seller after sale to pay viaCertified check

Ships fromBeverly Hills, CA, 90210
Ships toUnited States
Package dimensionsunspecified
Shipping carrierFedEx
Shipping cost$200.00
Original accessoriesBox
AverageResearch Pricing

This is a state-of-the-art custom J-Corder Technics RS 1500 2 and 4 track reel-to-reel tape deck named “The Blues” plus a Charles King-modified Analog Engineering vacuum tube IEC/NAB tape preamp. Both are in good working order and have no issues. Both were recently gone through by an experienced technician and given a clean bill of health. The tubes in the Analog Engineering tape preamp have all been tested and all tubes test strong with plenty of life left on them.

The J-Corder Technics RS 1500 does have some cosmetic issues, however these are mostly on the side panels. I have tried to show these cosmetic defects in the pictures, however there may be a few others the camera did not pick up.  Hence the 6/10 rating. The easiest way to overcome this would be to either prime and paint the sides or source new ones from J-Corder or one of the other aftermarket RTR specialists. There is also a compromised corner on the bottom left side of the pre-amp’s faceplate as you can see in the pictures. This happened during shipping at one point and, like the blemishes on the deck, has no effect whatsoever on the sound.  One word of warning -you will need a preamp or integrated amp that has a decent amount of gain as the levels coming out of the preamp are on the low side.

The J-Corder-modified deck originally cost $7500.00 and the Analog Engineering tape tube preamp retails for $2495.00 before the modifications. So it would cost you about $10,000.00 to get these two pieces of gear in new condition today.

Included in the asking price are the original shipping container from J-Corder, the original Technics soft plastic dust cover, the two Darklab/Revox hub adapters pictured in the photos plus the original J-Corder custom blue Technics reels also shown in the pictures. You will want to source some spacers for playback as the metal reels have slightly warped over time and may rub against the deck. A better idea would be to source plastic reels for actual playback and keep the metal ones for display. Plastic sounds a lot better – especially plastic reels that do no require a hub adapter – just fewer pieces to impart their own noise.

Please note that the RS 1500 has both the tape counters and LED meters removed from the circuit.  There are no record heads in this highly-modded unit.  If you are in the market for a great playback tape deck, this is the one. I will not separate these two units so please do not ask.

Buyer pays Paypal fees and is responsible for covering ALL real-life shipping costs. I am constantly amazed by buyers who think that 75lbs of gear split between three boxes shipped with insurance across the country costs only $25. It doesn’t.  Plan for something in the vicinity of $150.

Here is some general information about both units taken from the listing by the original owner:

 

J-Corder-modded Technics RS 1500 2 and 4 track tape deck:

Our quest for the Holy Grail began with the purchase of a rebuilt Technics RS-1500US reel-to-reel tape machine (manufactured between 1978 to 1986 and retailing then in the neighborhood of $1600), from Jeff Jacobs at J-corder.com. Jeff, for those who don't know him, is a preeminent Technics reel-to-reel technician with over 35 years of experience as both a dealer and authorized technician for a number of audio manufacturers. While I paid a lot more for my Technics machine than if buying off eBay, I had the piece of mind that Jeff had completely stripped down, serviced (including replacement with upgraded brake pads), recalibrated and then bench tested my deck to ensure it met manufacturer specs. Furthermore, Jeff inspects and tests the tape heads; if they measure less than 70% of tip depth, he replaces them. For those searching for the ultimate, sexy looking reel-to-reel tape machine, Jeff also customizes the Technics reel-to-reel machines and gives them unique names like The Blues, The Natural, The Pearl, Jade or Black Crown Jewel. Running anywhere from $4000 to $8000 (or more), these tape machines are unmatched works of art. Owners can customize their decks even further by adding some color matched Dark Labs NAB hubs and/or J-corder or Dark Labs customized reels to their machines.

 

Step Two: Hot Rodding the Deck

After Jeff worked his magic on my deck, the J-corder Technics deck went to Dan at Bottlehead Electronics to eke out that last couple of percent of performance from my deck. These performance upgrades included hot rodding the Technics for use with outboard electronics and use of an after market IEC plug, disconnecting the tape counter and level meters and upgrading the tape path.

Every machine that comes into Dan's shop undergoes a rigorous inspection and replacement (if necessary) of any worn tape path and alignment of components in the tape path for straight and consistent tape travel over the heads and a flat, well centered tape pack on the reels. The Bottlehead tape path modifications also reduce friction on the tape surface and scrape flutter and make the tape sit a little closer to the heads when running in fast forward and rewind. "The end result" according to Dan, "is a machine that handles tape extremely well and sounds cleaner, with better low level resolution and snap and begins to approach the sound quality of a pro machine."

But prior to carrying out any of the above modification, Dan adjusts the deck's brake tension. According to Dan, the one common problem he's encountered "is setting the correct brake tension, regardless of how new the stock felt brake pads look." After experimenting with different brake lining materials, Dan found a material that meets the tension specifications in both directions. All the decks that come into his shop have their brake pads retrofitted with this material. Dan also mentioned that, "it's remarkable how much better a RS-1500US works with the proper brake tension. The tension rollers never pop up at stop and the reels stop very quickly at runout. With the tape kept in good tension the pack seems to come out better when you stop and start a lot too."

The next order of business is aligning the ever so critical tape path. First, a careful visual alignment using some established reference points is a starting point for static alignment; the bulk of the alignment adjustment is made with shims. Then once the visual alignment is complete, the travel of the tape over the rollers, guides and heads and the tape pack position is noted. Dan has found that if the tape path alignment is done with enough care some sources of friction in the tape path can be removed and some guide surfaces can be replaced with lower friction materials resulting in subtle improvement in dynamics.In addition, Dan disconnects the tape counter because the belts create speed instabilities that degrade the sound. As Dan says, "You can tell how much the counter influences the smoothness of the reversing idler if you've ever heard the dreaded screech of the cheesy tape counter belts and pulleys when you rewind. The tape counter is not that accurate anyway."

Last but not least, Dan hot rodded my machine for direct head output and use with the Analog Engineering Charles King modified IEC/NAB vacuum tube preamp.

Analog Engineering Charles King-modified vacuum tube IEC/NAB tape preamp:

Preamp Circuit:

The phono preamp uses three triodes per channel: one half of two 6N1P-EB type tubes for gain, and one half of a 12BH7 for cathode follower output. The 6N1P is a current production Russian tube; its high performance specs and sound quality have made it a favorite alternative to pricey NOS valves.

The RIAA equalization is split; the first EQ constant is implemented between the two 6N1P gain stages, and the second EQ constant between the second gain stage and the cathode follower. The cathode follower is direct coupled, with an output impedance of roughly 500 ohms, so the circuit can easily drive long interconnects.

Constant Current Sources (CCS) are used for loads on all the tubes, and LEDs are used within the CCS for cathode bias. The LEDs are selected for their low noise, dynamic impedance, and RF stability in the circuit.

If you’re not an engineer, don’t worry if this all sounds complicated. The simple result of the circuit is rich, smooth, detailed analog sound in all its glory.

Layout and Lead Dress:

Since layout and lead dress are vital in analog circuits, a great deal of attention was given to the placement of key components. No detail has been spared. Signal leads are kept very short, to minimize both magnetic loop area and capacitance to other wiring. On the signal return loop, ground connections all return to a low impedance ground plane.

Grid stopper resistors are used on each vacuum tube grid, to damp any resonance associated with grid capacitance and lead inductance.

High current heater wiring is elevated from the circuit board on heavy gauge shielded twisted pair wire.

Experienced craftsmen assemble each preamp by hand with loving pride. We treat every unit as if it were going to be hooked up to our own system.

Power Supply:

The power supply has been designed to minimize noise and exhibit extreme stability. It all starts with a high-performance torroidal power transformer. The 6V heater circuit powers the 6N1P tubes, and is exceptionally quiet. The circuit is rectified with Schottky diodes, and feeds a choke input filter for an extra degree of common mode noise rejection. Capacitive bypasses around each heater eliminate any remnants of VHF hash.

The 12V heater circuit is rectified with Schottky diodes, and employs an RC (Resistor-Capacitor) filter. The 12V heaters are bypassed in the same manner as the 6V heaters.

The high voltage is rectified with SiC Schottky diodes, and is well-filtered with a three-stage RC network. This filter supplies two shunt regulators, providing dual mono regulated power for the preamp.

What does all this tech talk mean to you, the listener? An inky, blacker-than-black background, from which music leaps out with astonishing clarity.

Questions for the seller
How recently was the unit checked? Do you have the receipt from the unit being checked? Thanks
I can put you in touch with the technician who gave it a clean bill of health in Feb. 2105.

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