A solution for replacing the original 2-gang volume potentiometers in McIntosh C26 preamplifiers. These potentiometers frequently suffered from poor gang error across the pot’s rotation.
More information will be available soon.
A solution for replacing the original 2-gang volume potentiometers in McIntosh C26 preamplifiers. These potentiometers frequently suffered from poor gang error across the pot’s rotation.
More information will be available soon.
This kit is designed to replace the original nickel plated steel RCA jacks used in the McIntosh C26 preamplifier with a set of gold plated Switchcraft connectors. The original connectors tend to get loose with age, and in models that utilized an aluminum mounting plate, the interface between the connectors and the plate was susceptible to galvanic corrosion over time. This kit eliminates these issues while maintaining the original star ground scheme.
The kit includes a replacement RCA mounting plate, 21 RCA connectors, all necessary mounting hardware, and a printed installation guide with pictures.
Please note that installing this kit is an extensive process that will involve drilling out the original isolated rivets, removing the cables attached to all RCA jacks, mounting the new jack plate in place, and re-soldering all cables. If you do not have prior experience doing work of this caliber on similar electronics, please have a qualified service professional install this kit in your unit.
Click here to download the installation guide
This kit is designed to replace both multi-section can capacitors used in the power supply section of the McIntosh C26 preamplifier. Two custom capacitor mounting boards and four 220uF/200V Nichicon electrolytic capacitors are included. These provide a slight improvement in supply filtration compared to the original parts which, depending on serial number, typically included one 160uF/200V and one 200uF/150V capacitor per can. If you need different capacitor values, feel free to send us a message and we can order them for you.
Parts Included
Click the link below to download the installation guide
This kit is intended as an easy way to mount new radial electrolytic capacitors when replacing 1 inch diameter multi section can capacitors with 1.5 inch mounting hole spacing CTC. This design was modeled after an Astron A-25-65 can. These were often used in vintage radio equipment.
Up to three different caps can be installed, and they all share a common lead located in the center. The center common lead has a trace connecting it to one of the mounting holes, making it convenient to tie to chassis ground; if you need to isolate this board from chassis ground, take a look at our insulation kit. The spacer board sits between the new caps and mounting board and adds clearance between the turrets and cans of the caps. Four turrets provide a robust post for wires and other components to attach to when installing.
If you use a positive-common configuration, be wary that the cans of electrolytic caps are often tied to the negative lead (cathode), but not always. Thus, voltages may exist between the cans depending on the circuit, so space them apart as needed.
Based on IPC-2221B guidelines, this board is not to be used in circuits that may see peak voltages above 450 V assuming a typical negative-common configuration.
Specifications:
Note: Dimensions are nominal values. Outline dimensions may vary by ±0.15mm, and hole sizes by ±0.076mm.
This is an FPGA implementation of the MN4760S line memory used in the time base corrector (TBC) sections of some LaserDisc players. This board was designed specifically for an MLD7020 with a dead line memory, breathing some new life into a unit that would have otherwise been a paperweight due to the original part no longer being manufactured.
This board is not available for order at this time. Please contact “parts (at) proaudioe.com” if you would like additional information.
Click here to download the installation guide
This kit is designed to replace the original riveted RCA jacks used on the back of McIntosh MAC4100 receivers. A custom RCA mounting board re-uses the original rivet holes for attaching to the back panel and provides plated holes for soldering the input/output shielded cables. The mounting board uses 2 ounce copper and wide traces to connect each RCA jack to their respective solder pads, and the star ground arrangement of the original wiring scheme is maintained. A matte black cover plate is included for replacing the original black shrouds around the RCA jacks.
Please note that the installation process for this kit is fairly complex and will involve drilling out the original RCA rivets, soldering the new RCA jacks to the mounting board, stripping and soldering each shielded cable to the new board, and mounting the new board in place. We recommend testing your unit before installation to ensure everything is working as expected, and then taking plenty of pictures throughout the process to use as reference.
Note: The included black machine screws will be slightly shorter than those in the listing photos to avoid having extra thread length sticking off of the back.
Parts Included
Additional Details
This is a replacement power guard display PCB for McIntosh MC2500 amplifiers. This board is used to mount four bi-pin incandescent lamps which indicate the power guard status for both channels of the MC2500.
Includes one unpopulated PCB and one 5 pin right angle Molex connector. Lamps are not included. Boards may have minor cosmetic surface defects, but this will not impact their functionality.
The hole sizes for the lamps were increased to accommodate PC pin sockets (not included) for simplifying future lamp replacement. If you have LED replacements for 7382 lamps that are designed to be powered with AC (11.2 VAC is typical according to the MC2500 schematic), they should also work just as well on this board.
Specifications:
Click here to download the installation guide
This is a replacement kit for the GE multi-section can capacitors used inside the McIntosh MC2100, MC2105, and MC2300 power amplifiers. These cans were stamped with McIntosh part number 066-095. Other models may also use this can. High quality, genuine Nichicon capacitors rated for operation up to 105°C are used to ensure a long operational lifespan, and a custom PCB with thick 2 oz. copper provides a robust and elegant mounting solution. Four wiring turrets facilitate the connections to each of the four caps. No more gutting the old cans and sticking new caps inside!
Includes four Nichicon capacitors, one cap mounting PCB, one spacer PCB, a hardware kit, and a thorough step-by-step installation guide.
Installing this kit will require soldering, drilling out the original can’s mounting rivets, and stripping/attaching wires in a tight space. If you do not have prior experience safely testing and repairing amplifiers at the component level, please have a qualified professional install this kit in your unit.
The following capacitor values are included:
Note: The capacitor symbols (square, triangle, half-circle, dash) on the cap PCB were arranged based on the orientation of the original can in the MC2300. Other models, such as the MC2100, typically had the cans oriented differently, meaning the position of the symbols on this board may not align with your original installation.
Click here to order: Assembled, PCB Only
Click here to download the installation guide: Assembled, PCB Only
This is a new-production input preamp board for the McIntosh MC2100, MC2105, and MC2300 power amplifiers. This board follows the original component layout closely, and no changes were made to the original circuit design. Available assembled and tested, or as an unpopulated PCB.
The new PCB is double-sided and uses 2-ounce copper, plated through-holes, an immersion gold finish, and matte black soldermask. Silkscreen reference designators and symbols are provided on both sides. Robust wiring turrets replace the original hollow posts that cables solder to. All component footprints are sized to fit the original parts. In addition, all axial electrolytic capacitors have footprints for radial parts of various sizes, both input film caps support two different lead spacings, and both electrolytic output caps can be substituted with film caps of the appropriate physical size. A capacitor sizing guide is included with unpopulated kits.
Assembled boards are built using high quality components, including Vishay MRS25 series low noise metal film resistors (1% tolerance, 600 mW, 50 ppm TCR), Nichicon electrolytic capacitors (UPM series for supply filters, UKZ for audio stages), WIMA film capacitors, and new transistors. All assembled boards are burn-in tested for 24 hours and run through an Audio Precision analyzer to confirm that they meet the performance specifications listed below.
Parts Included (Assembled Board)
Parts Included (Unpopulated PCB)
Typical Performance
Typical performance of both channels (Audio Precision analyzer, 2 Vrms output from DUT):
Note that these specifications apply to the preamp board by itself and do not reflect the overall performance of your McIntosh amplifier. We have tested an original MC2100 input board in the same manner and found that this new board slightly exceeds the performance of the original.
We recommend testing your unit first to ensure it is working properly. If you are repairing your unit, please make sure your symptoms are originating from the preamp board before you replace it. Replacing this board will not resolve problems present in the rest of the unit, such as the power supply or amplifier sections. If you have not replaced the original multi-section can capacitor in your unit’s power supply, we recommend doing so; we offer a replacement capacitor kit with a custom designed PCB for this task.
Please do not attempt to install these boards if you are not thoroughly familiar with safely diagnosing, repairing, and testing amplifiers at the component level with test equipment (signal generator, oscilloscope, load, etc.) and a current-limited power supply.
Click the link below to download the installation guide
March 2024: These boards are currently out of stock, however we are working on a revision that will use all modern-production semiconductors and an improved circuit design.
These PCBs are intended to replace damaged driver boards in the McIntosh MC2300 amplifier. The PCB itself was also used in other models such as the MC2100 and late-revision MC2105 units, and the new board should work in these models with some component changes. Bear in mind that the silkscreen reference designators/symbols are based on the MC2300 schematic, which largely matches the schematic of late-revision MC2105 units, but does not match the schematic of the MC2100. Early revision MC2105 units (s/n 10M01 to 26M07) used a slightly different PCB with multiple circuit and layout changes that would require modifications to the board to implement.
Includes two unpopulated PCBs, four TO-39 spacers, and a thorough install guide with re-drawn schematic, board layout, and parts list.
Please do not attempt to populate and install these boards if you are not thoroughly familiar with safely diagnosing, repairing, and testing amplifiers at the component level with test equipment (signal generator, oscilloscope, load, etc.) and a current-limited power supply.
Here are the main differences between this board and the original:
Specifications:
Other Notes: