McIntosh C29 Vintage Preamplifier

Free Shipping on *ALL* Electronics (Excluding Speakers, Contiguous 48 US States Only)

This is only the second C29 to come through the shop.

We were quickly impressed with the build quality and design which is a big improvement over the (still very good!) C28. It's cool to see how these preamps evolved over the years. 

This example was lightly serviced and is performing beautifully. Super quiet controls and great sound overall. 

Condition is very good with little signs of use inside and out.

Of special note, the metalwork of this C29 is super clean with no signs of rust or pitting.

Your purchase also includes the original owners manual which is a neat addition.

If you'd like to add an official matching McIntosh Wood cabinet in super condition, please just select the option in this listing.

SkyFi Testing Notes:
• Full function test/re-test - PASS.
• Cleaned and tested/re-tested all controls - PASS.
• Unit is very well built and tested very well at the bench.
• Listening Test - PASS.

Click below to add our recommended matching cables from Kimber Kable, all brand new as SkyFi is an official Kimber dealer.

Summit Series Silver Streak Analog Interconnects (PAIR) - RCA Ultraplate or WBT Connectors

Kimber Kable - Phono Interconnects

Please see our photos or the linked manual below for full specifications:

McIntosh C29 Preamplifier - Owner's Manual 

The SkyFi Testing Process for Preamplifiers:

We start with a visual inspection of all internal components to make sure that there are no signs of heat stress or damage. Capacitors are checked for telltale signs of predictive failure including bulging, shrunken wrappers, or physical leakage. We also inspect the PCBs for discoloration from resistors or transistors that may have been running hot. On vintage units we often spot check select capacitors for value and ESR.

When we first power on a preamplifier we connect its RCA output to a Sencore PA81 Power Analyzer which simulates real world loading conditions and gives us an oscilloscope interface. The first order of business is checking that the volume control works smoothly throughout its entire range with acceptable channel balance. This is accomplished by feeding a 1KHz sine wave into one of the preamp’s line level inputs while monitoring the preamp’s output on an oscilloscope. We then switch to a 1KHz square wave to test the tone controls, loudness function, and filters where applicable. During this step we are watching for equal alteration of the test signal by both channels. This also helps us identify dirty controls that will need treatment. Once the basic line stage functions are verified, we test each input individually. This is especially important for devices that use relays to select their sources. If the preamp is equipped with a phono stage we test that as well. We use an inverse RIAA filter which allows us to feed a reference test signal into the phono input with the proper RIAA equalization and level. A square wave or sine sweep is used to verify that the device’s phono stage is faithfully reproducing the RIAA curve. If the preamp under test has balanced inputs and/or outputs these are tested as well.

We finish up our bench testing with a listening test with our bench amplifier and reference speakers. During this test we check for hum or hiss that may not have shown up in earlier testing. We also check that all of the tone controls and filters perform as expected. If the preamplifier has remote control functions these are also tested. Preamps with tube circuits or complicated power supply topologies are connected at our long term test rig for extended stress testing under real world conditions.