A delicious sound above the din of Mexico City

You hear it from a block away: an amplified, singsong call with an uncanny power to slice through the urban din. The tone is cheap and tinny -- as kitschy as a sound can be.

And it’s my favorite in Mexico City.

Listen now, as it nears, the nasal-toned male voice stretching out syllables and pauses, again and again, into a verse so familiar it could be the unofficial anthem of this vast city, a kind of culinary call to prayer.

Ri-costa-ma-les oaxa-que-ños!” blares a loudspeaker on the vendor’s tamale cart. “Tamales oaxaqueños!” “Tamales calien-ti-tos!”

Go to any neighborhood in Mexico City, from gritty to grand, and at some point during the evening you might hear it. The recorded call, always in the same hypnotic voice, is pumped from countless speakers aboard countless tamalero pedal carts. Step up and order your delicious Oaxacan tamales.

In some variations, the sales pitch offers red or green sauce, but always promises tamales that are “calientitos!” Nice and hot. Then it repeats again, with the same robotic cadence: “Ri-cos ta-ma-les oaxa-que-ños . . .”

The streets and sidewalks of Mexico City act as a vast, impromptu marketplace, and the sounds of that trade rise in dizzying variety -- some amusing, some annoying, all as distinctive as birdsong.

From our apartment in a bustling neighborhood near the center, we hear many of them. The bellowing steam whistle of the yam seller’s pushcart. The shrill whistle of the knife sharpener on his bike. The jangling of the town crier’s bell that says it’s time to bring your trash to the corner. The baritone lowing of the gas delivery tout: “Gaaa-a-a-s!” The balloon vendor’s trilling, rapid-fire toot.

But none tickles quite like the tamalero’s trademark pitch. Say “Ricos tamales oaxaqueños” here and you’ll get a knowing nod, often with a chuckle. After eight months living in Mexico City, my 5-year-old daughter still sprints to the window to scan for the three-wheeled cart at the first hint of “Ri-cos . . . "

You can find recordings on YouTube. (Look for the toddler’s rendition and a partial, high-pitched version by a man wearing thong underwear on his face.) Some residents have even downloaded the tamales call as the ring tone on their cellphones.

Adding to the mystique, no one is sure of the origin of the taped pitch. By one account, the recording was made by a vendor who was slain on the job; colleagues adopted his call as a form of homage. A competing version holds that some Chinese entrepreneurs own the trademark. Another says the taped voice belongs to a fellow named “Bones,” still another that the recording comes from the neighboring state of Puebla.

There are lots of noise-weary folks here who’d love to rip out the tamalero’s tape. (One commentator compared it to “a horror movie.”)

One day, maybe I’ll hate the endless invitation. For now, though, I love its flawed, improvised quality and disregard for peace and quiet.

To me, it sounds just like Mexico City.

Ellingwood is a Times staff writer.