Speaker crack above 50% power Vienna acoustics Mahlers

Richrat · « **on:** 20 Jul 2024, 06:25 pm »

I have a pair of Vienna acoustics Mahlers, powered by a primare SPA 23. ( I KNOW, I KNOW , BUT ITS WHAT I HAVE FOR NOW). There is a crack in sound above 50% power, sounds like a scratch in an album. Speakers say 4 ohms on back, tech data online says 6 ohms. Amp says 8 ohms on back , tech data says it can run 4ohms 300watts, 1 channel driven. Amp was serviced, no issues. Can this amp really drive these monsters ? Can it be a speaker issue? Need help. Thx

FullRangeMan · « **Reply #1 on:** 20 Jul 2024, 08:37 pm »

Try other amp or other speakers for testing.

Phil A · « **Reply #2 on:** 20 Jul 2024, 09:34 pm »

Quote from: Richrat on 20 Jul 2024, 06:25 pm

I have a pair of Vienna acoustics Mahlers, powered by a primare SPA 23. ( I KNOW, I KNOW , BUT ITS WHAT I HAVE FOR NOW). There is a crack in sound above 50% power, sounds like a scratch in an album. Speakers say 4 ohms on back, tech data online says 6 ohms. Amp says 8 ohms on back , tech data says it can run 4ohms 300watts, 1 channel driven. Amp was serviced, no issues. Can this amp really drive these monsters ? Can it be a speaker issue? Need help. Thx

Here is the Stereophile review measurements - https://www.stereophile.com/content/vienna-acoustics-mahler-loudspeaker-measurements "More important, the impedance drops below 3 ohms throughout the bass, which will mandate using an amplifier with good current delivery."

WGH · « **Reply #3 on:** 20 Jul 2024, 09:46 pm »

Welcome to AC!

Are you the original owner of the Vienna Acoustics Mahler? I ask because the Stereophile review of the Mahler's is 24 years old.
https://www.stereophile.com/floorloudspeakers/296/index.html

Robert Deutsch wrote:

"The Mahler was able to play at high levels with ease and smoothness, maintaining the level of detail that was characteristic of lower playback levels. In its ability to play at very high levels without sounding strained, the Mahler surpassed every other speaker I've had for review."

If you bought the Mahler used then they might have been played at a very high levels for a long time. I have had woofers sound crack at high levels, one time it was the voice coil bottoming out, the other time it was the lead wire from the woofer binding post to the spider, it had an intermittent break at high excursions.

You will have to crawl around to find where the noise of coming from. Once located switch speaker wires to see if the noise moves with the speaker or stays on the left or right channel. One way it is a bad driver, the other way is a bad connection or electronics.

Richrat · « **Reply #4 on:** 20 Jul 2024, 11:03 pm »

I’ve read that article before, thx. The crack is coming from both speakers at the same time, from what I can detect, the crack may be from the top front 7 inch driver. Note: both dust covers are off, one blew off , other came loose and was vibrating so I removed it. I am not the 1st owner, I’m 99% sure previous owner was not someone who cranked them up. He’s not the original owner though.