Crackling noise from preamp/power amp

Tue 12_Oct-2010

Hi there, I need help.

Yesterday I bought a pair of Used Carver 4000T pre-amp and Carver TFM 45 power amp combo from a private seller. It was rated at 375 W/ch at 8 ohms and 500W/ch at 4 ohms. I was attracted by its power and I really love its retro look. I did not detect anything amiss for the first few tracks of the downloaded demo disc at the seller's home. He was so kind to gave me the downloaded demo disc. But....

I can’t wait to see what sort of headroom this beast (power) will provide. Upon reaching home, I powered up that beast. Tried the same demo disc at very very low volume for fear of damaging my speakers. There were some harsh screeching high frequencies from the first track. It was OK for the next few tracks. On the 5th "no name track" there was loud crackling noise from my 6dB Canon S30 speakers. The noise was still there when I swapped inter-connect. I immediately switched it off and went out for an appointment.

I came home at 9:30 pm, played the same "no name track". The crackling noise was there. So I switched to another amp (Cyrus2 integrated) and… Bravo! I nailed it. The crackling noise went away.

Unconvinced, I returned to the Carver, the same old crackling noise returned. I decided to switch back and forth between the Carver and the Cyrus amp several times. Oh Yes, the Carver problem was definitely there.

It could not be my Canon S30 speakers as it was fully restored last week and was tested OK with my other amps, namely Cyrus2, Roksan Caspian and Pathos TT.

The whole Carver experience was truly scary. I don’t want to blow my speakers. All I want is to enjoy the music. Peace of mind, lah.

Questions

1) How do I diagnose whether it’s the Carver Pre or the Carver Power amp that is at fault? Or both of them before I send them to a Technician.
2) How can the demo disc that misbehaved through the Carver but was transformed to a saint on the Cyrus?

Thank you in advance for your input.

Regards,
KONG
Email: muarpur@gmail.com

probably bad circuitry due to old age ..

Can this decision able to judget by demo CD, are you tested the original CD? only on track 5 sound crackling? how about others?

Come lah ~~! bro , the crakling sound would't only choose on track 5 only, you really funny with this thread~~~~~!

have you test it b4 dealing the stuff? how long u have been test~~~~:?

agree with mofaz, due to age the seller will not provide any warranty for you, this is base on your luck~~~~~!

the only used item that improves with age are cables .. correct or not

Thanks bro.

I agree its old age. Will test it with other discs and post findings.

Regards,
KONG

Could it be due to the worn out volume pot?

You need to isolate whether the problem is from the Pre or Power amp first.

Saw the pics of the amp and you're right they do have that Soviet cold war military hardware retro kind of look ..very cool ...

Tue 12-Oct-2010

Hi there,
Today when I powered up the Carver Power Amp, it was vibrating and making noise so I turned it off. Rebooted it, same vibration and noise.

Yesterday evening, the Carver Power Amp was nearing the end of its life. Today its dead. End of story.

On a happy note, the Carver pre-amp is in working condition when partnered with another amp.

Thanks for your responses and viewing.
Regards,
KONG

Kong seng chee wrote:
Yesterday evening, the Carver Power Amp was nearing the end of its life. Today its dead. End of story.

send it to mr oh to be resurrected. call 012-2060888

Who sold the pre-power amp to you ?

Get the expert la.....to verify it....Like Mr.Oh.

cheers

Third Mr Oh's recommendation.

Fri 15-Oct-2010

Thanks bros. for recommending a professional like Mr Oh. Today I had delivered the dead Carver Amp to him. After witnessing the large amount of hi-end gear at his house for repair, I can comprehend the power of word-of-mouth-recommendation. It is a loud and clear endorsement of his skill.

Regards,
KONG