Hafler DH110 Preamp Repair (Ep. 212)

[@MichaelBeeny]

Two possible problems. Number one, I have found in the past sometimes these phono leads are twin core as expected but it is not a screened lead. It's just black and red conductors. These will, of course pick up hum and handling noise. Hum level varying with position. Problem 2. A phono connection will hum if a second earth lead is not connected to the separate earth terminal on the turntable.

[@MyLittleBitOfEverything]

Turntable RCA cords - Or cords used for turntables also include a ground wire to attach the turntable to chassis ground via the screw near the phono in jacks to help with the ground hum. Without that added wire you will tend to run into ground hum issues because of the high gain needed for cartridges.

[@Poppinwheeeeellllllieeeeez]

I'm hoping there is a vintage long form repair coming up soon.

[@TrevorsBench]

If I can get the repairs out of the way, I can focus on larger projects. I have lots planned for 2024

[@2tallB]

Demand your money back! 😂

[@Dutchamp]

Those styroflex caps i think they are over the input like 47pF capacitains to the load of a phono cartridge. Pretty normal for mm stage. The higher the capacity the more high frequency cut so the more bass you hear in the front.

[@holgers5216]

some phono preamps do not like to have an 'open/floating' input either, something to keep in mind, a small resistor from input to ground usually helps that......ha...you did that...

[@alexismethenitis]

Great work as always!

[@ronkelley5348]

I'd expect the tonearm cable to have an earth lead to connect to the ground pin on the pre-amp

[@killertimes]

Whatever happened to that Citation 12?

[@TrevorsBench]

Waiting for it's turn on the bench

[@killertimes]

@@TrevorsBench cool. looking forward to it!

[@alanarmstrong2323]

I have a H K 900+ in need of repair

[@johnsenchak]

They would play those damn things at maxuim sound levels for hours. One of them powered a big floor sub-woofer The whole building would vibrate from the music levels My point here is the Japenese made some series auido euipmen which could be punished for hours and never fail You just don't see that any more in electronics. The chinese are not doing it I tried getting a job at Krell ,in Orange Ct. I never got a call back. They made some total kick a$$ equipment You should try getting some Krell euipment on the bench That preamp needs to be earth ground bonded on it's chassis This then ground bonds the amp and turntable through the RCA cables

[@Thetimeisnow78]

What the hell is a Hafler??

[@petenamlook18]

If you've never heard of David Hafler, do yourself a favour and search the internet.

[@TurntableGuy]

Ever heard of google?

[@robertdavis5714]

10 second relay................Just another reason I stay clear of those red/white RCA cables, and probability Made in China.

[@TrevorsBench]

I just used them in the video as a example

[@Dutchamp]

Most terrible chinch cable in the bin with them.