Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: geontemt on May 01, 2018, 05:44:30 PM

Title: Interference
Post by: geontemt on May 01, 2018, 05:44:30 PM

I have a Crack with speedball, HD 650, MacBook Air, Tidal, and RCA to 3.5 double shielded cable (tried 2 different of the same brand, a 3 foot and 12 foot with no difference).  I have 2 different kinds of interference.  One sounds like radio but non stop talk that fades in and out.  The other sounds like a faint router that fades in and out.  Moving to another position or room seems to improve it for a little bit.  The interference is primarily in the left channel.  If I unplug the RCA from the source (my laptop or phone) I still hear it but if I unplug the RCA from the crack it stops and is dead quite.  The interference is very quite but after listing for a while it becomes more noticeable, I don't think its getting louder just more noticable.  I live in an apartment in the city so there is a lot of opportunity for interference.  Any thoughts on fixing it?

Thanks
George

Title: Re: Interference
Post by: Tom-s on May 01, 2018, 10:29:13 PM

Is your Crack connected to ground?

A tube shield for the ECC82 could help here.

Title: Re: Interference
Post by: geontemt on May 02, 2018, 02:42:30 AM

Yes, I live in a new building and we have a ground.  I am not sure if the amp is receiving the interference or if the cable is acting as an antenna.  The cable is iXCC cable from amazon but is supposed to double shielded. 

Also, the volume knob does not increase or decrease the interference.

Title: Re: Interference
Post by: Paul Birkeland on May 02, 2018, 03:36:07 AM

If you use your phone as the audio source and move your lap top 10-20 feet away, is the noise still present?

Title: Re: Interference
Post by: geontemt on May 07, 2018, 11:22:24 AM

It seems like it is my laptop.  It takes about 15 minutes to hear the interference.  At first I thought it was after the amp warmed up or my ears but it seems to stop when I use my phone instead. 

I am not sure why it takes a while for the interference to become noticeable if it is the computer but it is very noticeable during pauses or track changes on loud music but then starts to fade but stays noticeable, any ideas?

I am thinking about getting a chromecast audio  since it appears to my my computer.

Title: Re: Interference
Post by: Doc B. on May 07, 2018, 12:23:40 PM

Perhaps something in the laptop is heating up and that is making it noisy. At any rate, you now know the source of the noise.