Little Dot I+ Tube Rolling
Jan 21, 2014 at 9:28 PM Post #1,711 of 3,154
High gain can aggravate an existing issue... My LD1+ never was microphonic when it was stock with any grados. I'd try tapping the tubes to see if its them causing the noise... Even try another pair.
 
Jan 22, 2014 at 12:29 AM Post #1,713 of 3,154
Hey guys, I was thinking about getting a new set of tubes for my I+. Im looking for something a little bit more dry and airy sounding, I'm currently using the basic 5654 tubes. The thing is, i think i lost my jumpers, so are there any tubes that would work in my current situation?
 
Jan 22, 2014 at 1:21 AM Post #1,714 of 3,154
  Hey guys, I was thinking about getting a new set of tubes for my I+. Im looking for something a little bit more dry and airy sounding, I'm currently using the basic 5654 tubes. The thing is, i think i lost my jumpers, so are there any tubes that would work in my current situation?

 
Well, first, you can go to Radio Shack or any electronics part store and buy computer jumpers:
 
http://www.ebay.com/itm/Computer-Jumpers-Qty-15-Color-Black-Size-2-54mm-0-1-inch-Spacing-/141171663163?pt=LH_DefaultDomain_0&hash=item20de7ca13b
 
GE 6HM5 fits your description and it works in the 5654 setup:
 
http://www.ebay.com/itm/Vintage-GE-General-Electric-6HM5-6HA5-Vacuum-Tube-NIB-NOS-New-USA-/141143867937?pt=Vintage_Electronics_R2&hash=item20dcd48221
 
Jan 22, 2014 at 7:27 AM Post #1,715 of 3,154
High gain can aggravate an existing issue... My LD1+ never was microphonic when it was stock with any grados. I'd try tapping the tubes to see if its them causing the noise... Even try another pair.

Yeah if I tap the tubes then I get the same noise... Guessing that this shouldn't happen?
I'm pretty sure that my amp is set to low gain, but should I try switching it anyway?  It won't damage my headphones will it?
 
Jan 22, 2014 at 11:09 AM Post #1,717 of 3,154
  Yeah if I tap the tubes then I get the same noise... Guessing that this shouldn't happen?
I'm pretty sure that my amp is set to low gain, but should I try switching it anyway?  It won't damage my headphones will it?

 
You can try changing the gain setting, but I doubt it will make any difference. Some tubes are microphonic and some are not. If the microphonic noise is driving you nuts, then replacing the tube(s) is the only solution. On the other hand, if you usually stay somewhat immobile while you listening, then maybe it is something you can ignore.
 
Jan 22, 2014 at 1:22 PM Post #1,718 of 3,154
   
You can try changing the gain setting, but I doubt it will make any difference. Some tubes are microphonic and some are not. If the microphonic noise is driving you nuts, then replacing the tube(s) is the only solution. On the other hand, if you usually stay somewhat immobile while you listening, then maybe it is something you can ignore.

Ok thanks for that!
I have some 'Valvo' 6CQ6 tubes.  Will maybe try some of the mullard m8161's :)
 
Jan 22, 2014 at 3:38 PM Post #1,719 of 3,154
  Ok thanks for that!
I have some 'Valvo' 6CQ6 tubes.  Will maybe try some of the mullard m8161's :)

 
Hi SJWorne,
 
I tried the same Valvo 6CQ6, and found them to be very microphonic indeed, though quite good sounding after a period of burn-in.  I replaced them with the Mullard M8161 (CV4015) which are not at all microphonic.  I can tap them and hear nothing through my headphones.  They are mil-spec, so probably have more robust innards, less prone to vibration.  Additionally, the Mullards sound quite a bit more refined in every way than the Valvo 'equivalent'.  Like all Mullards, the M8161 is on the warm side, but in a very likeable way, if warm is your taste.
 
Jan 22, 2014 at 5:11 PM Post #1,720 of 3,154
   
Hi SJWorne,
 
I tried the same Valvo 6CQ6, and found them to be very microphonic indeed, though quite good sounding after a period of burn-in.  I replaced them with the Mullard M8161 (CV4015) which are not at all microphonic.  I can tap them and hear nothing through my headphones.  They are mil-spec, so probably have more robust innards, less prone to vibration.  Additionally, the Mullards sound quite a bit more refined in every way than the Valvo 'equivalent'.  Like all Mullards, the M8161 is on the warm side, but in a very likeable way, if warm is your taste.

Hi Munky, thanks very much for clearing that up, glad it's not just my amp/tubes! :)
I can't say i've had enough experience with tubes and warm/cold sounding tubes/amps/DAC's, but I will get some to try out! :)
Thanks again!
 
Jan 22, 2014 at 5:26 PM Post #1,721 of 3,154
   
Sorry, G... I just couldn't help myself... I changed the tubes and the op amp... The first thing I noticed was that there was no break-in hum at all with the WE 408A tubes... I also noticed that they don't light up as much as the 6J1 tubes... I did shift the jumpers to '408A'  from '6J1'... J1 and J2 still open...
 
One helpful hint:  Mark the rear of the bottom plate with a piece of tape so it goes back the same way... Otherwise, the holes don't line up very well, and you can strip out a screw... Also, you need to hold the bottom plate down while starting the screws, also to align the holes...
 
Now for the break-in...

Or you can cut a opening on the bottom plate.
 
Jan 22, 2014 at 5:32 PM Post #1,722 of 3,154
  Hey guys,
I get a hell of a lot of microphonics from my headphone cable... is this normal?
I'm using Grado Sr125i's, and maybe about half the length of cable gives me a lot of 'dinging' noises if i knock it or even touch it.  
Is this anything to do with gain? If it was set for the higher impedance could this be the case? And would it damage my headphones?
 
Thanks!

I have the same problem but only with MULLARD 6AM6S/M8083 tubes try swapping tubes.
 
Jan 23, 2014 at 9:49 AM Post #1,725 of 3,154
  Or you can cut a opening on the bottom plate.

 
Ilove: I'd like to be able to do that; however, I currently have my LD1+ on top of my digital piano, and with the WE408A tubes, the unit runs a lot hotter... I know the top of the Yamaha CP 300 is metal, and that it can take a certain amount of heat... But I don't know how much before it might discolor the paint... Perhaps the cut-out would make the unit run cooler, but the heat would likely radiate out of the bottom cut-out, possibly making the heat transference to the piano top issue worse... So, there's a question-mark there...
 

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