#1
Hello guys,

so last week i bought a peavey 6505MH 20 watt amp head, i was going to buy it with a cab but due to some low income no speaker cab yet..

so far i've been playing it with headphones and it kicks ass, but i've noticed something.
sometimes when i play i accidently unplugg the headphones, and when this happens i can hear the sound i usualy hear from my headphones coming from the amp... with no speaker or what so ever.
is this normal? i only noticed this 2 days ago, also when its turned on and i slightly tilt the amp i hear a screaming noise but when i put it down normally its back to normal.

also this is my first tube amp so i'm a noob to this.
#2
martin.ouwehand
You really should NOT be playing a head without a cab plugged in. It's a good way to fry the transformer of the amp. At least have a dummy load plugged in or wait to get a cabinet. The amp head has no speakers, so I have no idea what you're hearing after you unplug your headphones.

As for the screaming noise, it could be a faulty pre-amp tube.
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#3
there's no dummy load in that amp.
you have been absolutely frying the output transformer.
that sound you hear with no headphones plugged in is the sound of your transformer screaming.
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#5
People, 6505MH (MICRO HEAD) does have a dummy load. There is a speaker defeat button right in the back. Hopefully TS has it engaged.

https://assets.peavey.com/literature/manuals/118738_30842.pdf

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Last edited by MaaZeus at Jun 28, 2016,
#6
i just found out that maybe one of the pre amp tubes is bad.
if i touch it with a pencil very lightly i can hear a loud tick, this does not happen on the other tubes, does that mean the tube is bad / broken?

also i understood that the 6505 MH can be played without a cab. (it also said on the box: "record without a cab!!!")
but Maazeus, what do you mean with: "hopefully TS has it engaged"?

Edit:
Oh yeah, so far i've been playing with the speaker button on 'defeat'.
not becouse i knew i should, but becouse it really sounded like shit on my headphones without it.
just way way to loud and crushing noise..
anyway i think i'll just let the amp rest for a while until i get my cabinet, i'm scared now that i'll break it :c

oh yeah also that strange screaming noise when i tilt the amp, that was just my headphones sort of disconnecting ._.
derp
Last edited by martin.ouwehand at Jun 28, 2016,
#7
Well if the MH follows suit with its larger siblings, get some JJ preamp tubes (12ax7) (I like eurotubes.com) and call it a day.

Don't be afraid to use features of your amp. If you have questions call Peavey or the place you purchased it from. Peavey has a forum section on their site under support as well if you want to go that route.
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#9
martin.ouwehand

I just meant that hopefully that hopefully you had the dummy load engaged. Tube amps should NEVER be turned on without cab or a dummy load attached. Doing so can deteriorate and blow up transformers fast.

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#11
It won't make any sound when you do plug in a cab. If it works everything is fine.
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