Musicians Roadhouse

Just purchased a Haze 15 head and love it's light weight and sound! Was wondering if changing some preamp tubes would brighten up the crunch channel a bit. Would anyone know which preamp tube does what in this amp?
Would it be possible to brighten up the crunch channel but leave the clean channel status quo?
Seems that Groove Tubes suggests a long plate AX7 will be brighter than a short plate.
I would like to experiment, but don't know which tube specifically does what..
Thanks in advance.

Hard to say what you have in it right now, did you pull it and look at it. There is a post here on the forum if its a Marshall tube that based off the code you can find out what it is.

http://marshallroadhouse.com/viewtopic.php?f=14&t=11490

The Haze is voiced pretty thick, that's what makes it cool. I think you should try a brighter guitar which will get you more mileage then changing a single tube. Doesn't hurt to try something though, its easy enough but I don't think it going to make that big of difference.

Thanks for the advice!

As for tubes, it's got your favorites in the preamp, JJ's! The glass on the power tubes was wiggly from the base when I got it..Wasn't sure how long term those stock Shugangs would last as they seemed really shoddy so I changed the power tubes upon arrival with Chinese Ruby's. I had a new set as a backup for my Laney Cub 10..another li'l smokin' 6V6 amp. Waiting on a set of E.H's for the power section. I biased it upon arrival to 29mV per tube as I saw those specs on a previous post. Its a restock from Musicians Friend..Got it as new with warranty for 329.00 Thought that was a score!

My issue is that if I engage the bright switch and tweak the crunch channel to my liking, the clean channel becomes very bright for my taste. Without the bright switch, I can find a medium between, but I'm not completely satisfied with the crunch channel. I'm 98 % there, don't get me wrong..but using a Musicman Silhouette Special stock H-S-S - the singles can be bright. I don't have this problem with straight buckers, or a straight strat..Just thought that one preamp tube may be for clean, the 2nd for the gain channel, and the 3rd maybe the phase inverter?

I am too lazy to use the tone control on my guitar!

I have the 15 head also. I found it to be a bit dark on the OD channel at low volumes. The manual does say it was intended to be like that and brightens up as you crank the volume.
Depending on whether you use it as a bedroom amp, or are able to crank it, there are a few mods you can do to brighten it up at low volumes.
One involves cutting one leg of a resistor, the other soldering a wire over a resistors legs. I dont have the resistor numbers right in front of me.
I did the clip the leg of one resistor, and it definitely made the OD channel a bit brighter.

Personally, i never found changing valves actually did a lot. Others would dissagree.

Thanks for the reply. Its gonna be cranked most of the time !! For more fun, I have a 50 watt 1923 head and a 100 watt JMD-1 ..The haze is for the really small bars! Time will tell..haven't gigged with her yet, but looking forward to a simple set up. Me, my guitar, my haze, a Marshall 1936 2x12 or my Bag End 1x12 , Diamond compressor and a wah.

I found this looking around for mods for mine and I will be getting this set soon.
http://thetubestore.com/sba-marshall-haze-mhz15-2.html

Eh..I dumped it..Just not for me..Couldn't get the clean tones & dirty tones dialed in with the shared eq..I think the haze 40 would be more suited for me, if there was a head version.
Haze sounded plinky at low volumes, bass was mushy, treble too dark on dist channel, or too bright on channel 1 with the bright switch on..as they say..different strokes..