Question for you guys that bias your own amps

[ZL1hawk]

I just installed new EL34 power amp tubes in my Splawn Nitro and I use a Compu-Bias to check the plate voltage. All 4 power tubes are matched really well but I decided to run them a little hot. I'm just over the normal bias setting for EL34's and just to be on the safe side I'm wondering if any of you do the same? Or do you prefer your amp to be biased a little cold? The Nitro sounds great to me and most people I've talked to said it isn't a problem since I'm just slightly over the range for EL34's.

I actually find the EL34's to be more to my liking than the KT88's I originally had in the amp.

[DonP]

What was wrong with the KT88's?

[ZL1hawk]

What was wrong with the KT88's?

The 88's were fine I just wanted to switch things up. One player who has posted a good number of clips with his Splawn's on a few forums is a guy named Windsen Pan, I think he helped setup the Splawn website to, but his clips using EL34's sound really good so I decided to give the new tubes a go. I'm sure I'll go back to the 88's at some point.

[markD]

i used to bias the EL34s hotter. these days i run them on spec or a hair colder. the reason for going a hair colder is that i felt it allowed me to have better control of the amp at higher volumes and reduced excessive compression.

[ZL1hawk]

i used to bias the EL34s hotter. these days i run them on spec or a hair colder. the reason for going a hair colder is that i felt it allowed me to have better control of the amp at higher volumes and reduced excessive compression.

That's just at higher volumes right? Did you ever notice over time the bias would fluctuate? The difference was minimal but I always had to keep a record when I was using KT88's and make adjustments. I'm wondering if my amp would be better off overall biased on the cold side rather than a little hot.

[slo100]

I would run mine a bit cold for amps I would gig with. AC power varies so much at the various bars and clubs I played that I wanted to stay in a safe range in case I ended up somewhere with hot voltage. If you run a power supply with a transformer supplying constant voltage I would be more comfortable running hot. It also depends on the amp's capacity to adopt to variances in bias settings.

[ZL1hawk]

Do you find there is a break in period for power tubes? I'm wondering with more hours playtime on these new EL34's they will eventually hold its setting and let the bias remain static.

[Chad]

I usually run them around 5% to 10% below the max recommended setting. That allows for some drift and other factors. When installing brand new tubes I might check it a couple times in the first month or so. Then maybe once every 6 to 12 months after that.