Mod 50 sounds like it may explode!

[richedie]

I installed a new 250 fuse and all is well with the 5881s for now.

 

[bruce egnater]

I'd like to clarify the function of the 250mA tube fuses. Each tube has fuse associated with it. The idea is that if a power tube shorts, the fuse for that tube will blow before other damage can occur. The fuse is there to help protect the amp from a shorted power tube. The original value of 250mA was right for the production tubes that were current years ago when the amps were first designed. Tube specs have changed over the years as different tube maufacturers come and go. Current production EL34 tubes tend to draw a bit more current than older production models. This is why we increased the recommended fuse value from 250mA to 315mA or 400mA. It simply prevents a nuisance fuse blowing which can happen with some EL34 tubes using the 250mA fuse when playing at high volumes. The MOD50 panels have been relabeled 400mA for about a year. Yours (richeddie) simply has the earlier labeling. It is common knowledge that the quality/reliability of current day EL34 tubes is not very good. FYI, the poweramp design in the MOD50 is pretty much just a conventional P/P circuit design not unlike proven designs from Marshall, Fender etc. There is no reason power tubes should not last as long in the MOD50 as with any other amp.

Thanks!!
Bruce Egnater

 

[Valtiel]

I'd like to clarify the function of the 250mA tube fuses. Each tube has fuse associated with it. The idea is that if a power tube shorts, the fuse for that tube will blow before other damage can occur. The fuse is there to help protect the amp from a shorted power tube. The original value of 250mA was right for the production tubes that were current years ago when the amps were first designed. Tube specs have changed over the years as different tube maufacturers come and go. Current production EL34 tubes tend to draw a bit more current than older production models. This is why we increased the recommended fuse value from 250mA to 315mA or 400mA. It simply prevents a nuisance fuse blowing which can happen with some EL34 tubes using the 250mA fuse when playing at high volumes. The MOD50 panels have been relabeled 400mA for about a year. Yours (richeddie) simply has the earlier labeling. It is common knowledge that the quality/reliability of current day EL34 tubes is not very good. FYI, the poweramp design in the MOD50 is pretty much just a conventional P/P circuit design not unlike proven designs from Marshall, Fender etc. There is no reason power tubes should not last as long in the MOD50 as with any other amp.

Thanks!!
Bruce Egnater

Thanks for the info Bruce, very helpful!

 

[TheGrooveking]

I had the same problem....weird hummmmmmsss, popping noises, snaps, crackles, pops, etc...... not the tubes, not the speakers nor the guitar......the problem?????:
Crappy Egnater Chinese made amp.....no mistake....tried 2 of them.
What solved the problem eventually?????? Took the amps back to Guitar Center and continued playing my Mesa, Rivera and Sewell amps....problem solved! Try it and see if it works for you too.

Buy an Egnater and always take it back!

Obviously you are ignorantly biased against Egnater. First off the thread is about the US designed and built amp, the MOD50. I'll matched Egnater's quality against anything you could throw up against it, so your post here is to do what, just show your stupidity? I've had more problems with Mesa amps by far than any Egnater product I've had.

Bruce & company have always been solid in supporting their products, so instead of coming on here and spewing your stupidity, you should direct your energies towards something than needs improving, like yourself. I'm sure there are some self help classes at your local liabrary for how to improve your social skills and until you get help why don't you leave the forums to those who can constructively interact with others.

TheGrooveking

 

[richedie]

Just my preference, but I much prefer equipment built in the US. Again, just my preference.

This may have a typical power amp design but I know the transformer is top notch! Better than the garbage you get in production amps from Marshall and others. A buddy of mine put a Mercury Magnetics in each of his amps(not Egnater) and the difference is very noticable.

That said, thanks for the info Bruce! Makes complete sense and changing the fuse was a snap. I'll just have to wait to get some 315 or 400mA fuses. In the mean time I hope I can get some Tung Sol EL34B in the coming months. I can't give up the EL34 habit, makes all the difference for me.

 

[3 Mile Stone]

It's kinda sad that no one makes a good EL34. I have to say though Bruce is right. The one time my MOD50 did pop a fuse was with the old original 250 fuse and a set of Mullard EL34 in it. Bummer. I guess it's NOS if you want reliability in the EL34 class.

 

[Doubleneck]

Glad someone posted this, I have 250Ah fuses as well. Time to change them.

What's up with this "Guitardo" dude?

 

[EWSEthan]

So, should we all be using 400mA fuses, regardless of tube type or just with EL34s?

 

[3 Mile Stone]

I put the 315 in mine, no problems at all with 5881.

 

[jmgman69]

I'm running 315s in mine with E34ls and the only problem I had was....................The fucking tone was sick

 

[EWSEthan]

Ive never changed a fuse so I guess Im still with the 250s... with Tung Sol 5881s (of course).

Maybe I should it up radio shack.

 

[bbaug14]

Ive never changed a fuse so I guess Im still with the 250s... with Tung Sol 5881s (of course).

Maybe I should it up radio shack.

I'd go and get some back ups just to have (which you should have anyway), but if you haven't had any problems yet, then I wouldn't mess with it until there is an issue. If it ain't broke....

 

[RockStarNick]

I always take back-up fuses, and actually duct-tape them to the inside of the Head box... so that I'll ALWAYS have them when I need them.

 

[EWSEthan]

If only you could duct tape a spare guitar to your head too that way you wouldnt show up to gigs without a backup! Oh, snap!

 

[bbaug14]

If only you could duct tape a spare guitar to your head too that way you wouldnt show up to gigs without a backup! Oh, snap!

 

[muudrock]

It's kinda sad that no one makes a good EL34. I have to say though Bruce is right. The one time my MOD50 did pop a fuse was with the old original 250 fuse and a set of Mullard EL34 in it. Bummer. I guess it's NOS if you want reliability in the EL34 class.

Amen! It is a shame. I remember when all the Marshall heads started shipping with 5881 back in the early 90s because of the shortage of reliable EL34 tubes. Guess everything is a cycle. I hope this doesn't mean mullets are coming back!

Anyway, because I have had a hard time finding a reliable and good sounding EL34 recently, I've tried the 5881's and 6550's. I've rediscovered some tones I had forgotten about using the 34's. I guess this shortage is not such a bad thing after all.

 

[aeroic]

It's kinda sad that no one makes a good EL34. I have to say though Bruce is right. The one time my MOD50 did pop a fuse was with the old original 250 fuse and a set of Mullard EL34 in it. Bummer. I guess it's NOS if you want reliability in the EL34 class.

Amen! It is a shame. I remember when all the Marshall heads started shipping with 5881 back in the early 90s because of the shortage of reliable EL34 tubes. Guess everything is a cycle. I hope this doesn't mean mullets are coming back!

Anyway, because I have had a hard time finding a reliable and good sounding EL34 recently, I've tried the 5881's and 6550's. I've rediscovered some tones I had forgotten about using the 34's. I guess this shortage is not such a bad thing after all.

Totally man . I love my 6550's. I really like the tones that I get w/ them in the Mod50. I am using 6550s in both my Mod50 and my VHT 2/90/2 with great results .

Eric

 

[MichaelG]

Glad someone posted this, I have 250Ah fuses as well. Time to change them.

What's up with this "Guitardo" dude?

Ditto on the 250 Ah fuses. Great thread!

To state the obvious it looks like "retardo" was very anti-manufacture-in-china. A guy is entitled to an opinion and all but geez....

 

[MichaelG]

It's kinda sad that no one makes a good EL34. I have to say though Bruce is right. The one time my MOD50 did pop a fuse was with the old original 250 fuse and a set of Mullard EL34 in it. Bummer. I guess it's NOS if you want reliability in the EL34 class.

Amen! It is a shame. I remember when all the Marshall heads started shipping with 5881 back in the early 90s because of the shortage of reliable EL34 tubes. Guess everything is a cycle. I hope this doesn't mean mullets are coming back!

Anyway, because I have had a hard time finding a reliable and good sounding EL34 recently, I've tried the 5881's and 6550's. I've rediscovered some tones I had forgotten about using the 34's. I guess this shortage is not such a bad thing after all.

Totally man . I love my 6550's. I really like the tones that I get w/ them in the Mod50. I am using 6550s in both my Mod50 and my VHT 2/90/2 with great results .

Eric

I'll be buying some 6550s REAL soon. Dude at thetubestore.com said that Tung-Sols have a harder edge to the distortion than the Sylvanias (SED winged C). Is it a really noticeable difference Eric?

 

[richedie]

The two best right noe are supposed to be the Tung Sols and SED EL34s.

250mA should be fine if you are not using EL34s and even then - it doesn't mean it will blow the fuse. I think Radio Shack only has the 315s.