Trace Elliot V4 help !!

[Sean B]

I own a V4 15 inch combo (later version with compressor) last weekend a power tube decided to go and naturally one of the power tube fuses blew. SO... replaced the power tubes, replaced the blown fuse, checked the main fuses (one was blown) replaced it. Now I am unable to get any sound. All of the pre amp tubes are good. The EM 84 tube is not glowing it's usual greenish blue. My question is would a faulty EM 84 tube cause the lack of sound, or is it not it's usual colour because of another issue. I have checked the speaker connections and all is good as are instrument leads etc. I also noticed the main fuse I replaced should be a T1.6 AH, but was sold a T1.6 AL and was told it's the same. The fuses are not blowing, but I still have absolutely no sound. Any help would be received with much thanks. I hope someone can help, taking it to a tech is my last resort

 

[B-string]

You probably have a HV (high voltage) fuse inside the amp. These would not be external on the amp due to safety certification requirements.

 

[Sean B]

Thanks for the speedy response, looks like only a tech can fix that for me.

 

[Mitchthebassplayer]

I've only had one type of similar issue with my V6 head, but in my case, the fuses kept blowing. I eventually realized the output transformer was shot and it had to be replaced (several hundred $ later)....if I remember correctly, my V6 has 3 fuses....2 were obvious, and one was a bit more hidden. good luck!

 

[B-string]

The chassis would have to be pulled out, that exposes the person to dangerous voltages. It is not hard to replace but doing it safely is a real concern. Should not cost you much at all to have a shop do it.

 

[Sean B]

Thanks mate, will have a look for a possible third fuse, called Trace today and although they were very friendly, they couldn't really help me.

 

[Sean B]

Thanks B-string..

 

[Mitchthebassplayer]

HT1 and HT2 should be visible on the back panel but the third (mains) fuse is in the bottom of the AC plug in thing....def no chassis removing necessary unless your combo is some kind of radical design I'm not familiar with....

 

[B-string]

"The EM 84 tube is not glowing it's usual greenish blue." This bit here says high voltage missing (or other support components have blown) to an old amp tech. Are you sure those are not EL34 tubes?

 

[Mitchthebassplayer]

the V-type amps shouldn't be running on either of those tubes. a V4 should have 4 x 12AX7s and 4 KT88s or 6550s in the power section

 

[Sean B]

It's the mark 2 version with 4 kt88, 7 12ax7 and 1 EM84, not many made, have never seen one stateside (lived in Chicago for many years) will check for third fuse now....Many thanks for your help

 

[B-string]

KT88/6550 was for US models. Across the pond the schematics specify EL34s that I could locate.

 

[Mitchthebassplayer]

It's the mark 2 version with 4 kt88, 7 12ax7 and 1 EM84, not many made, have never seen one stateside (lived in Chicago for many years) will check for third fuse now....Many thanks for your help

wait your V4 has SEVEN 12AX7s??? Jesus....ok so the EM84 is a rectifier tube....interesting....my V6 uses a solid state rectifier....you probably need a new one then if the amp is turning on then the fuses are fine.

 

[B-string]

EM84 tuning indicator used for a "VU meter"? Interesting.

 

[Mitchthebassplayer]

KT88/6550 was for US models. Across the pond the schematics specify EL34s that I could locate.

really? you sure about that schematic? EL34s are so much weaker than KT88s or 6550s and are usually found in guitar amps. You would need almost double the number of 34s to match the power of the 88s (6550s)....I think I saw a Mesa 400+ once full of 34s and it had like 12 of them in there....

 

[B-string]

EM84 is NOT a rectifier tube Invalid Link Removed

Here is the schematic I found http://www.google.com/imgres?imgurl...TOMUeH0I4W4qAG3y4GYCA&ved=0CFEQ9QEwBQ&dur=848.
Marshall spec'ed the same on their imports with some 6L6GC US/EL34 Europe.

 

[Sean B]

Definitely Kt88/ 6550, there is another fuse in there, just checked under the mains socket thingy says T3.15 AH, must be inside somewhere....

 

[Sean B]

Would be great if new EM84 tube would fix problem. They are cheap, would a faulty one cause no sound ?

 

[Mitchthebassplayer]

EM84 is NOT a rectifier tube Invalid Link Removed

that link doesn't really show me anything but I just looked up some other stuff on the EM84....what a crazy tube! I've never seen that before....what is it actually doing? It looks VERY similar to the rectifier tubes in other amps I have but I guess it isn't one....

 

[B-string]

I have doubts.