madlee wrote:also, perhaps sealing up the back, and making vents in the top, which would allow the heat to escape and pull in cool air from the front.

the fan system that Traynor used one the YBA-1A, YBA-3, and YBA-3A worked well.

the plan for the amp i'm designing is that it's all sealed, except on each side there's a fan (desktop computer style) pulling air in, and then two on the top blowing air out. knob on the front to set the fan speed. that's the plan for that. i'm thinking maybe 600V on the plates, and 11 tubes total (6 output tubes) so fans will be pretty important.

scott wrote:the fan system that Traynor used one the YBA-1A, YBA-3, and YBA-3A worked well.

the plan for the amp i'm designing is that it's all sealed, except on each side there's a fan (desktop computer style) pulling air in, and then two on the top blowing air out. knob on the front to set the fan speed. that's the plan for that. i'm thinking maybe 600V on the plates, and 11 tubes total (6 output tubes) so fans will be pretty important.

6 power tubes! so the fans likely won't need to be quiet!

a suggestion: put an air filter on the fans that pull air in. all that dust will just go all over your components.

A couple quick comments. My YBA-3 is set up with 6550's and a master volume mod and some other mods (most of the velvet black mods I think). I almost always have the master volume at 8-10. It just doesn't sound that great to my ears at lower settings. As far as distortion goes, it will certainly do this on it's own, but the amp will be so loud as to be painful. If you don't believe me, come to a Chrome Robes show. Har har. I think you'll probably want to go the power attenuator route or put a distortion pedal in front.

This has just arrived today, and I can't get the sucker working. The amp came with a cabinet, so I am using that speaker cab since I don't have another one.

I think I have everything plugged in correctly. I turn on A/C switch on the back and the tubes light up, the fan works. With the standby switch up the red standby light comes on, I pull the standby switch down and the other "operate" lightbulb doesn't come on. And no sound.

I have the phono lead going from the "speaker" output on the back into the speaker cabinet.

Spoke to the guy who sold me it and he thinks it might be the fuse, but it worked fine when he tested it before posting.

Help please.

As this is an old Traynor I'm sure the cavalry will be along with lots of good information for you soon, but some things I would check in the meantime:

-do you have any sound at all from the amp, ie. if you crank it up is it dead silent or do you hear some hiss?

-are you confident the speaker cord is good? if you have something you can swap it out with that would be worth trying.

-do you have any way to eliminate the speaker box as the source of the problem? If you don't have another cab to try that head with, do you have another head to try that cab with?

-check the fuses. If it lights up it probably is not the AC fuse, but many amps have another set of fuses, mine are labeled 'speaker fuse'. I don't know if you'll have this on an old Traynor or not.

projectMalamute wrote:As this is an old Traynor I'm sure the cavalry will be along with lots of good information for you soon, but some things I would check in the meantime:

-do you have any sound at all from the amp, ie. if you crank it up is it dead silent or do you hear some hiss?

-are you confident the speaker cord is good? if you have something you can swap it out with that would be worth trying.

-do you have any way to eliminate the speaker box as the source of the problem? If you don't have another cab to try that head with, do you have another head to try that cab with?

-check the fuses. If it lights up it probably is not the AC fuse, but many amps have another set of fuses, mine are labeled 'speaker fuse'. I don't know if you'll have this on an old Traynor or not.

Thanks.

Have tried a few of these.

When I switch from standby on to off (from red light to nothing) there is a low hum that comes out of the speaker. Nothing else happens if i turn up the volume.

Have swapped over speaker cord with a instrument lead (same jacks) and still get nothing.

I don't have another cab, but I do have another amp head, but it is buried under a ton of junk in a storage cupboard and it is not very reliable. Is there any other way to check the speaker.

The guy I bought it off, originally bought it off a friend of his who is an amp tech. He has spoken to the amp tech and said it has probably been knocked in transit, and the standby switch may be faulty. He suggested taking it to a local tech and asking them to measure the input and output to the standby switch. He says the green operate light should come on after switching the standby switch.

Alternate testing procedure for the cab:

You can plug a cord in to the speaker box and touch a 9V battery to the other end. You should here a pop and all the speakers will move, hopefully in the same direction. This is also a good way to check things if you suspect a speaker is wired out of phase, it will move in the opposite direction of the others.

projectMalamute wrote:Alternate testing procedure for the cab:

You can plug a cord in to the speaker box and touch a 9V battery to the other end. You should here a pop and all the speakers will move, hopefully in the same direction. This is also a good way to check things if you suspect a speaker is wired out of phase, it will move in the opposite direction of the others.

Thanks, that's a great tip.

Yep, it made a pop.

are you using the "speaker" output jack as opposed to the "Ext speaker" jack? You should use the "speaker" jack and not the "ext speaker" jack.

if you're getting a hum sound out of the amp when it's not in standby, that probably just means that the lightbulb for the "operate" light is burnt out or even just loose. unscrew the green gem from the front of the amp and you can take out the lightbulb that's behind it... take a look at the bulb and see if it shows signs of being burnt out.

even if the guy did a horrible job with packing the amp, even then there's still no reasonable way the standby switch would somehow be affected by transit. that sounds absurd.

have you taken off the back panel and had a look at all the tubes? are they all seated properly and lighting up a bit even when the amp's in standby? you might want to try removing and re-seating all the tubes, as one of them could very easily have been jostled about during transit. sometimes it's as simple as pulling them out and putting them back in. do that with the power off.

Thanks Scott.

Yes, I'm using the speaker output.

I'm getting a hum sound out of the amp when standby is both on and off. When the standby is off I think there is a low hum through the cab too.

I've taken out the power tubes and put them back in firmly (they had come out a little), they are all lighting up both in standby and not.

I have taken the covers off the preamp tubes and they were not lighting up, are they supposed to? Can you pull them out just like the power tubes, they seemed to be fixed firmly in and I didn't want to yank them out.

I have taken the cover off the operate light, the bulb seems fine from the front but it would not easily come out to check behind it.

Still no sound. So frustrating.

Any more ideas?


Oh, and when the amp was delivered, there was no packaging at all. It did some by courier though.