Month: August 2013

Vox Cambridge 30

Great looking vintage amps powered by tiny chip amp like you might find in car stereo but don’t let that put you off. Inside you have a pair of quality Celestion speakers,  twin channels clean and valve powered drive channel,  tremolo and reverb depending on model.

Construction wise it’s pretty poor inside with a budget Hi Fi style PCB.  Partly bad luck or design on korg ‘s part these amps have an amp failure disease named after them.  Cambridgitus effects this series of amps by reducing the output level in number of ways. Either temporarily, or gradually according to temperature or permanently at some random level. The tremolo effect may or may not stop working also.

In the temperature related version of Cambridgitus the level will creep down over 15 minutes or half an hour making you think you are losing your hearing.  With the permanent version the amp is sort of stuck on a lower level.  It is all due to components in the tremolo circuit namely the optocoupler. This optocoupler controls the level of the signal through a smooth light controlled sensor. Only problem is that korg picked the wrong type in its design and they just wrong all the time some from new, a suitable replace is the increasingly hard to find device called VTL5C3.

Laney VH100R

These monster heads are well liked by metal players for their high gain and awesome volume.

Well this one came to me like a crippled kitten, working one minute and then cutting out where volume dipped completely strangling the output. The cause? Well Laney do design great amps, in terms of tone, but due the their position in the mid tier price bracket it seems to mean that compromises sometimes have to be made. I totally get that but I would prefer them to limit the number of effects sockets instead of skimping on valve socket quality.

Yes in this case and other Laney models I have seen the valve socket connection with the valve pins been problematic. In this case there are two symptoms

1. crackles, pops and rumble noise
2. virtually total cut out

I am sure this is a quality issue and not a wear issue as I regularly come across forty year old Fender and Marshall’s where a repair can be achieved just by re-tensioning the pins but these brown Laney sockets just don’t seem to play ball and replacement is the only option. However the good news is that replacement sockets are cheap and do work.

Laney VC15R

Nice Diddy combos that have a massive sound despite their tiny size.

Issues I have seen inclue:
Output transformer
cut out after a while and the culprit turns out to be the tiny output transformer. If you google round you’ll find this isn’t such an isolated problem and if you have this then you are part of a growing club of Laney owners with, or seeking, I replacement transformers.

Laney, who support their customers very well supply replacements for the price of a couple of CDs. I chose to get one from another supplier that I have used for vintage transformers with great success livinginthepast. No doubt these guys know their stuff and I was really impressed with the quick service and great sound. For me the deciding factor on the Laney was that it is an uprated transformer slightly larger than the original so hopefully it won’t fail in the future. However these amps sound so good when cranked up it’s hard to resist pushing it a bit.

Valve bases
Some Laney models do seem to have fairly low quality valve bases and this can also present itself in an amp as cutting out, crackles and noise. It’s a shame as the difference between a cheap valve base and an expensive one is probably about the price of a bag of sweets.

Amploft