VHT Special 6 Ultra Valve Amp
I am currently working on a VHT Special 6 Ultra Amp. This is an amp head and this one has a 1 x 12 Goodmans greenback equipped close backed cabinet. This amp is only 5 watts.
It makes a nice little practice/ bedroom/ studio amp where you can sound as if you playing through a fully cranked up Marshall 200 watt stack..great fun. These amps are very competitively priced too as they are made in China ( somehow that just does not sound right but it has the promise of being a good amp company)
For those of you that dont know VHT valve /tube amps, check out – http://vhtamp.com/
VHT design the amps in the USA and they are hand wired in China. They are low cost and offer a lot of flexibility in tome range. The owner of this amp has asked me to improve what he considers a very thin sound.
I played through it and with the Laney cabinet and did notice lack of bass and middle tones. To ensure an apples to apples comparison, I played my silverface Fender Deluxe reverb and then connected the VHT to the speaker in my Deluxe Reverb and they was a marked difference in the lack of bass in the VHT.
I have studied the circuitry of the VHT and it is basically a “hot rodded” Fender Champ. It does have an extra double triode 12AX7 for that extra gain which is needed to get the overdrive sound. The line up is 2 x 12AX7’s and one 6V6GT for the output which can be switched into triode mode and this reduces the power to 2.5 watts. I cannot see the point of this feature on such a low power amp. Disappointingly, it uses solid state rectifiers so there is no true ” sag” from a tube rectifierto help the sound when it is cranked up.
The amp has two channels one is clean, and the other is where you get to play with overdrive of the 12AX7’s. One nice feature is a send and return for effects.
So I have some ideas for the modifications to improve the tone. Also the clean channel is still a bit dirty so I am going to reduce the gain a bit on the 12AX7 and this will make the cleaner clean channel.
I will take pictures of the modifications so when i write about how thi worked out you can see exactly what to do to replicate the results I get.
Watch out for the next post which details the modifications . Part 3 of the Fender Deluxe Reverb restoration will come after I have modified this cute little VHT, The owner needs it back!
