Hogy wrote:
Yeah, bad wording on my part. Same specs, different manufacturers is what I meant.
Ken wouldn't deny that the Rocket was AC30 inspired, in fact if you look at his original flyer advertising the new "Liverpool Rocket Amp" it, it says as much.
The different power supply (totem pole vs. radial) makes a big difference, as does layout. Transformer, obviously.
I don't think the Rocket faces any problem. There is no amp that beats it at its own game. Certainly not any of the ones you listed.
The Songwriter is a different variation on that theme. It has become my favorite of the bunch, but a well set up Rocket is superb. It doesn't sound like an AC30 to me, and I'm a certified vintage AC30 nut. I have owned many of them, still have the two best ones I've ever heard. Between those AC30s (they are quite different from one another) and the Rocket, I have never felt redundancy.
The Rocket looks simple and is forgiving to build, but to get it to sound like Ken wanted it to isn't easy. The OT is crucial, but the tubes even more so. That amp responds to tube selection like no other. And without vintage Vox Alnicos, it isn't a Rocket.
I very much wanted to built a Rocket version under the Komet brand, but Ken wouldn't have it. He called it obsolete, because without the tubes and speakers, it would never be a Rocket.
Hogy
Interesting comment, that without vintage vox alnicos a rocket isn't a rocket.
Derek Ferwerda who owns rocket no. 2 Amanda has always played his rocket with an old ampeg VT4 4x12 cab with old celestion G12H30 prerola speakers.
Being as closed to Ken as he was I would assume if the rocket correct speaker was the vintage alnico he would use those instead of the G12H30.
You can certainly use whatever you want. A vintage G12H30 is a fantastic speaker, and my reference. I have an ancient Marshall 4x12 with G12Hs that is my set of ears, everything I ever designed or built was built on that cabinet.
Ken played his personal Rocket on a setup that consisted of two Vox cabs on top of each other. On the bottom a closed Royal Guardsman cab, Midax horn removed and opening blocked off. Fitted with original 1960s Vox Blues.
On top of that a 1963 AC30 extension cab that he converted to open back. Original speakers in it.
And he had a V4 with G12Hs there as well, he used that for the Express and Komets.
My Rockets sound the best in a 4-12 with old G12H's....even better than a 2-12 alnico cab. With the high voltage Rocket, the bottom end is fantastic in the 4-12..
Hi all,
I am having a Liverpool built and being offered a choice of 6.2k primary impedance on the OT or something lower like 5.2 or 4.4. I understand Ken used 6.2 but I am told some like a bit lower on primary impedance to cut brightness and increase grind on the Liverpool. I have to say, after reading everything I can find on the topic, I am still unsure what the impact to tone would be using a lower primary impedance, and whether I should just stick with Ken's "original recipe" of 6.2
Good question, but I can't really help you. The higher primary impedance I'm told would give the amp lower output but increased even harmonics. Whether you'd notice the decrease in output is questionable, and well what does an increase in even harmonics sound like?
Ken used this technique with the Express too. I think R.J. (or do a search on Liverpool amps) may be able to help you, I think he would have experimented with this sort of thing.
I seem to remember the higher impedance meant the amp sounded bluesy while the 5.2K value made the amp more aggressive sounding. Then again, I've heard that said about the difference between Heyboer and Pacific transformers.
Send a P.M. to R.J. I'm sure he'd be happy to tell you his observations, which would be more accurate than what I can tell you..
Good question, but I can't really help you. The higher primary impedance I'm told would give the amp lower output but increased even harmonics. Whether you'd notice the decrease in output is questionable, and well what does an increase in even harmonics sound like?
Ken used this technique with the Express too. I think R.J. (or do a search on Liverpool amps) may be able to help you, I think he would have experimented with this sort of thing.
I seem to remember the higher impedance meant the amp sounded bluesy while the 5.2K value made the amp more aggressive sounding. Then again, I've heard that said about the difference between Heyboer and Pacific transformers.
Send a P.M. to R.J. I'm sure he'd be happy to tell you his observations, which would be more accurate than what I can tell you..
I seem to recall some threads about the old 5k2 vs 6k6 OTs in the Liverpool and what was more authentic (or more common in original TWs).
My Liverpool has a Toneslut OT with both taps. I think the threads seem to favour 6k6 being the more authentic. I had gotten quite attached to my 'pool with the 5k2. It was indeed more aggressive in the sense that it had more bite. It seemed to make it a bit brighter and bolder with more headroom (which I seemed to lose easily with my VVR turned down already). The 6K6 was creamier it seems to me. I felt I needed that extra 5k2 bite at the time for my band... I think I will revisit the 6K6 again soon for fun.
Anyways, I think I do remember the discussions at the time favouring 6k6 as the more common primary impedance of both the Express and Liverpool.
Basically, I'm seconding what Mark just said.
I'm interested in your thoughts about VVR. I will be building an Express this year and I wanted to use VVR to drop volume of the Express as they are so loud.
In your opinion what are the strengths and weaknesses of VVR. I heard they are pretty good for dropping the volume of an amp to a third of it's normal volume without coloration.
Markee, let's us know how you got on with your amp and what you decided to go with. All the best with that.
I had my Pacific OT's wound from the TW spec sheet but had them add a 5.2K tap. I have an Express here with that Pacific OT and a switch between the 5.2K and 6.6K taps. I have to say that the difference is really subtle to my ears... I'll play with that a bit later and listen again and report back...
To my ears, output tubes and actual output tranny selection make a much greater difference than the difference I hear in the impedance taps.
As an experiment try setting the impedance switch up or down a notch and see if you can hear anything in the tone that is distinguishable beyond the volume change. Gerald Weber once stated that you can be off by as much as 100% in impedance matching your OT to the load. Not that he knows everything but the general idea holds up in my experience - proceed with caution just the same. Not enough load on your OT and it will become extremely quiet in a permanent fashion.
The difference between 6.6K and 5.2K is dramatic. IMHO the aggressive nature of a 5.2K in an Express takes away some of the elasticity of the tone. I prefer 6.6K in both the Express and Liverpool. The Liverpool with the right guitar can go from total saturation to bell like cleans with the guitar volume knob.
RJ Guitars wrote:I had my Pacific OT's wound from the TW spec sheet but had them add a 5.2K tap. I have an Express here with that Pacific OT and a switch between the 5.2K and 6.6K taps. I have to say that the difference is really subtle to my ears...
Allynmey wrote:The difference between 6.6K and 5.2K is dramatic. IMHO the aggressive nature of a 5.2K in an Express takes away some of the elasticity of the tone. I prefer 6.6K in both the Express and Liverpool.
How can there be such a difference of opinion? The same transformer with switched windings would seem to isolate the impedance effect pretty well.
It was the response difference that was dramatic. It had to do with how the amp reacted by adjusting the guitars volume. It was like the guitar pot had a different taper by the feel of it. Try them side by side and see.
