I want a Science Amplifier

[BetterOffShred]

I suppose it depends on the topology of the amp itself, but I find 6L6's to be tighter bass and slightly less pronounced mids, which is where that Marshall roar comes from partially, that EL34 mid range. All my amps are 6L6 platforms..

As far as changing to KT's.. I'd inquire with the builder, but I'm sure he uses robust iron, but as I recall the filament current on most KT series tubes is fairly substantial. As long as your heater taps are rated for enough current you should be good. Most KT/6L6/EL34 tubes sound good around 425-475 volts. Once again I don't know the topology or DC voltages of the amp, but I'd sure give it a try.

[Nateispro]

I suppose it depends on the topology of the amp itself, but I find 6L6's to be tighter bass and slightly less pronounced mids, which is where that Marshall roar comes from partially, that EL34 mid range. All my amps are 6L6 platforms..

As far as changing to KT's.. I'd inquire with the builder, but I'm sure he uses robust iron, but as I recall the filament current on most KT series tubes is fairly substantial. As long as your heater taps are rated for enough current you should be good. Most KT/6L6/EL34 tubes sound good around 425-475 volts. Once again I don't know the topology or DC voltages of the amp, but I'd sure give it a try.

Alex said I should be fine to roll any of those tubes in a Hellhawk. I'm thinking of going with the 6CA7's or KT77's. I have no experience with either though

[BetterOffShred]

6551's are dope too. Throw 77s in there and go forth and crush. You won't be sorry.

[humandingus]

i've been using kt77's for the past couple years and i've been very happy with them!

[waltdogg]

6551s are just mil spec 6L6s

[waltdogg]

also. kt77s are in the el34 family. 6ca7s are in the 6L6 family. anything larger like 7027s, kt88s, 6550s, etc. you’re in the servo tube damoly.

[BetterOffShred]

I meant 6550s, my apologies. They do pull nearly twice the heater current as a 6L6 though looking at my tube charts. At least based on the GE 6L6..

They are typically a shorter package than the kinkless variety, lending themselves to numerous applications

Let us know what you do, I'm curious.

[waltdogg]

6550s are scary awesome.

i've NEVER had to change a set of them EVER. my original sunn model t had some nos sylvania 6550s. those shits fell right out of their sockets when i dropped the amp upside down (don't ask), tubes didn't shatter, reseated the tubes and it powered right up. i bought a used svt-vr with it's original sovtek 6550s, no bias or volume problems at all. sovtek makes reliable tubes. so does jj. but in different ways. sovteks are mostly mil spec. jjs are built to old tesla specifications and on their old machinery. jjs can be hit or miss, but you can chalk that up to quality control not being what it used to be 50 years ago. that being said, you get a good set of jjs. they'll give you full power, no problems, for years. then one day, one will die with no warning.

[BetterOffShred]

Yeah the 70s variety Sunn iron is crazy robust. Most of those amps all had 6550s factory. Probably got a huge truck load of them

[whoismarykelly]

Yeah the 70s variety Sunn iron is crazy robust. Most of those amps all had 6550s factory. Probably got a huge truck load of them

Most of those designs with the exception of the Model T are Dynaco Hi Fi amplifiers adapted just barely for guitar and bass. Its not that those transformers are any more robust than the other amps of the era. They were just designed exactly for how Sunn used them and Sunn was just following someone else's lead.

On the Science front I don't think Alex is using a different PT depending on what tubes you order so as long as the pinouts work, you can probably drop anything into a Science and bias it up as long as the bias range is fitting.

[whoismarykelly]

After having the new Decolonizer MKII 100W on hand for a bit I'm really enjoying the different tones compared to the MKI. Major difference is the switchable OD control which makes the amp basically have three channels. Unlike the MKI though, the OD boost just adds more gain without changing the tone. The MKI has two dramatically different tones on the + and ++ modes and the ++ mode is a really aggressive and cutting tone. The MKII is more on the + side and is warmer than the MKI's + mode. It can almost be dark at times depending on your guitar. I find myself cutting bass and cranking treble a lot of the time which is the total opposite of how I run the MKI, especially in the studio. I may end up swapping in 6L6s or another tube with a bit more treble response to see how the amp changes.

[BetterOffShred]

Yeah the 70s variety Sunn iron is crazy robust. Most of those amps all had 6550s factory. Probably got a huge truck load of them

Most of those designs with the exception of the Model T are Dynaco Hi Fi amplifiers adapted just barely for guitar and bass. Its not that those transformers are any more robust than the other amps of the era. They were just designed exactly for how Sunn used them and Sunn was just following someone else's lead.

You can still get Dynaco transformers from Triode, and though they are spendy they have good specs for big tubes. 2x6.3V@5A and a 5V@4A, and 720VCT.. I consider that robust. Obviously pushing a quad of 6550's you need some power, but even their twin tube designs like the the sorado and 200S etc still were capable of 70 or more watts.

I used Classictone transformers in my most recent (5 watts ) build and they are good specs too. Their big power project transformers are pretty dope and include relay taps and taps for running heaters on DC.

[whoismarykelly]

I've used Classictone in an amp build and they were by far my favorite transformers I've used for quality and cost. I don't know if the new Science iron is made by Magnetic Components but the transformers in my Decolonizer MKI are the big power project set I believe. I think all the old amps had different makes and models though. My Mother has a different brand and I think my friend's Hellhawk has Heyboer iron.

[waltdogg]

I got all Classictone in mine

[BetterOffShred]

All of the iron discussed on this page is certainly quality. I dig heyboer too for sure, but for my future builds they are all based around Classictone. That big power project transformer is just too flexible for the money. And their dimensional drawings are top notch.

I've had a 2204 planned for about 10 years