The Express uses a 300mA power transformer with matching OT for 50 watts.
There's info in the net of TW Express 30-35W with OT 6.6K, but you mentioned 50W. Why? Could you explain, please?
Also, why is necessary to provide such a big amount 300mA?
Thanks in advance.
Regards,
Adam
You primary impedance on your OT is not 3.3K or 3.4K always for EL34. Look at you data sheets. Many factors go into determining what will work and what you desire. Your reflected impedance is tied to Pout as well as voltages. For instance, old Baldwin Organs with around 300 VDC on the Plates normally had a 10,000K primary with 6V6Gt. Raise the voltages to a 5E3 Deluxe and you find 8K. Raise it more like a Blackface Deluxe and you are looking at 6k6 primary. Then look at the KT66 GEC data sheet. Some build it with a 4K like a Bassman, but to me the tube sounds more Fendery with a tad more bottom girth. Raise it to a 6k6 primary and you get a nice JTM45 with stronger upper mids. Even with the same values. These changes are not nothing compared to changing a speaker load from a 16 ohm tap to an 8 ohm tap.
Here we are speaking of selection for tone or overdrive as well as NFB which which plays a role. There are books, not paragraphs written on the subject. Experimentation is the best to gain understanding. Do not think because your clean out is less this amp will be quieter. It is loud as sh*t and needs to be played this way. Get lower SPL speakers. 93 DB if possible.
The reason for the seeming high MA on the HT is the Wreck is prone to oscillation and if you build it as I posted you chances of success will greatly improve. Edcor has a PT that is really good for the build and doesn't break the bank. A lot of guys who build will get the minimum Power Transformer that is required. If you are a blues guy, you may like this, but the Wreck will not. This amp cannot sag, trust me. I built a bomb with one. Changed the PT and changed a few resistors and it woke up.
Dummyload's and others advice is spot on from my experience. I have never built one, even a preamp version, that sounded right at fire up. They have a enormous fill, but can easily be flat and sterile. This is normally a oscillation you cannot hear causing it. It cancels phase and hopefully you have a Oscilloscope to find this. If not, it can take days to weeks and still you may not know where it is. Do not try a small chassis. I have never built one that sounded correct, except the replica, in a smaller than a 8 x 19 x 2 aluminum, heavy aluminum. The Transformer needs this.
I know the feeling about Reverb, but this is really not a verb amp. I have done it, but mine does not have it. I did install a Mosfet based loop lifted from a Dirty Shirley Freidman, but I have also successfully added a Metro Loop too. SS loops. To all you tube guys, your pedals have ss components, however I do like tube color in low gain loops. Mine is bone stock as built in the PDF I posted. No loop and I will use a Klon at unity volume. The amp likes Delay in front and doesn't like chorus. A buffer is nice and a tone bender with the Germanium Transistors are nice with single coils. Buckers are too over the top with any fuzz.
The gluing together of the mica caps is no joke in the Express. Since Ken Fisher was well above me in knowledge, I have no idea why or how he thought of it. I do know what it does, but I do not understand how it stops oscillation.
I have seen 3 in real life. All are done this way. One thing I found beneficial is to used sealed Pots. I prefer old Allen Bradleys, but the made in Mexico Honeywells are nice as well. PEC are as well. Simply put, they shield. Yes, I have seen Alpha pots used, but I have also heard a lot of wrecks sound like distortion boxes too.
Look here and listen to a real one. The cleaner side with the guitar knob is really nice and is what I try to achieve. Rolling back enough to stop preamp clipping and rolling in to get it. Do not pump V1 with a boost unless you have a real compressor, not a stomp box compressor. Listen to Glen's amp on youtube I linked to. This is what a Wreck is. I have one because of the mystic, but I have never used it to play a gig. I play low gain fenders and Marshall. But I am more of a clean player.
Not saying it is not a fun amp. When I am home ALONE playing old Whitesnake through a 1960 Marshall cab sounds great.
Good luck!
https://www.youtube.com/watch?v=Y2_12Ler9B8
Topic: TW Express with reverb (Read 6390 times)