Trainwreck Preamp Pedal..built it.Sounds good. Has one mega problem...need help!

[zambo]

@ Aron..sorry man, I dont have the schematic for the Dirty little monster. All I know is what I have read which was not as informative as what you posted. I was just going to try and put an express pre infront of an el34 or 6l6 power amp. That should give me the stated 10 watt output more or less. I think if the eq is built right then the rest will fall in with some common sense and some ear tuning. I will probably start with an AX84 P1 Extreme kit and go for it from there. I know the iron wont be right but...whatever...I will make a better one as money permits. I dont think it would have stopped KF from building with whatever is around. I am thinking the spirit of buildind says...take a bunch of leftovers and tune it to sound phenominal!

Thanks for your kind words btw! Cheers, G

[aron]

Greg,

I played the first Train Wreck - the prototype one that was made from Fender guts. It's great! Very Fusion-type sound and I really wish I had it.
Anyway, my current modded Fender is doing the job for me. I made a JFET version of the Express a long time ago and then there is the Shaka Express too.

Anyway, your playing is great and so is your pedal!!!

Aron

[Brymus]

Greg,

I played the first Train Wreck - the prototype one that was made from Fender guts. It's great! Very Fusion-type sound and I really wish I had it.
Anyway, my current modded Fender is doing the job for me. I made a JFET version of the Express a long time ago and then there is the Shaka Express too.

Anyway, your playing is great and so is your pedal!!!

Aron

Aron I have somewhere a schematic that is supposed to be the DLM that Ken Fisher designed.
I remember all the hype about it,where its at now IDK.
If I can find it I will PM you.
But you should be able to find it at the amp garage or SEwatt.com.

This guy likes building TW type amps outa EVJ platforms. http://dnator.50webs.com/gimlet.html

[DougH]

I was thinking it might be fun to build a preamp like this, run it at 200-250v, and add a bypass switch for the "half PI" stage. Then I could bypass that stage and plug it directly into the fx loop return of my 100 watter to drive that PI and power stage. It would also give you the option of using the half-PI for the sound and amplifying it with a SS power stage like Greg did in the video. Last night it occurred to me that I could use one of my "church sound system dumpster dive" amps for power amplification for it.

This should do the trick:

[sst4270]

All,

My understanding is the DLM is located in Hawaii.

This thread at TAG will provide pretty much all the background you require regarding the DLM and its owner "wreckboy".
Oh! Including a photograph of the DLM along with a few other original TW's that he owns.

Enjoy: http://ampgarage.com/forum/viewtopic.php?t=3490&highlight=

Regards,

Steve

[zambo]

@ Doug, If you make that stage bypassable, you could hook a 1m volume knob up to it and use it as a volume boost/extra gain stage and it would be a real nice feature at that point. And when you are using it as the psuedo pi stage just run it at max vol. Just a thought. I love the volume boost though. oh ps.....SCORE on the church find....lucky!

@sst40. Thanks! Thats a good thread and where i got the info I have. There is a short vid on you tube as well under wreckboy. I dont know what he is using but it sounds sweet!

[zambo]

Also- I am thinking I will start the new project that is a parallell distortion with a hotbox on one side and a trainwreck on the other running simultaneousley. And the name........The Box Wrecker! So i will probably start a development thread with that title. Anyone interested in this project or should I just post random updates? I am sure I will need a ton of help

[ChrisA]

I often have wondered why most tube amps don't use an input cap, when if there was a significant failure you possibly could have the full HT on the grid (not likely with a preamp, but then, not 100% UNlikely, either). 

I have an amp that failed this way. The cathode ground connection on the first stage came loose and the grid floated up to around 100-200V (whatever the plate voltage was). The input jack ground was isolated from the chassis too. So if there had not been an isolation cap on the input, the jack would not have shorted the voltage to chassis ground and that voltage would have been on the input cable and guitar. I have had problems with scratchy guitar pots with some amps so I put input caps on them to fix that. I'll probably start adding those on all amps now.

The input cap mmakes some sense but  I think if you are very concerned about safety a few diodes in series with one (or half of them) reversed could be used to clamp the voltage to some safe level.  If there was ever a high voltage on the jack then the diode would conduct and the fuse would blow, shutting off B+.    I think the setup where you have a diode that normally never conducts and a fuse that blows if it does is called a "crowbar".    Using a GFCI  outlet would make it very safe

[aron]

>My understanding is the DLM is located in Hawaii.

Yeah, that's my friend. I played most of the Train Wrecks he has except for the Liverpool versions. I still like the prototype first Train Wreck - to me it sounds bluesy and has a "fusion-like" sound.
The Express is more than I can handle at my stage of playing. That's another thing, Wreckboy is an awesome player. Honestly, anything he plays sounds good and I've been listening to him since I was in middle school.
Fantastic player!

[zambo]

@aron - thats very cool you got to play all of them. I want an express in the worst kind of way! Wreckboy is the man! I only heard like 50 seconds on youtube but it was a very impressive 50 seconds. Awesome sounding rig whichever one he was playing.....

[markeebee]

Also- I am thinking I will start the new project that is a parallell distortion with a hotbox on one side and a trainwreck on the other running simultaneousley. And the name........The Box Wrecker! So i will probably start a development thread with that title. Anyone interested in this project or should I just post random updates? I am sure I will need a ton of help

I would be hugely keen on a development thread for this, if you can find the time. I think all of your stuff is kinda inspirational.

One thing, off topic. "Chicken" is slang in the UK for child pr0n. Your sig.....

[zambo]

WOW! Thanks for the heads up! Hear its still a bird! Still changing it though!

[DougH]

The Express is more than I can handle at my stage of playing.

That's kind of the impression I got after experimenting with some wreck ideas a few years ago. The clips I hear/see seem to reinforce that too. Too much gain for me when the guitar volume is maxed.

[zambo]

ok so i was having a problem with bass lag or to much compression with this preamp. I thought it was to low a voltage at 45v so i upped it to 90v but still had the same thing happening. I removed the cathode bypass caps and viola..its gone. The cathode bypass caps basicly pull frequency through and amplify it more right? So a bigger cap amplifies more of the spectrum vs a smaller ones that amplify more highs....is that the basic premise of them? Why do they cause that lag in sound??

[Cliff Schecht]

The Express is a fun amp to play. I've built a few from scratch and really dig the amount of cut this amp gets live and at practice. It'll punish you for playing sloppy yes, but isn't that all the better of an excuse to practice?

[zambo]

Have you ever built one with less wattage and or single ended?

[radio]

@DougH:

Am I allowed a uneducated question? 

What is sonically the specificity of a trainwreck,I never played one?

Thanks for any response ! Jean-Marie

[Brymus]

Here is a clip of a TW Express by the guy who probably has the most of them on You Tube http://www.youtube.com/watch?v=mL75YzhAcJ4&feature=related

At Zambo yeah that's basically it.
Keep in mind the cathode resistor helps determine the amount impact the cathode cap has.
The larger the resistor the more you will hear the difference.

I always think in terms of 1k5 and 22uf is pretty neutral biased and the full guitar range boosted.
2k7 .68uf typical Marshall input stage is biased colder but the upper end is boosted alot more due to the cap and resistor.
I dont know what would cause the bass to lag behind the rest of the sound.

[radio]

Thanks for the inlightment!

Somewhere between SRV and fusion,I really like that.

Thanks JM 

[dorrisant]

Do you have any gutshots?