trinityamps.com

Would it be possible to install a tube rectifier instead of the solid state rectifier? I have been looking for a decent sounding single ended amp and the Tramp looks like it might fit the bill. I would however like a tube rectifier and choke. Has anyone experimented with this on the Tramp?

Thanks,

Dan

A tube rectifier on a Class A amp like the Tramp will do absolutely nothing. In Class A amps compared to Class A/B the current draw of the amp is constant. With this your not going to get the desired sag associated with tube rectos.

If you want to put a big power resistor right after the SS recto. This will simulate a tube recto.
If you like the "browned" out sound of the tube recto just turn down the VRM (Power Level) The Tramp gets a lot of different tones!


Why do you want to add a choke? Again very small difference between a choke and a resistive element. I have A/Bed them and can tell you the difference is very small especially in an amp like this.

_________________
http://pdfelectronics.com

Thanks for the reply. Now I remembering reading somewhere about Class A not needing a tube rectifier and choke. What size and value of the power resistor would you recommend? There already is a 5W 100 Ohm power resistor after the junction of the 2 UF4007s.

I have another question regarding the power transformer. I am building this amp from scratch and already have a BBQ PT rated at either 600V or 660V from the secondary but only has 80 ma. The PT spec'd in the Tramp is 630V with 120ma. I also have a Fender Champ PT which is rated at 650V at 70ma. Would either of these PTs work or should I be looking at maybe a Hammond 272DX - 600V at 125ma.

Thanks,

Dan

In other words it will also do nothing for the amp, apart from a little loss in power level. The 100 ohm resistor that's in there is to filter out ripple. Single-ended amps need more filtering than PP amps, which tend to self-cancel a lot of ripple.


+1


+1 again. A choke is a complete waste of money and time with this amp, which I designed *not* to need a choke.


The Champ PT would *not* be suitable. Fender transformers are cheap, nasty and badly under-rated for the job, plus the Tramp is intended to be able to run bigger power tubes, such as 6L6s, KT66s or EL34s. The BBQ would probably be OK for 6V6 power tubes. And the Hammond looks like the voltage is too low. So I recommend buying and using the correct transformers from Trinity. A lot of time and effort (as well as expense) was put into getting these transformers just right for the design and the tones we were trying to get. The other components are more generic.

_________________
Great tones come in small glass jars!

Well, I finally finished my Tramp build and was getting low volume and no response out of the volume control. Traced down the problem to an error on the layout - pins 1 and 6 on V1 were reversed. Now the amp works and sounds pretty good. I used the Hammond PT and am getting 307 VAC from the secondaries which is only 8 volts lower than what was shown on the schematic. My B+ voltages are 392V VDC from a 6V6 and 378 VDC using a 6L6 with the VRM at max. The 6L6 gives a better, fuller sound than the 6V6. All of the other voltages are about 2 to 5% lower than what is posted on the schematic so I am confident that the Hammond PT works with this amp. I also am using the BBQ 15 watt SE OT and am happy with the sound. Someday I might try the Trinity transformers if they were available separately at a good price. I priced them out at Heyboer, using the specs on the schematic, and they wanted almost $200 for both! The reason I did not purchase the whole kit was that I already had chassis, board material, tubes, and all of the components already on hand.

My next task, besides some minor tweaking to get the best tone, is to decide which speaker to use. The Tramp sounds great through my 12" Jensen P12Q alnico speaker. I am also going to hook up my BBQ's 10" silver pup and blue dog (both Alnicos) to see how it sounds. I have an old Yamaha 12" ceramic from an old Bass Amp but the Tramp sounds too thin and sterile. I realize there has been a lot of discussion on the best speaker to use with this amp and from what I gather, it is matter of personal choice so I will continue to experiment.

Dan

Dan, check your layout against the current one posted please . We had this problem some time ago but it was rectified.

Congrats on your build. As mentioned, a lot of effort went into the iron for this amp, and the result is quite amazing. I was shocked how much tonal difference 1/4" more laminations on the OT made. These are exclusive to Trinity though.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps