Tiny Terror Hard Wired repair / resistor

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mjbmjb
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Tiny Terror Hard Wired repair / resistor

Post by mjbmjb »

Hi, my TTHW had some warranty work done and came back with an extra 10 watt sand cast resistor...... see attachments.

It seems to sound a bit off to me. Could it be this extra resistor and, from the pic, can anyone enlighten me as to why it is there?

Mike
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selloutrr
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Re: Tiny Terror Hard Wired repair / resistor

Post by selloutrr »

can you identify where exactly it terminates?
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mjbmjb
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Re: Tiny Terror Hard Wired repair / resistor

Post by mjbmjb »

I'm not good with circuits....it seems to sit right between the power sockets.
mjbmjb
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Re: Tiny Terror Hard Wired repair / resistor

Post by mjbmjb »

here is another pic... the red wire going down goes directly to the power tube and terminates there.
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rp
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Re: Tiny Terror Hard Wired repair / resistor

Post by rp »

Don't know about the resistor, but I think it's amazing to see a modern production amp from a big corporation looking like it was built in 1938. Friggin' awesome!
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selloutrr
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Re: Tiny Terror Hard Wired repair / resistor

Post by selloutrr »

mjbmjb wrote:Hi, my TTHW had some warranty work done and came back with an extra 10 watt sand cast resistor...... see attachments.

It seems to sound a bit off to me. Could it be this extra resistor and, from the pic, can anyone enlighten me as to why it is there?

Mike
It's probably thier to correct the problem that caused you to have to send it in for a warranty repair ;)

It might not sound off it might sound right, you are just used the amp sounding the way it did before it was running correctly?

I can't tell where the resistor terminated from the pics.
- It looks like your amp has several resistors the Promo Amp in the first pick doesn't have. Probably used a different transformer or values, in your amp. The resistors adjust voltages.

hope it helps.

A thought - not knowing what sent your amp to the bench to be fixed, is it possible your tubes took a hit and / or where replaced? that would alter the sound from the time you last heard it.
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Cliff Schecht
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Re: Tiny Terror Hard Wired repair / resistor

Post by Cliff Schecht »

Being the fact that it is a massive 470 Ohm resistor paralleled by a large cap, I think that resistor is your power tube cathode resistor. It looks like the repair guy upped the wattage so you won't ever run into problems with that particular resistor dissipating too much power and opening.
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guitarmike2107
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Re: Tiny Terror Hard Wired repair / resistor

Post by guitarmike2107 »

470ohm is too big for a bias resistor on a 2 x EL84 amp,

My bet is that they have replaced a wire link to the screens with this resistor, lowering the screen voltage which will help your valves run a bit happier and last a little longer too.
The only difference you should notice is very slightly reduced clean headroom from the power section.
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Structo
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Re: Tiny Terror Hard Wired repair / resistor

Post by Structo »

That is strange that a modern amp, especially one of low wattage like that would be point to point.

Where are those made?
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selloutrr
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Re: Tiny Terror Hard Wired repair / resistor

Post by selloutrr »

Structo wrote:That is strange that a modern amp, especially one of low wattage like that would be point to point.

Where are those made?
They make two versions of the Tiny Terror one is PCB (UK / China) the other is Point to Point (UK/Spokane).
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mjbmjb
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Re: Tiny Terror Hard Wired repair / resistor

Post by mjbmjb »

Thanks for all the input. It seems like no one thinks there can be any degradation in performance so I should just relax.....

In the photo of the stock circuitry there seems to be no resistor
though...so it looks to me that this resistor is an addition, not a replacement. Could this be true?

I was just a little peeved that it came back, after a tube failure caused damage, with an addition to the circuitry and no explanation. It is now not stock anymore either, which could raise some eyebrows if I want to sell or trade.

I am not a builder or knowledgable about circuitry but I like to know what is going on....so thanks for the input.

Mike[/i]
Last edited by mjbmjb on Mon May 16, 2011 3:27 pm, edited 1 time in total.
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rp
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Re: Tiny Terror Hard Wired repair / resistor

Post by rp »

So the TT is also a boutique amp and I guess there is a $600 one and a $1200 one? Is it really that big a seller? I'm still amazed they went ptp.

Cliff, it's got to be the CR given the size and the cap across it but where is the CR in the 1st image? Maybe it was a little 3W ww and hidden below the cap?

To the OP - are the 2 images both of your amp, before and after? If so the amp's been practically rebuilt, look at the wire colors and parts placement, or they simply sent you a replacement, not that there's anything wrong w/ that, just noting.
mjbmjb
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Re: Tiny Terror Hard Wired repair / resistor

Post by mjbmjb »

I didn't have a photo of my amp before the repair, so the stock photo is off the net. The wires were different. The only thing is now there is this giant resistor....and I think you are right - this resistor is not a replacement, but an addition.
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rp
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Re: Tiny Terror Hard Wired repair / resistor

Post by rp »

mjbmjb wrote: this resistor is not a replacement, but an addition.
It could be part of the power string but most likely it's the CR. In either case it would be an up-rated part and not an addition/mod.

There is one odd thing in yours, there is a silver box on the input. Must be a cap cause they noticed RF noise at the input, a bit of a kluge IMO, but going by the name I guess this is a very high gain amp.
mjbmjb
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Re: Tiny Terror Hard Wired repair / resistor

Post by mjbmjb »

This is a real learning curve for me. CR = cap resistor? I'm not sure about the silver box.

In any case, it seems like everyone feels it is a good repair with no problems.

Again, I just had zero explanation about the new guts, and now have an amp that is not stock. So I just wanted to poke a few people in the know to just make sure a dummy, me, wasn't being taken advantage of with a cheap repair.

The Hard wired version of the TT is expensive, but I managed to get it for around 850 Canadian including tax...enough of an investment to be curious about the repair... :lol:
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