ECP Torpedo III [indexed in first post]

Discussion in 'Headphone Amplifiers and Combo (DAC/Amp) Units' started by FlySweep, Nov 2, 2015.

  1. Alaarx

    Alaarx Facebook Friend

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    Is there a tube rolling guide for this amp somewhere? Impressions? Ive read the TomB ones but they're more technical / measurement based. Id love to find a set of tubes that give a bit of euphony / wetness to the amp.
     
  2. MisterRogers

    MisterRogers Friend

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    Generally, lean toward Mullard or Brimar NOS tubes. Certain Amperex tubes can bring some of that wetness, but lean toward the UK for your better choices with these attributes. Keep in mind, this amp is new, and the circuit is new. It's going to take some time / experimenting for the community to identify what works, sonic traits, etc.
     
  3. Alaarx

    Alaarx Facebook Friend

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    I read DrFindleys impressions of the Amperex 7062 and was thinking of trying those as they're not too expensive. Ill have a look at Mullard & Brimar thanks for the recommendations.
     
  4. drfindley

    drfindley Secretly lives in the Analog Room - Friend

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    There may be better tubes, but I sure liked these a lot. Definitely better than stock and more tube-y, but yet not overly tubey.
     
  5. MisterRogers

    MisterRogers Friend

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    Looking forward to it Doug. If you have a few moments, drop us a hint :) TIII has already won the 'most enjoyable build' status for the last year. We're pretty damn fortunate around here - being able to take part in this.
     
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  6. HitmanFluffy

    HitmanFluffy Hoping to see real genitals someday! - Friend

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    I'll second @MisterRogers opinion on British tubes being the most wet sounding tubes. I like my Mullard ECC81s for their warm, refined mids, but I missed the tight and focused bass of the stock tubes. I've recently rolled my RCA 12AV7 black plates and I really like the overall presentation after they were broken in. Before the break in they had this ridiculous "phat" bass that eventually calmed down to a mild mid-bass hump.
     
  7. dsavitsk

    dsavitsk Friend

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    The full details will have to wait, but basically this mod converts the output stage to be truly differential and by doing so isolates the signal current loop from the power supply.

    In other news, I have been trying different bypass caps - 0.1u in all cases. I tried AudioCap Thetas. They are definitely a big improvement over just the stock caps. To my ear, they're pretty natural and have a sound kind of like listening to records, or maybe a nylon string guitar - which might be called plastic-y. Reminds me a bit of the B&W sound from the late 80's to early 90's (before the Kevlar cones arrived). I also tried Cardas caps. Now I will say I have a thing against Cardas, and I won't buy or recommend anyone else buy, their products (I got them on sale and have had them in a box waiting for a project for years). That said, these do sound pretty good. They are 2x more expensive than the Thetas, but seem to eliminate any sort of sheen and are just very clean. I am not planning to do a huge cap trial, this was just a note about them making a bit of difference.
     
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  8. FlySweep

    FlySweep Friend

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    Very cool, Doug.. I really appreciate you continuing to tweak this amp to help us squeeze everything out of the design.
     
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  9. Alaarx

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    Im looking to buy the T3 in a few weeks and hopefully if the mod and cap trial are available i can built my own "uber" torpedo.
     
  10. drfindley

    drfindley Secretly lives in the Analog Room - Friend

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    Has anyone tried Duelund CAST-Cu Copper caps? (Would that even work?)
     
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  11. drfindley

    drfindley Secretly lives in the Analog Room - Friend

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    Wow, those are crazy expensive.
     
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  12. SoupRKnowva

    SoupRKnowva Official SBAF South Korean Ambassador - Friend

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    Was it not truly differential before?

    And fucking huge on top of being expensive haha
     
  13. Alaarx

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    Will I be able to order different cap options with the T3 kit or do I get them on top of the kit from somewhere like mouser? Sorry if this is a stupid question I've never built anything like this before.
     
  14. Alaarx

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    Another question (sorry again probably so basic) - Throughout the EC BW thread the big power supply got quite a few mentions as well as how much better the amp was when using the latest one and not the switching supply. 50% of the space in the new render is supposedly power supply. How does the T3 get away with sounding so fabulous while having a small PS (its a switcher isn't it)? Would it be another level of amazing if it had a big dedicated one or is it a case of individual implementation?
     
  15. dsavitsk

    dsavitsk Friend

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    Yes and no. It depends how close to infinity you need to get before you call it effectively infinite. The mod moves it a bunch closer.

    It will come with caps. If you want different ones (and we think the stock caps are pretty good) or bypasses you'll need to order them on your own. I would recommend building it stock first and thinking about mods later.

    PS is linear, not a switcher (there is nothing wrong with switchers, we just didn't use one here). It works well at its size for 3 main reasons - one is that this is a headphone amp, not a power amp, and it does not need a power supply of the size necessary to power speakers. The second is that there is a good quality regulator in it. The 3rd is that the circuit is differential which rejects power supply noise making it not that important.
     
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  16. badf00d

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    Even better? I can't wait.

    For the DIY-impaired, of these caps from the BOM, which did you replace? I'm going to buy the caps, but not sure which spec I need to target.

    • C1, C2 Electrolytic Snap-IN, 220uf 400V
    • C3 Electrolytic Snap-In, 3300uf 16V
    • C4 Electrolytic Radial, 100uf 25V
    • C5 Electrolytic Radial, 22uf 400V
    • C6 Film Cap, 10uf 300V
    • C7, C8, C9, C10[3] Film Cap, 10uf 300V
    Or do these go in some of the unused cap spots?
     
  17. TomB

    TomB MOT: Beezar

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    It's not replacing any caps. It's adding small bypass caps to the parafeed caps. So, you would add a second, very small (0.1uf) cap on top/in addition to/parallel to the parafeed caps - C7, C8, C9, and C10. There are plenty of holes in the PCB left over around the parafeed caps. I just received some Sonicap Gen II's at 0.1uf, 400V and the leads appear to be long enough to strap the caps to the top of the Epcos boxes and still reach one of the unused holes on both ends. (The Sonicaps are about the size of an inch-long #2 pencil.) I'm going to cover those bare leads with some teflon tubing that I have because that's too much bare metal at high voltage for my comfort. ;)

    I'll let you know if the Sonicap Gen II's sound OK. I hope so, because they're fairly inexpensive. I have yet to get the CCS's installed, however. I was fighting a hard drive failure in the last couple of days, so I haven't had much chance to do anything.
     
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  18. HitmanFluffy

    HitmanFluffy Hoping to see real genitals someday! - Friend

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    What is the VDC rating on those bypass caps you are using?
     
  19. dsavitsk

    dsavitsk Friend

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    300V DC is absolute minimum. I'd err on the side of a little higher. Mine are 600V.
     
  20. HitmanFluffy

    HitmanFluffy Hoping to see real genitals someday! - Friend

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    @dsavitsk Terrific, my source ran out of the lower voltages anyhow, so I can happily grab the 600Vs. I also dropped you an email about the CCS boards. Cheers!
     

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