Downhome Upstate
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Got the itch to play with something for rock 'n roll. Anybody build the Triode ST70, the Dynakit Parts ST70 or the K&K rethink of that amp?
PP Amp kits qua Dyna ST-70?
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Downhome Upstate
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And I guess I should throw mods of stock ST-70's in the mix, like the one from Welborne Labs. I didn't think to include those because I haven't found a stock ST-70 for sale at a good price. Ebay prices for these amps seem consistently pretty high.
How much power do you need?
Downhome Upstate
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Caucasian Blackplate said:
Well, the room is 14w x 18l x 9h. The rig will be centered on the 14' wall. I don't have any speakers picked out yet. I was thinking about either factory refurb'ed Zu Omens - avg. 12 ohm, 97 db) at $999 a pair, or the Tekton Mini Lores (avg. 8 ohm, 95 db) at $650 a pair.
With a room that size and speakers that efficient, an ST-70 is not going to be all that useful.
Mike B said:
If we take the Tang W8-1772 as an example, specified excursion is 3mm. Assuming a perfect 8" cone diameter, this will allow low-ish distortion performance at:
89dB @ 40Hz
93dB @ 50Hz
96dB @ 60Hz
99dB @ 70Hz
105dB @ 100Hz
These numbers hold for a sealed box or IB alignment. A vented alignment can help the numbers around 50Hz, but not so much as you move up from there, and actually worse below.
This would suggest that ~8 Watts is a good power level for these drivers, though there's a big difference between linear Xmax and mechanical Xmax.
Yeah, with single drivers you can forget X max. Just adds to doppler distortion. Not good for rock & roll loud. Not good for anything loud.
For loud you need at least a 2 way.
In my bedroom, 12 x 12 x 8 feet, they sound good to ~80 dB average at 3 meters. I listen to ~67, got plenty of room. Classic rock every night. They give me tingles -
That badass system is in the garage. It has brought tears to my eyes. It hit's ~115 when the clip lights are blinking.
I don't do that much, not good for the ears. Just a song or 2. Once in a while. For old times sake. Damn it sounds good though -
For loud you need at least a 2 way.
In my bedroom, 12 x 12 x 8 feet, they sound good to ~80 dB average at 3 meters. I listen to ~67, got plenty of room. Classic rock every night. They give me tingles -
That badass system is in the garage. It has brought tears to my eyes. It hit's ~115 when the clip lights are blinking.
I don't do that much, not good for the ears. Just a song or 2. Once in a while. For old times sake. Damn it sounds good though -
Paul Joppa
Moderator
Football is a brutal game. Seattle, my home town, secured their position in the Super Bowl at home where we have the loudest fans in the league. I'm an acoustical engineer, so I may be the only person in Seattle who's not proud of that. I can guarantee that all 100,000 fans went home with some degree of permanent hearing damage.
Many serious rock fans are the same. And 35 watts is only 10dB more than 3.5 watts, not really enough to get to rock concert levels even in a modest size room unless you have fullrange horns at 112dB/w/m - which won't actually fit in a modest size room.
Nobody will care, but anything over 85dB-C sustained over a career will leave you just able to understand your corporate master's voice until the day you retire. At that point you become functionally useless to your corporate masters, so deafness is not an economic issue. Fortunately, even serious rock fans don't spend 8 hours a day for 40 years at rock concerts. Roadies and musicians however suffer the same fate as football players. It's a brutal game.
Many serious rock fans are the same. And 35 watts is only 10dB more than 3.5 watts, not really enough to get to rock concert levels even in a modest size room unless you have fullrange horns at 112dB/w/m - which won't actually fit in a modest size room.
Nobody will care, but anything over 85dB-C sustained over a career will leave you just able to understand your corporate master's voice until the day you retire. At that point you become functionally useless to your corporate masters, so deafness is not an economic issue. Fortunately, even serious rock fans don't spend 8 hours a day for 40 years at rock concerts. Roadies and musicians however suffer the same fate as football players. It's a brutal game.
Yeah Baby!
Yup, you know R&R.
I love my bedroom system. It's on every nite when I go to bed. I go to bed now at least an hour earlier than I used to just to listen to R&R. The Stereomour & the Tangbands give me much of the garage w/o the hearing damage. This system gave me insight to people who said they judged systems by how they sounded at low volume.
Yup, to get much of the same feel w/o the hearing damage is a good thing -
I don't think you can appreciate this fully w/o doing the 115 dB thing though. It gives you insight to why they call guitars "axes", at that level they cut right to your soul.
Yup, you know R&R.
I love my bedroom system. It's on every nite when I go to bed. I go to bed now at least an hour earlier than I used to just to listen to R&R. The Stereomour & the Tangbands give me much of the garage w/o the hearing damage. This system gave me insight to people who said they judged systems by how they sounded at low volume.
Yup, to get much of the same feel w/o the hearing damage is a good thing -
I don't think you can appreciate this fully w/o doing the 115 dB thing though. It gives you insight to why they call guitars "axes", at that level they cut right to your soul.
Ear plugs are pretty common in there these days, though at those levels, I'd want muffs and plugs.Paul Joppa said:
...JohnDownhome Upstate
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So, now that we've cleared that up, how about folks' experience with push-pull amp kits or projects based on used amps? Any takers? What did you build or tweak, how much did you spend, was the result satisfying? How tweakable was it?
Gerry E.
Member
Paul Joppa said:
Loud fans + Century Link Field acoustical design (use link below) = loudest outdoor sporting event!
http://www.businessinsider.com/seattle-seahawks-stadium-loud-2014-1
Gerry
I started my valve journey with a K12-G kit, 8 Watt, PP pentode. Sounded great. Then bought a Dared I30, 16 Watt, PP 6L6. Sounded better. Neither sounded as good as the class A elekit 6L6 and the flea power zero feedback Stereomour sounds the best.
Someday, when I've run out of other things to do, I'll get a big push pull valve amp to try in the garage. Or not as the case may be -
Someday, when I've run out of other things to do, I'll get a big push pull valve amp to try in the garage. Or not as the case may be -
Downhome Upstate
New member
Mike B said:I started my valve journey with a K12-G kit, 8 Watt, PP pentode. Sounded great. Then bought a Dared I30, 16 Watt, PP 6L6. Sounded better. Neither sounded as good as the class A elekit 6L6 and the flea power zero feedback Stereomour sounds the best.
Someday, when I've run out of other things to do, I'll get a big push pull valve amp to try in the garage. Or not as the case may be -
Mike,
Yup, love my Stereomour w/the Orcas & a sub for small-group jazz, acoustic anything, vocals, etc. I was thinking tubes for a rock and roll amp b/c I'm just starting to get comfortable w/understanding vacuum tube audio circuits. But if tubes and rock 'n roll music is where I want to go, maybe I should be thinking Mainline and some new phones.
Mike
Downhome Upstate
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corndog71 said:
How about some pics of that build as you go?
