all my home audio and musical gear was stolen out of a storage unit. in the market for new stuff. this time i wanna try a tube amp. my only concern is power. is it enough to power full range speakers with 88 db efficiency? everybody i know that uses tube amps listen to stuff like jazz and classical. i listen to 80% metal, 10% industrial, and 10% war theme classical. i like a forward in your face sound, good bass, and clean highs without making your ears bleed. for speakers, i've always wanted some klipsch rf-7's. i had the rf-83's and i couldn't stand them. loud as hell, but lacked solid bass. kick-drum wasn't too good with those speakers. better for ht, rather than 2ch. i also wanna build my own tube amp. not toally from scratch because i'm a noob. i wanna do a trial session to see if i even like tube sound. will this be a good diy kit? any suggestions on which direction i should go would be greatly appreciated. i dont wanna spend no more than $1000 on my first tube amp. thanx.
TriodeElectronics Dynaco ST-70 Tube Amp Kit
TriodeElectronics Dynaco ST-70 Tube Amp Kit
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Yes, the ST-70 is a good amp for the price. It's 35 WPC. The Mark III would better suit your power requirements (they are 60 Watts each), but a pair of those will set you back a little more than your budget.
It may be worth reconsidering your budget. Every 3 dB in sound level increase requires doubling your amp's power.
With speakers of 88 dB/Watt you will require almost 4 times the power that I do to drive my 93 dB/Watt speakers I built. Given 80% of your listening is hard rock, I would err on the side of more power rather than getting something underpowered and then selling it at a loss to buy something with more power.
However, if you are really thinking of rolling your own amp from scratch and want to get your feet wet first and can live with 35 WPC on a temporary basis (assuming 35 WPC is not enough), then the ST-70 is not a bad choice to learn from.
It may be worth reconsidering your budget. Every 3 dB in sound level increase requires doubling your amp's power.
With speakers of 88 dB/Watt you will require almost 4 times the power that I do to drive my 93 dB/Watt speakers I built. Given 80% of your listening is hard rock, I would err on the side of more power rather than getting something underpowered and then selling it at a loss to buy something with more power.
However, if you are really thinking of rolling your own amp from scratch and want to get your feet wet first and can live with 35 WPC on a temporary basis (assuming 35 WPC is not enough), then the ST-70 is not a bad choice to learn from.
sooo... your saying i would be better off buying two mark lll's, running them mono? i think the rf-7's are 92 db, but i hear they like power. if i run the mark lll mono, will that give me 120 watts x 1 @ 8ohm?
"i think the rf-7's are 92 db, but i hear they like power."
Huh? I don't know what that means, "like power". If a speaker puts out 92 dB/Watt at one meter and another puts out 88 dB/Watt at one meter, the second set of speakers will require just over twice the power in Watts to generate the same sound pressure level (SPL). Maybe "likes power" means that they won't self destruct if driven hard?
If you get two Mk IIIs, connect each one to each speaker (left and right) and play them in stereo. The MK III should have 4 and 8 Ω taps, so use whichever tap matches the speaker you connect it to. Two MK IIIs will give you almost twice the power than the ST-70. If you use KT-88 output tubes for the MK III you will get a little more balls to your bass than the ST-70 delivers. That is a little subjective, but most people agree.
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Go find some KLFs. I have the 10s (98dB), but the 20s are even better (100dB). I like rock, metal, and trance/techno as well. Wall shaking bass with just 8WPC. The ST70 shakes the house.
RF-7 is 102dB @ 2.83 volts/1 meter. You could probably get away with an ST-70 in triode mode.
Klipsch Classic RF-7 Floorstanding Speaker - Tower Speaker, Floor Speaker, Loudspeaker, Home Theater - Free Shipping - 30 Day Satisfaction Guarantee - Specifications
Klipsch Classic RF-7 Floorstanding Speaker - Tower Speaker, Floor Speaker, Loudspeaker, Home Theater - Free Shipping - 30 Day Satisfaction Guarantee - Specifications
klf 20's are hard to find, i also think the rf-7 would have a better compression driver. they look almost identical. teo 10" midrange drivers and a horn...
i never got a chance to listen to some rf-7's... like i said above, i didnt like the rf-83's. whats the bass responce on your rf-7's? sound good in 2ch. mode with no sub?
They come up on Craigslist from time to time. They weigh a ton, so eBay isn't realistic unless they are local. I got my KLF-10s for $150, which I only discovered later was a steal. They usually go for 300-500, depending on condition. Still, I would like to find a pair of 20s someday as the 10s are lacking in the midrange somewhat.
RF-7 looks like a fine modern substitute if you can afford them (I can't).
RF-7 looks like a fine modern substitute if you can afford them (I can't).
hmmm... they got a pair of klf 20's on ebay right now. no reserve, in mint condition. i almost wanna bite on these. op doesnt have any feedback though 🙁
They have a somewhat smooth sound with a very slight bias toward the midrange. Mine were running stock except updated power supply and coupling caps.
Speakers, and room interaction will determine what wattage and if you need solid state amps.
Asking "what kind of sound is to be expected from that amp?" makes sense, but it cannot be answered.
I have Paradigm Titan speakers in my kitchen. with an integrated 14 watt amp, and my MP3, I can drive myself out of the kitchen if I try and run the volume at 12 O'clock. When I take a shower, I'll turn the volume to 12 O'clock and leave the bathroom door open.
The Paradigm Titans are around 88-89db and 6-8 ohm speakers. I still listen to Hendrix.
Speakers first, with an eye for speakers that can be run with tubes, then look for the amp. I use a Scott 222A for the kitchen. I've had great FUN listening to a Heathkit integrated AA-151, also 14 watts. I bought some HeathKit WM3 monoblocks to rebuild, PP 6L6GC. More output than the PP EL84, but so far, my Scott sounds a lot better.
The output tubes I use in my Scott 222A cost more than the unit. the 12AX7s I use in my FM3 Dynaco tuner cost more than the tuner. The 12AX7s I use in the tone control in my Scott 222A cost almost as much as the unit. The rectifier tube in my SCott 222A costs about 1/3 of the unit.
Best from Tucson
Bob
Asking "what kind of sound is to be expected from that amp?" makes sense, but it cannot be answered.
I have Paradigm Titan speakers in my kitchen. with an integrated 14 watt amp, and my MP3, I can drive myself out of the kitchen if I try and run the volume at 12 O'clock. When I take a shower, I'll turn the volume to 12 O'clock and leave the bathroom door open.
The Paradigm Titans are around 88-89db and 6-8 ohm speakers. I still listen to Hendrix.
Speakers first, with an eye for speakers that can be run with tubes, then look for the amp. I use a Scott 222A for the kitchen. I've had great FUN listening to a Heathkit integrated AA-151, also 14 watts. I bought some HeathKit WM3 monoblocks to rebuild, PP 6L6GC. More output than the PP EL84, but so far, my Scott sounds a lot better.
The output tubes I use in my Scott 222A cost more than the unit. the 12AX7s I use in my FM3 Dynaco tuner cost more than the tuner. The 12AX7s I use in the tone control in my Scott 222A cost almost as much as the unit. The rectifier tube in my SCott 222A costs about 1/3 of the unit.
Best from Tucson
Bob
Bob is correct. It is not really possible to quantify the sound you will get because the room interaction plays such a huge part of the equation.
Dynaco was sort of the Volkswagen of stereo amps in its day. You can find forums for that gear. Dynaco equipment is good quality at a reasonable price. I think you can't go wrong. Are there better amps? Sure, but you won't find them in Dynaco's price range. There are worse amps, too.
As far as what any speaker sounds like as far as bass goes, that is way too subjective a question to get a meaningful answer to. Again, the room is so much more than 50% of the equation and can easily kill the bass of any speaker. I guess you can get some information about transient response, etc., but the best starting point is with the specifications and audio reviews under controlled conditions. At least that gives you a relative comparison guide to go by.
I should add, that tube sound is somewhat subjective compared to solid state. If you were to compare two high end amps (one tube and the other solid state) chances are you would not be able to tell the difference if both are operated below the point where audible distortion is present (< 1 to 2 %). I found a little better stage imaging with my amp over my Harman/Kardon AVR 525, but that is just my subjective opinion. I designed and built my own amp from scratch and probably could have bought a Quad 909 solid state amp for the amount of money I put into it and had a little better performance.
However, I liken tube amps and solid state amps to comparing a 1966 Jaguar XKE to a 2010 Porsche Boxster S. Both have similar performance with the edge going to the modern car and the Boxster will be cheaper to maintain and drive, but which car would you really rather drive? There really is no wrong answer, but I think the Jag has more class and that is why my amp glows a soft blue/orange.
Disclaimer: I do own a Porsche, but I also need it as a daily driver, too, and as much as I would love to own an XKE, it just would not be possible for me, so I am happy (and lucky) to drive what I drive. 🙂
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I wouldnt jump right in with a fully spent $!K budget if youve never run a tube amp before. Especially spending that much or more and going mono blocks either. If youre concerned about not having enough push or power for your 88db speakers, go with something reliable and less expensive like a Yaqin MC-100b first. It may be your last tube amp you will ever want (you might never want another because it will be enough kick and quality to last).
Good point, but he also wanted to build a kit amp (or am I wrong?) and the Yaqin MC-100b comes assembled from what I can determine. Dynaco clone kits are a low risk way to get started and still get quality sound.
I scratch built a higher end hotroded ST-70, and also listen to alot of classic rock, and older metal. With 86db speakers, the 70 is almost enough. Almost. I'd now say something with 2 KT88's per channel to be safe for using a variety of speakers. With more effecient speakers the 70 may do it. I'm skipping the tube rectifier this time around hoping for that little bit extra in the punch, and bass department.
That would be my concern. The music that the original post outlined can be pretty dynamic. 35 WPC channel can fill a room, but you can quickly run out of steam when something transient comes along (drums, whatever) and push the amp into the clipping zone. Bass is the hardest and 50% of music power is below 500 Hz. That was why I tend to error on the side of extra wattage, if the budget can be stretched a little.
If not, maybe searching for higher efficiency speakers is a good route and it gives you more flexibility in the choice of amps.
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