Hi all
I am a newbie looking to dip my toes in to tube audio. I want to dive a pair of bookshelf speakers in a medium sized room [say 14x14ft]. I don't play very loud in any case and mostly listen to old rock, some opera, instrumental etc. I have some experience in soldering and my fair share of healthy fear of high voltage. I think I will be ok making a kit or buying readymade.
Any suggestions for someone like me, to have a stereo amp, putting out around 7-10 WPC, for under $200? If I am being silly/unrealistic, please point out. I had been looking online and have a couple of things I have seen but not sure. I am hoping I am not starting some holy war. I am looking for some guidance from someone seasoned.
Thanks a bunch.
https://www.walmart.com/ip/6N1-6P3P...w7_Fo5k1m1VSpAXTjvU--cUTVgiHNMxQaAkNaEALw_wcB
Model K12G Stereo Tube Amplifier Kit
| TubeDepot.com
TubeCube | 7 Stereo Vacuum Tube Amplifier
| TubeDepot.com
Amazon.com: Stereo Integrated Tube Amplifier DIY Kit: Home Audio & Theater
I am a newbie looking to dip my toes in to tube audio. I want to dive a pair of bookshelf speakers in a medium sized room [say 14x14ft]. I don't play very loud in any case and mostly listen to old rock, some opera, instrumental etc. I have some experience in soldering and my fair share of healthy fear of high voltage. I think I will be ok making a kit or buying readymade.
Any suggestions for someone like me, to have a stereo amp, putting out around 7-10 WPC, for under $200? If I am being silly/unrealistic, please point out. I had been looking online and have a couple of things I have seen but not sure. I am hoping I am not starting some holy war. I am looking for some guidance from someone seasoned.
Thanks a bunch.
https://www.walmart.com/ip/6N1-6P3P...w7_Fo5k1m1VSpAXTjvU--cUTVgiHNMxQaAkNaEALw_wcB
Model K12G Stereo Tube Amplifier Kit
| TubeDepot.com
TubeCube | 7 Stereo Vacuum Tube Amplifier
| TubeDepot.com
Amazon.com: Stereo Integrated Tube Amplifier DIY Kit: Home Audio & Theater
My 2 cents.
Of the three Amp you listed, The S3 Model K12G will likely give you the least problem and sound the best at the get go. The other two can be made to sound good. However, you will need to know about Tube designs and will have to change the circuit a bit. The small one may be under power also. Do note that the Model K12G does not contain a Chassis and you have to make one yourself. And later on down the line, you want to change the Output transformer for better base performance. This one is most suitable for newbie, IMHO.
Of the three Amp you listed, The S3 Model K12G will likely give you the least problem and sound the best at the get go. The other two can be made to sound good. However, you will need to know about Tube designs and will have to change the circuit a bit. The small one may be under power also. Do note that the Model K12G does not contain a Chassis and you have to make one yourself. And later on down the line, you want to change the Output transformer for better base performance. This one is most suitable for newbie, IMHO.
Time out, please. Tube amps exhibit low damping factors, when compared to SS. That means speakers with comparatively flat impedance curves are in order. To avoid needless disappointment, tell the "crowd" what speakers are intended to be used, prior to spending hard earned cash.
JMO, better to "bust" the budget and a get satisfactory result than stay within the planned $ amount and up with a dung pile. The "big ticket" items in building a tube amp are magnetics (transformers and chokes). Edcor's CXPP25-8K transformer will support 6V6 "family" and EL84 O/P tubes and end up producing a useful amount of power. "Cloning" the Dyna ST35 using this boards/parts combo seems straight forward. This AnTek toroid easily takes care of energizing the "beast".
JMO, better to "bust" the budget and a get satisfactory result than stay within the planned $ amount and up with a dung pile. The "big ticket" items in building a tube amp are magnetics (transformers and chokes). Edcor's CXPP25-8K transformer will support 6V6 "family" and EL84 O/P tubes and end up producing a useful amount of power. "Cloning" the Dyna ST35 using this boards/parts combo seems straight forward. This AnTek toroid easily takes care of energizing the "beast".
The Edcor O/P transformers are $147.92/pair. The AnTek power transformer is $40. The parts/boards are $95. A decent quartet of EL84/6BQ5 O/P tubes is under $50. More like $400 complete, with you providing the case work.
A snowball in Hell has better odds than those Pioneer speakers working, sorry.
That 84 dB. sensitivity is a "lie", as 2.83 V. into 6 Ω is 1.3 W., not 1 W. In addition, you have to use the 4 Ω speaker taps and that makes the "true" sensitivity 81 dB. You don't listen very loud, but still upwards of 50 WPC are needed. Big $ with PP KT88s for those "puppies". TANSTAAFL!
Which Klipsch model do you own?
A snowball in Hell has better odds than those Pioneer speakers working, sorry.
That 84 dB. sensitivity is a "lie", as 2.83 V. into 6 Ω is 1.3 W., not 1 W. In addition, you have to use the 4 Ω speaker taps and that makes the "true" sensitivity 81 dB. You don't listen very loud, but still upwards of 50 WPC are needed. Big $ with PP KT88s for those "puppies". TANSTAAFL!Which Klipsch model do you own?
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A bit left field, but have you considered an old Magnavox console stereo amplifier? Just not sure how much they fetch in the States?
The 88-02 (6V6) and 93-02 (6BQ5 / EL84) chassis might fit the bill. 8 + 8 watts into 3 or 4 ohms. Certainly will need the coupling caps replacing and maybe the electrolytics too, but small change.
Plenty of information online and easy to work on and mod.
Alan
The 88-02 (6V6) and 93-02 (6BQ5 / EL84) chassis might fit the bill. 8 + 8 watts into 3 or 4 ohms. Certainly will need the coupling caps replacing and maybe the electrolytics too, but small change.
Plenty of information online and easy to work on and mod.
Alan
Attachments
The Edcor O/P transformers are $147.92/pair. The AnTek power transformer is $40. The parts/boards are $95. A decent quartet of EL84/6BQ5 O/P tubes is under $50. More like $400 complete, with you providing the case work.
A snowball in Hell has better odds than those Pioneer speakers working, sorry.
Which Klipsch model do you own?
I will go behind the media cabinet tonight and find the model of Klipsch.
Thanks
My 2 cents.
Not trying to sell the K12G. It is a good one to start with for learning tube and Tube sound. JMO, Build it. Play with it. When you are ready (learn how to do it). Buy a set of good output transformer and learn to change it to Ultra Linear or Triode mode. When you are done, put the old one back and pass it on to the next person. Note: If you do that make sure you buy transformer that could meet your end goal (ie: Design it for 8K primary and the chasis look good fitting both). When you are done with it, reuse the Transformer for a better circuit like the two discussed (ST35 and Baby Huey). But if you want a good one from the get go, yes Spending more at this price range is not a bad thing.
Not trying to sell the K12G. It is a good one to start with for learning tube and Tube sound. JMO, Build it. Play with it. When you are ready (learn how to do it). Buy a set of good output transformer and learn to change it to Ultra Linear or Triode mode. When you are done, put the old one back and pass it on to the next person. Note: If you do that make sure you buy transformer that could meet your end goal (ie: Design it for 8K primary and the chasis look good fitting both). When you are done with it, reuse the Transformer for a better circuit like the two discussed (ST35 and Baby Huey). But if you want a good one from the get go, yes Spending more at this price range is not a bad thing.
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Some isolation transformers are designed to go between the wall and the existing plug making them easy to use.
8+ WPC will be adequate with the Klipsch speakers.
Notice that the B3s are 3 dB. down at 55 Hz. We can bandwidth limit the circuitry to block the power "hungry" deep bass. In turn, less expensive O/P "iron" can be employed, to control costs. Repeat, magnetics are the big ticket in tube amp building. Edcor's GXPP15-8K in an ultra-linear (UL) mode "El Cheapo" will have power to spare. ANY 6V6 family tube will work in the design. A complete set of power magnetics can be sourced from Allied Electronics for less than $100. Suitable parts and tubes can be bought from Jim McShane. Change the 0.056 μF. value to 0.033 μF. That raises the LF limit to 48 Hz. Connect the O/P tube screen grid resistors to the UL taps, not the plates.
Notice that the B3s are 3 dB. down at 55 Hz. We can bandwidth limit the circuitry to block the power "hungry" deep bass. In turn, less expensive O/P "iron" can be employed, to control costs. Repeat, magnetics are the big ticket in tube amp building. Edcor's GXPP15-8K in an ultra-linear (UL) mode "El Cheapo" will have power to spare. ANY 6V6 family tube will work in the design. A complete set of power magnetics can be sourced from Allied Electronics for less than $100. Suitable parts and tubes can be bought from Jim McShane. Change the 0.056 μF. value to 0.033 μF. That raises the LF limit to 48 Hz. Connect the O/P tube screen grid resistors to the UL taps, not the plates.
Attachments
Found this one. Is something like this is what you have in mind?
1960’s Vintage Magnavox Stereo Tube Amp Model 9302-10, 4xEL84, 6BQ5 | eBay
The 9302-10 is a "Rolls Royce", among console amps.
The 5U4GB rectifier is 250 mA. capable and more than good enough for the signal tubes. The power transformer is substantial, as it and the rectifier powered both the amp and a separate tuner/preamp. The presence of a filter choke is a truly nice touch and rare among the genre.
The "weak link" lies in the O/P transformers and probably doesn't matter much with the bass extension limited Klipsch speakers. All electrolytic caps. must be replaced and the signal caps. are also replacement candidates. Carbon composition resistors should be checked for drift and noise.
Such an acquisition can be built on to drive better speakers, should the experience prove pleasurable. That would be an affordable way to "test the water".
The 5U4GB rectifier is 250 mA. capable and more than good enough for the signal tubes. The power transformer is substantial, as it and the rectifier powered both the amp and a separate tuner/preamp. The presence of a filter choke is a truly nice touch and rare among the genre.
The "weak link" lies in the O/P transformers and probably doesn't matter much with the bass extension limited Klipsch speakers. All electrolytic caps. must be replaced and the signal caps. are also replacement candidates. Carbon composition resistors should be checked for drift and noise.
Such an acquisition can be built on to drive better speakers, should the experience prove pleasurable. That would be an affordable way to "test the water".
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