You are being deceived
2x12 W with a consumption of 27 W pure class A?
Not less than 100 W (transformer 200 W)
Output on transistors TIP41. The radiator is small. This is 2x5 watts.
Capacitors 25 V 30,000 microfarads (30x1000). Supply voltage no more than 24V. Nothing is said about the load resistance. You may have to configure it yourself.
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Thanks for the feedback
Not worried about the output provided it's less than 20 watts per channel - any more than that will blow up the drivers in the speakers i'm going to build. Decaware Tiny Radials use some wicked little Tangband 4 Ohm drivers with built in passive radiators so should be OK for intended use. It's for desktop use I'll let you know how i get on- best part is that a lack of surface mount components should make it easy to tweak at a later date.
View attachment 264-938--tang-band-t2-2136sa-spec-sheet.pdf
Not worried about the output provided it's less than 20 watts per channel - any more than that will blow up the drivers in the speakers i'm going to build. Decaware Tiny Radials use some wicked little Tangband 4 Ohm drivers with built in passive radiators so should be OK for intended use. It's for desktop use I'll let you know how i get on- best part is that a lack of surface mount components should make it easy to tweak at a later date.
View attachment 264-938--tang-band-t2-2136sa-spec-sheet.pdf
There are several other standard 10W models available from China that are also complete, working and fitted in a single box for less money than that. None that I'm aware of have a preamp included but unless you are a vinyl addict, the JLH'69 and updated versions don't really need one.
Why not DIY build the amplifier though, starting with a super cheap PCB and parts that will be fine for the purpose of getting you going and enthusiastic about the electronics too?
Why not DIY build the amplifier though, starting with a super cheap PCB and parts that will be fine for the purpose of getting you going and enthusiastic about the electronics too?
Hi Ian
Thanks
I've already built two ACA and the Korg Nutube all with dedicated power supplies. I have the boards and main case for a Pearl two phono preamp as well that I need to finish. On this occasion I wanted something ready made and cheaper than the ACA that will fit in a specific spot on my desk. I may well pass it on to my sister so keeping it compact and visually appealing comes into the equation for that too.
Will try it out on the horns for a laugh -106db per Watt and powered subwoofers in each to boot In common with Decaware ones - no crossover the subwoofer is just adjusted to cut off at the overlap.
Thanks
I've already built two ACA and the Korg Nutube all with dedicated power supplies. I have the boards and main case for a Pearl two phono preamp as well that I need to finish. On this occasion I wanted something ready made and cheaper than the ACA that will fit in a specific spot on my desk. I may well pass it on to my sister so keeping it compact and visually appealing comes into the equation for that too.
Will try it out on the horns for a laugh -106db per Watt and powered subwoofers in each to boot
In common with Decaware ones - no crossover the subwoofer is just adjusted to cut off at the overlap.
There are a couple of small footprint, cheaper prebuilt models but I suspect they all run quite hot to the touch. I would be wary of passing any class A amplifier on to a family member or friend since being in contact with heatsinks or the case surrounding internal heatsinks, can be painful, even if not hot enough to burn you. Not everyone welcomes a surprise like that when fumbling about with their audio system, connectors and leads at the rear etc. I still get caught out, even after many years of messing with class A.
e.g. 1969 classic Circuit design class A HIFI power amplifier with full aluminum chassis|hifi power amplifier|a class amplifieramplifier a class - AliExpress
e.g. 1969 classic Circuit design class A HIFI power amplifier with full aluminum chassis|hifi power amplifier|a class amplifieramplifier a class - AliExpress
Thanks for the feedback
Not worried about the output provided it's less than 20 watts per channel - any more than that will blow up the drivers in the speakers i'm going to build. Decaware Tiny Radials use some wicked little Tangband 4 Ohm drivers with built in passive radiators so should be OK for intended use. It's for desktop use I'll let you know how i get on- best part is that a lack of surface mount components should make it easy to tweak at a later date.
View attachment 876937
SENSITIVITY 1W/1m 80 dB
POWER RECOMMENDED 20W (RMS)
Decaware have been running the Tangbands on 3 watt Zen Triode amps in all the videos they've posted - I can only assume poor data sheet wording and it means the max recommended is 20 watt which makes more sense for such a tiny driver. Put in perspective the speakers are only 6 1/2 inches tall.
I run some miniature Teac speakers of only 87 dB sensetivity on two times 1.7 watts. Whilst it isn't loud the bass can be a lot better than the TV. The main thing seems to be not to allow much to happen below 15 Hz. I have no Idea what those signals are. They don't make for more bass. I only use a first order filter. I built this for curiosity. I like it so use it daily. The Teac speakers were sold by different brands. Radio Shack and JVC. Very European in style. They resemble BBC LS35A, even the bass. In some ways I prefer the Teac. Fostex have interesting drivers if the typical full range dispersion çan be ignored. Not bad on axis. My previous speakers ran at 115 dB and were easy to use like that. Addictive and dangerous. Beatles music was spectacular.
For this thread your questions are fairly on target. Let us know if you get any hum with the power supply shown. To my way of thinking you might. Into four ohms I suspect that the power might be less than stated. As the speakers are efficient it probably will be OK. It's a nicely made unit which should be a pleasure to own.
87 dB. Sound is some kind of logarithmic scale. 1.7 watts needs 17 watts to be truely louder. Since I put a 15 Hz filter 1.7 watts can be louder than seems possible. The first watt principle is very true. If the sound is very detailed it seems louder. 5 watts should be very OK. The Dinsdale amp shown could be set for 1 to 3 watts A and 30 watts AB. That could be ideal. The time I missed power was steam locomotives! The old Decca test record. It was a 10 watt 300B amp. The echo in the station wasn't there. The old Hitachi MOS FET could do it. Nicest amp I have known and easy to make. Not unlike the AB JLH circa 1980. JLH said similar things.
Depends on what you mean "truly louder." It would be a lot louder, like subjectively about twice as loud.
Sound perception is logarithmic. Double the power and you increase spl by 3 dB. 3 dB is noticeably louder. 1 dB is the smallest change in spl that the human ear can perceive, on average.
Decibels can be confusing when we think linear. They help us convert our hearing (not linear) to something engineers can use to set design parameters and evaluate performance.
So there's two handy rules of thumb-
1) 10x power = about twice as loud
2) 2x power = 3 dB increase in spl
In 1975 I did these calculations.. As time passed I realized it wasn't a true science as some of it is personal and subjective. It's like how sweet a substance is. I found it highly unlikely we hear to base 10. None the less it's more correct than most guesses. I am willing to think 17 watts is usefully louder than 1.7 watts. 3 watts isn't.
Listening to my TV 1.7 watts, the bass can be percussive. TV has this as part of the experience. None the less it works against my training to think this is possible. I was listening to TV series Vera, the bass is unexpected. She is a quirky detective. It was a recording.
Listening to my TV 1.7 watts, the bass can be percussive. TV has this as part of the experience. None the less it works against my training to think this is possible. I was listening to TV series Vera, the bass is unexpected. She is a quirky detective. It was a recording.
Let me give another observation. The UK Klipsche distributor showed me many measurements he had made. He worked out that almost without exception most people use a maximum of 5 watts, Without any plan they choose larger speakers space willing. He often noticed compression of the sound above this level is due to the behaviour of the air. He thought car air seals a factor. He never published this work. Big amplifiers often sound nice because the PSUs are better. Yamaha had a class AB or A amplifier which exploited that.
Why believe what some guy says about what some other guy said?
I'm sure you could slap together a little circuit that performs peak detection + slow decay, connect its input to the two terminals of your loudspeaker, and then simply measure the peak voltage delivered to your speaker. Power = voltage * voltage / resistance. Easy!
For extra points, feed the peak voltage to an arduino single board computer and have it broadcast the readings over your wifi network. Download a VU-meter app for your phone and presto! You've got a peak detecting VU meter on your phone that you can show to gobsmacked visitors. Yer a wizard, Harry!
I'm sure you could slap together a little circuit that performs peak detection + slow decay, connect its input to the two terminals of your loudspeaker, and then simply measure the peak voltage delivered to your speaker. Power = voltage * voltage / resistance. Easy!
For extra points, feed the peak voltage to an arduino single board computer and have it broadcast the readings over your wifi network. Download a VU-meter app for your phone and presto! You've got a peak detecting VU meter on your phone that you can show to gobsmacked visitors. Yer a wizard, Harry!
Klipsch speakers are efficient. 5 watts of clean power will drive Klipshorns or Heresys to a satisfying level.
In high school I had big efficient speakers, 15" 3 way 97 dB/watt. They were driven by a 40 watts RMS a channel tube amplifier. It was the loudest stereo ever. They could play louder than you could endure without huffing and puffing. I set them up outside once for a block party and you could hear them a mile and a half away.