That is a BIG heatsink I wonder if they ever get hot.
Congratulations on the finished amplifier...so... any lisening tests?
(I am really curious comparing it with tube class-A amplifiers)
Congratulations on the finished amplifier...so... any lisening tests?
(I am really curious comparing it with tube class-A amplifiers)
Thanks Neazoi !
It is definately not hot after about a half hour running
I am listening now and i am happy so far - but i have to sleep will let you know more tommorrow
-Dan
It is definately not hot after about a half hour running
I am listening now and i am happy so far - but i have to sleep will let you know more tommorrow
-Dan
monster
hi dan,
very nice piece of work/building,
plenty place inside (for music dancing),
good central centerpoint "0Volt",
plenty heatsink,
quid: what's on (function) the pcb (outgoing) to the driver terminal?
and last: what are your's musical impressions (on what kind of drivers)?
best regards,
karel
hi dan,
very nice piece of work/building,
plenty place inside (for music dancing),
good central centerpoint "0Volt",
plenty heatsink,
quid: what's on (function) the pcb (outgoing) to the driver terminal?
and last: what are your's musical impressions (on what kind of drivers)?
best regards,
karel
Hi Karel,
The Function of that circuit is speaker dc protection/de thump
So far i have only listened for a little while but it sounds very good 🙂
I am using Elsinore Mk. 3 speakers.
-Dan
The Function of that circuit is speaker dc protection/de thump
So far i have only listened for a little while but it sounds very good 🙂
I am using Elsinore Mk. 3 speakers.
-Dan
Dan,
A nice job indeed... Congratulations.
Mine usually look like they were put together from stuff pulled out of the garbage, because... well.... 😱
OT: What circuit are you using for speaker protection?
Cheers
Nigel
A nice job indeed... Congratulations.
Mine usually look like they were put together from stuff pulled out of the garbage, because... well.... 😱OT: What circuit are you using for speaker protection?
Cheers
Nigel
Hi Nigel,
Thanks 🙂
The circuit i am using is a old silicon chip (aus magazine) one
It is a filter circuit which passes ac but activates a relay with dc, some square wave signals also can trip it similar to clipping...
I am sure they were not the first to use it. and there is many variants of it around. The kit is now discontinued and they have replaced it with a similar version but with thermal protection and some other stuff, i have one at home but i opted for this one it seemed a shame to waste it.
PS: your stuff does not look like rubbish more like a good use of surplus electronics !
-Dan
Thanks 🙂
The circuit i am using is a old silicon chip (aus magazine) one
It is a filter circuit which passes ac but activates a relay with dc, some square wave signals also can trip it similar to clipping...
I am sure they were not the first to use it. and there is many variants of it around. The kit is now discontinued and they have replaced it with a similar version but with thermal protection and some other stuff, i have one at home but i opted for this one it seemed a shame to waste it.
PS: your stuff does not look like rubbish more like a good use of surplus electronics !
-Dan
Thanks, but you should tell my wife that... ("You want to put WHAT in the living room???") 😉
I'll see if I can find anything about silicon chip online - thx for the ref.
Cheers
Nigel
Dan,
How would you compare it with your 20W monstre, or with your older monstre? Any audible differences?
How would you compare it with your 20W monstre, or with your older monstre? Any audible differences?
Hi all,
Neazoi, I think there is an audible difference to the Le class A 20W
the mostre seems a little bit more natural/better also requires a little bit more gain on the input..
it is able to go very loud with my Elsinore speakers so i am very happy at the moment it is what i listen to on a day to day basis
Actually i am very happy with the results - the heatsink runs at not much over room temp, and the amp is very quiet you have to have your ear right up near the tweeter to hear any noise with it connected but not signal - and this is mostly the cd player/preamp noise
I have not taken a very good pic of the amp from the outside but here is a pic anyway ... notice when i was at work one of the 2 cats has investigated the amp.... the top needs a wipe dusty for waiting to go onto the amp
and there is a small slit you can see through which i have to re-align...
-Dan
-Dan
Neazoi, I think there is an audible difference to the Le class A 20W
the mostre seems a little bit more natural/better also requires a little bit more gain on the input..
it is able to go very loud with my Elsinore speakers so i am very happy at the moment it is what i listen to on a day to day basis
Actually i am very happy with the results - the heatsink runs at not much over room temp, and the amp is very quiet you have to have your ear right up near the tweeter to hear any noise with it connected but not signal - and this is mostly the cd player/preamp noise
I have not taken a very good pic of the amp from the outside but here is a pic anyway ... notice when i was at work one of the 2 cats has investigated the amp.... the top needs a wipe dusty for waiting to go onto the amp
and there is a small slit you can see through which i have to re-align...
An externally hosted image should be here but it was not working when we last tested it.
-Dan
-Dan
Thank you Dan,
Are you able to make any comparisons with a vacuum tube class-A amplifier?
Now that is a little messy cat (they are always like this, so we like them 🙂 )
Are you able to make any comparisons with a vacuum tube class-A amplifier?
Now that is a little messy cat (they are always like this, so we like them 🙂 )
It seems this topic is inactive for quite a long, I guess all of you are in building stages 😀
I am on building stage too, everything ready, just a few connections left for the PSU capacitors, I will post pictures soon.
I have used battery only operation and non-magnetic BNC for the I/O ports in a configuration that I have post here K.Giannopoulos official site
I am on building stage too, everything ready, just a few connections left for the PSU capacitors, I will post pictures soon.
I have used battery only operation and non-magnetic BNC for the I/O ports in a configuration that I have post here K.Giannopoulos official site
I just tested the amplifier. all the I/O cables are messy but I couldn't wait to give it a go. It works, it amplifies, this means no error on the circuit, but the 1 Ohm resistors get too hot. Mine are 3.5-4W and the schematic suggests 5W.
With the configuration shown on http://www.audio-constructions.com/monstre/Hiraga-Monstre-Monster-Class-A-amplifier-schematic.png the voltage drop across the resistors is 2.7V!! I have not made any adjustments yet, I just wanted to see that it works for now. maybe that is why the resistors get too hot?
Oh something else I plugged the batteries using cables and no switch and I got a nice spark from the huge initial draw current of the caps.... You wonder if this sparc would exist inside the future added switch? No, if you add a switch there is no spark I have tested it.
Not even adjusted and the sound is very transparent and it seems the bass region goes too low. The middle and highs are just excellent I have not heard anything like this before. I wonder how they will be when adjusted.
The volume is exceptionally high I guess it is much more sensitive than I thought, perfect for a passive preamplifier, as I had to adjust the volume of the internal attenuator of the CD to the minimum and still it was very loud for my room (I have 90-102dB speakers).
An exciting moment to see everything working as expected!
I cannot wait to make the adjustments (and replace the 1 ohm resistors with bigger wattage ones?)
With the configuration shown on http://www.audio-constructions.com/monstre/Hiraga-Monstre-Monster-Class-A-amplifier-schematic.png the voltage drop across the resistors is 2.7V!! I have not made any adjustments yet, I just wanted to see that it works for now. maybe that is why the resistors get too hot?
Oh something else I plugged the batteries using cables and no switch and I got a nice spark from the huge initial draw current of the caps.... You wonder if this sparc would exist inside the future added switch? No, if you add a switch there is no spark I have tested it.
Not even adjusted and the sound is very transparent and it seems the bass region goes too low. The middle and highs are just excellent I have not heard anything like this before. I wonder how they will be when adjusted.
The volume is exceptionally high I guess it is much more sensitive than I thought, perfect for a passive preamplifier, as I had to adjust the volume of the internal attenuator of the CD to the minimum and still it was very loud for my room (I have 90-102dB speakers).
An exciting moment to see everything working as expected!
I cannot wait to make the adjustments (and replace the 1 ohm resistors with bigger wattage ones?)
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I am just building the sides of the box of the amplifier currently, where all the I/O will be attatched.
I added a 2K good quality multi-turn potentiometer parallel to each of the 1K resistor to set the bias for class-A and hopefully to reduce the heat on the load resistors.
I will let you know very soon of the results.
PS. I am running it only from batteries.