I have just had a Chameleon 1400S donated to me for spare parts. Having started dismantling it, I am intriuged by the bazarre
design (and what a *&^%$£ to work on!), there does not appear to be enough electronics in it for it to work! There are the balanced input and bridging electronics along the rear panel then another board which appears to be the cooling fan controler and peak LED driver gubbins. The output stage appears to be bipolar and to consist of 4 pairs of devices in each channel (have not dismantled this enough to read part numbers etc).....but where is the amplifier itself!?
The only thing I can think of is that it uses a topology similar to texas instruments "The Texan" from the early '70s in which an op-amp drives an output stage that has voltage gain, in which case the input board could be doubling up as the amp proper.
Whilst taking it to bits I found that one of the smoothing caps was leaking badly (burst can!), this was not visible until this stage of dismantling, and is probably the main/only fault in the beast (see where this is going
I am thinking of getting the thing up and runningcool: ) but I can find no info on this amp anywhere (other than spec....looks good). To cut to the chase, is there anyone on the site who has a circuit diagram and would be willing to share it? I see that Pinkmouse mentioned a possible schematic many moons ago but the thread seemed to die out. Any chance here Pinkmouse?
Thanks in advance,
Jez.
design (and what a *&^%$£ to work on!), there does not appear to be enough electronics in it for it to work! There are the balanced input and bridging electronics along the rear panel then another board which appears to be the cooling fan controler and peak LED driver gubbins. The output stage appears to be bipolar and to consist of 4 pairs of devices in each channel (have not dismantled this enough to read part numbers etc).....but where is the amplifier itself!?
The only thing I can think of is that it uses a topology similar to texas instruments "The Texan" from the early '70s in which an op-amp drives an output stage that has voltage gain, in which case the input board could be doubling up as the amp proper.
Whilst taking it to bits I found that one of the smoothing caps was leaking badly (burst can!), this was not visible until this stage of dismantling, and is probably the main/only fault in the beast (see where this is going
I am thinking of getting the thing up and running
cool: ) but I can find no info on this amp anywhere (other than spec....looks good). To cut to the chase, is there anyone on the site who has a circuit diagram and would be willing to share it? I see that Pinkmouse mentioned a possible schematic many moons ago but the thread seemed to die out. Any chance here Pinkmouse?Thanks in advance,
Jez.
Try this Chameleon 1400S stereo power amplifier. Free data sheet by GB Audio
I have a friend that uses this amp for testing loudspeakers great amp if you get it up and running
I have a friend that uses this amp for testing loudspeakers great amp if you get it up and running
Hi Sakis,
If you cast your mind back a couple of years you will recall that in the end I stripped the chassis and reverse engineered it. I obtained the schematic in this way and sent it to you before then putting it up on this site. We had extensive discussions by PM about it at the time......
The schematic I obtained by this method worked fine in simulation.
There is no point in me taking any photos of it now because it's just a box of bits in it's present form! There's some decent output devices from it that I will no doubt use at some point though.
Hi all!
I have a 2200s model which has the same schematics as 1400s just more output devices. Mine has a problem with fan control block. It has been repaired by someone before and does not work properly. The op-amp marked IC7 in the schematics from gb audio in my case does have no number/name on it. I suspect it was replaced and I wonder what was the original part. If some of you still has this device or has a part list can you please advise the part no. It is a 5-pin (at least in my case) op-amp above the fan terminal. Of course this part can be unavailable now but basing on the part no I would be able to determine it's parameters and choose a proper replacement.
Many thanks in advance,
Alexey.
I have a 2200s model which has the same schematics as 1400s just more output devices. Mine has a problem with fan control block. It has been repaired by someone before and does not work properly. The op-amp marked IC7 in the schematics from gb audio in my case does have no number/name on it. I suspect it was replaced and I wonder what was the original part. If some of you still has this device or has a part list can you please advise the part no. It is a 5-pin (at least in my case) op-amp above the fan terminal. Of course this part can be unavailable now but basing on the part no I would be able to determine it's parameters and choose a proper replacement.
Many thanks in advance,
Alexey.
Hi Alexey.
After 11 years, I guess there is no need for reply, but just for the history, the IC7 is a TDA2030.
Regards.
Hey guys
I just stumbled uppn this thread and am curious if still some ogf you care about this amölifier series and can give me some advice. I just bought this amplifier for very cheap and would like to have it running, but unfortunatelly the fan in mine always runs on max speed and therefore the unit is VEEERRRRYYY loud.
I sent the amp to an audio electronics expert and he just checked the amp and the schematics provided by GB audio also mentioned in this thread. So the repaisman told me that first the protection/fan comtrol circuit is not the same on the schmeatic than in my amp ans second the circuit is very complicated and doesn‘tcreally make sense to him. So here‘s my question:
1) does anyone have any help? Different schematics? Or tips about malfunctions with the fan?
2) If not: what dou you think: is it possible ro reduce the fan speed with a resistor so it runs low and quite? I will run this amp only in a studio where it is cold, there will be free space on top and bottom of the rack…
I am very thankful for every help!
Thanks,
Fabian
I just stumbled uppn this thread and am curious if still some ogf you care about this amölifier series and can give me some advice. I just bought this amplifier for very cheap and would like to have it running, but unfortunatelly the fan in mine always runs on max speed and therefore the unit is VEEERRRRYYY loud.
I sent the amp to an audio electronics expert and he just checked the amp and the schematics provided by GB audio also mentioned in this thread. So the repaisman told me that first the protection/fan comtrol circuit is not the same on the schmeatic than in my amp ans second the circuit is very complicated and doesn‘tcreally make sense to him. So here‘s my question:
1) does anyone have any help? Different schematics? Or tips about malfunctions with the fan?
2) If not: what dou you think: is it possible ro reduce the fan speed with a resistor so it runs low and quite? I will run this amp only in a studio where it is cold, there will be free space on top and bottom of the rack…
I am very thankful for every help!
Thanks,
Fabian