Cambridge A75 Power Amp
 

One for the old timers on the list :-)

My Cambridge A75 power amp has a dodgy left hand channel.

I have two choices:

1. Get it repaired - I'd like to do this because, when it was working
I was very happy with it, however I've no idea where to take it :-( No
one at Cambridge Audio was old enough to even remember this amp so
I've got no circuit diagram....

2. Get a different, new-to-me, power amp to compliment my C75 pre-amp
(which I'd like to still use because a) I'm poor b) it has an MC input
for my deck/cartridge).

So, any advice? :-) Option 1. where do I take or send it to be worked
on or Option 2. recommended complimentary amp?

Cheers

Steve

Cambridge A75 Power Amp
 

On 10 Apr 2007 05:28:32 -0700, "solwisesteve"
wrote:

One for the old timers on the list :-)

My Cambridge A75 power amp has a dodgy left hand channel.

I have two choices:

1. Get it repaired - I'd like to do this because, when it was working
I was very happy with it, however I've no idea where to take it :-( No
one at Cambridge Audio was old enough to even remember this amp so
I've got no circuit diagram....

2. Get a different, new-to-me, power amp to compliment my C75 pre-amp
(which I'd like to still use because a) I'm poor b) it has an MC input
for my deck/cartridge).

So, any advice? :-) Option 1. where do I take or send it to be worked
on or Option 2. recommended complimentary amp?

Cheers

Steve

I think the poverty thing clinches it. Repairing it will be expensive.
Have a look on Ebay for a Cyrus II amp - there are always plenty
around. They have a superb phono stage which is switchable between MM
and MC. Certainly better than the C75, and also very compact and
convenient.

d

--
Pearce Consulting
http://www.pearce.uk.com

Cambridge A75 Power Amp
 

I think the poverty thing clinches it. Repairing it will be expensive.
Have a look on Ebay for a Cyrus II amp - there are always plenty
around. They have a superb phono stage which is switchable between MM
and MC. Certainly better than the C75, and also very compact and
convenient.

Thanks for the reply...
TBH I was kind of thinking the repair cost was going to be too high.

The Cyrus is a quite bit lower power than the outgoing A75..... I'm
pairing this up with Ruark Swordsman Plus speakers... do you think the
Cyrus will have enough oomph? :-)

Cambridge A75 Power Amp
 

On 10 Apr 2007 05:54:08 -0700, "solwisesteve"
wrote:

I think the poverty thing clinches it. Repairing it will be expensive.
Have a look on Ebay for a Cyrus II amp - there are always plenty
around. They have a superb phono stage which is switchable between MM
and MC. Certainly better than the C75, and also very compact and
convenient.

Thanks for the reply...
TBH I was kind of thinking the repair cost was going to be too high.

The Cyrus is a quite bit lower power than the outgoing A75..... I'm
pairing this up with Ruark Swordsman Plus speakers... do you think the
Cyrus will have enough oomph? :-)


Plenty.

d

--
Pearce Consulting
http://www.pearce.uk.com

Cambridge A75 Power Amp
 

The Cyrus is a quite bit lower power than the outgoing A75..... I'm
pairing this up with Ruark Swordsman Plus speakers... do you think the
Cyrus will have enough oomph? :-)

Plenty.

Thanks :-)

Cambridge A75 Power Amp
 

solwisesteve wrote:
One for the old timers on the list :-)

My Cambridge A75 power amp has a dodgy left hand channel.


I had one years ago - marvellous amp.

I have two choices:

1. Get it repaired - I'd like to do this because, when it was working
I was very happy with it, however I've no idea where to take it :-( No
one at Cambridge Audio was old enough to even remember this amp so
I've got no circuit diagram....


The C75 packed in on me. I took it to a TV repair shop, where the deal
was 25UKP 'inspection fee', which would be taken off the bill if I went
ahead with the repair. He fixed it for 30UKP*. But it might be worth
asking at a repair shop?


2. Get a different, new-to-me, power amp to compliment my C75 pre-amp
(which I'd like to still use because a) I'm poor b) it has an MC input
for my deck/cartridge).


I thought the C75 was very good - especially the MC input. I'll defer to
Don, having never heard the Mission's MC input, or indeed either amp at
all for many years.

Rob

* Eventually I destroyed the power amp driving some Dynaudio speakers.
At that point I cut losses and flogged the pair as broken - got about
60UKP (plus postage at 70UKP to Norway). I think the bloke wanted them
for the cases, switches and transformers. And why not.

Cambridge A75 Power Amp
 

"solwisesteve" wrote in message
ups.com...
One for the old timers on the list :-)

My Cambridge A75 power amp has a dodgy left hand channel.

I have two choices:

1. Get it repaired - I'd like to do this because, when it was
working
I was very happy with it, however I've no idea where to take it
:-( No
one at Cambridge Audio was old enough to even remember this amp so
I've got no circuit diagram....

2. Get a different, new-to-me, power amp to compliment my C75
pre-amp
(which I'd like to still use because a) I'm poor b) it has an MC
input
for my deck/cartridge).

So, any advice? :-) Option 1. where do I take or send it to be
worked
on or Option 2. recommended complimentary amp?

Cheers

Steve


Define 'dodgy left channel'?

It may not be a fault as such, or it maybe something that someone with
a soldering iron can fix in minutes.

Other than that, Richer Sounds have a very good repair department, and
they'll lend you an amp whilst it is away.


--
Woody

harrogate3 at ntlworld dot com

Cambridge A75 Power Amp
 

On Apr 10, 8:08 pm, "harrogate3" wrote:
Define 'dodgy left channel'?

Well it started to get a bit wooley on the left channel. I bit muffled
and quiet. This was most pronounced when switched on and, for a while
(read a few months) it would clear up after it was warmed up. However
it got gradually worse and then went completely. Then I moved house
and it stayed (along with the rest of my HiFi) boxed in the loft. That
was 5 years ago! Anyway we're just about to move to a new house which
has an extra room which is going to be my HiFi room so it's time to
get it out!


It may not be a fault as such, or it maybe something that someone with
a soldering iron can fix in minutes.

It's getting the time to look at it which I just don't have. I suppose
I could just resolder every joint :-) There can't be more than 20 per
channel.

TBH it all looks pretty standard parts except for one module which
looks like a custom job.

Hmmm.... just taken the lid off to remind myself..... Getting the PCB
out looks like a ba**ard - great big row of D896 power transistors
fixed to a large heat sink which is then attached to the rear of the
case :-(


Other than that, Richer Sounds have a very good repair department, and
they'll lend you an amp whilst it is away.

Richer Sounds.... now there's one in town - might give them a bell.

Cambridge A75 Power Amp
 

On Apr 11, 1:44 pm, "solwisesteve" wrote:

Hmmm.... just taken the lid off to remind myself..... Getting the PCB
out looks like a ba**ard - great big row of D896 power transistors
fixed to a large heat sink which is then attached to the rear of the
case :-(

Okay! I think I've fixed it :-)

Got the PCB out and then re soldered every joint.

Surprised to see that Cambridge Audio hadn't cleaned the flux off the
board - were they worried about cleaner getting into the caps? Strange
'cause when I used to design and build super high precision signal
input boards we used to make damn sure the boards were cleaned
afterwards to stop crosstalk between the tracks through the flux...
anyway I've left it in the uncleaned state.

So I've just had it running for an hour at 80% volume and the 'scope
shows a perfectly clean output on both channels! :-)

I tell you what though, the resisters load I was using got f**king
hot! :-)

Just need to do a proper live test now...

Thanks for all the advice.

Cambridge A75 Power Amp
 

I tell you what though, the resisters load I was using got f**king
hot! :-)

You remind me of one of my favourite quotes. Some HiFi magazine was
reviewing an amplifier with staggering (at the time) output power of
several hundred watts per channel which claimed to have complete output
protection, even against shorting. So they decided to test it by taking
the leads out of the speaker while running at full volume and brushing
them together.
"The result was large frightening sparks" has stuck in my memory ever since.
I'm glad your amp is back in business.

--
Steve Swift
http://www.swiftys.org.uk/swifty.html
http://www.ringers.org.uk