Integrated amps with big transformers.

[southall-1998]

I strongly appreciate integrated amplification....employing big transformers. With plenty, copious amounts of current reverses.

What integrated amps, in the transformer region uses 500-1000va?

It could be dual mono as well!

I'm not on the market yet to buy. But give me a list :)

S.

[Frazeur1]

How about the U.S. built Coda CSiB integrated, I think it has a 2kva tranny, gobs of current delivery. Oh yeah, supposed to sound damn good too. I wouldn't mind listening to this on my Shahinian Obelisks!

[Colin Wonfor]

Hi Shane the TQ Claymore a a baby 500VA transformer.

[southall-1998]

Hi Shane the TQ Claymore a a baby 500VA transformer.

Really. I can't find that info on the web!

S.

[awkwardbydesign]

Jungson JA-88D(09). 700VA (or 800, depending on where you read it!) transformer. MC/MM phono stage, claimed 80W Class A (probably only 10W!), big meters.
http://www.jungson.com/products/hifi/ja88d I have the shiny SE version. And I have split the pre and power amps, with a switch so I can run it either way. Using an LDR pre at the moment, but it's not bad as a straight integrated amp.
http://www.fairaudio.de/img/test/jungson/jungson-88d-vorne-rechts.jpg

[Colin Wonfor]

No TQ do not any electronic now after I was pushed out.

[Ali Tait]

Jungson JA-88D(09). 700VA (or 800, depending on where you read it!) transformer. MC/MM phono stage, claimed 80W Class A (probably only 10W!), big meters.
http://www.jungson.com/products/hifi/ja88d I have the shiny SE version. And I have split the pre and power amps, with a switch so I can run it either way. Using an LDR pre at the moment, but it's not bad as a straight integrated amp.
http://www.fairaudio.de/img/test/jungson/jungson-88d-vorne-rechts.jpg

6-8W I believe.

[southall-1998]

What about those Karen amps?....can't recall the model number :scratch:

S.

[walpurgis]

http://www.whathifi.com/karan-acoustics/ka-i180-mk2/review

[southall-1998]

Thanks, Geoff.

S.

[walpurgis]

Hi Shane. If you want an outstandingly good and interesting integrated amp, check out Brinkman! ;)

[trio leo]

Hi Shane,
If you want amps with big transformers and large capacitors go to the Albarry website and check if their figures match your requirements, don't know anything about electrickery, but they look big to me.

Enjoy your music :)

cheers Al

[awkwardbydesign]

6-8W I believe.
http://www.troelsgravesen.dk/Duro.htm
I wonder about the class A power from the 30kg beast. Now that we have the schematics with component values, we can easily calculate how much power the amp really outputs in pure class A (and B if we want). Here are my findings.

PclassA = Irms x Irms x Rload.
There are two amps per channel in a bridged configuration, ie in total 4 amps - or amplifier stages if you like. Each of these stages has an idle current of (80mV to 100mV) / 0.25 Ohms x 2, as there are two pairs of output transistors per amp stage. Let´s use 100mV. Idle current aka
Ibias = 0.4x2=0.8A. This is the maximum current that a sine wave can have on the positive side. The negative side of course also can swing this much as we use a push pull design. So, Irms = 2 x Ibias / sqrt(2) = 1.13Arms.

Now we are ready to calculate the class A power that each of these four stages could deliver into a loudspeaker (Rload) :
P classA 8 Ohms = (1.13)^2 x 8 = 10.2 W
P classA 4 Ohms = (1.13)^2 x 4 = 5.1 W
P classA 2 Ohms = (1.13)^2 x 2 = 2.6 W
P classA 1 Ohms = (1.13)^2 x 1 = 1.3 W

Now, we do have two of these amps per channel in a bridged configuration. What does this mean for the class A power? Well, in bridged configuration, we have twice the voltage swing, so we get 4X the power, right? Yes, and no! We do get more class B power but do we really get more class A power? No, we do not.
Also note that in bridged mode, each amp “sees” half the Rload.

The power dissipation without music playing is high and that not only depends on the relatively high Irms but also because we have 4 amps.

[southall-1998]

Hi Shane,
If you want amps with big transformers and large capacitors go to the Albarry website and check if their figures match your requirements, don't know anything about electrickery, but they look big to me.

Enjoy your music :)

cheers Al

Nice one, Alan.

Thanks!

S.

[struth]

http://www.troelsgravesen.dk/Duro.htm
I wonder about the class A power from the 30kg beast. Now that we have the schematics with component values, we can easily calculate how much power the amp really outputs in pure class A (and B if we want). Here are my findings.

PclassA = Irms x Irms x Rload.
There are two amps per channel in a bridged configuration, ie in total 4 amps - or amplifier stages if you like. Each of these stages has an idle current of (80mV to 100mV) / 0.25 Ohms x 2, as there are two pairs of output transistors per amp stage. Let´s use 100mV. Idle current aka
Ibias = 0.4x2=0.8A. This is the maximum current that a sine wave can have on the positive side. The negative side of course also can swing this much as we use a push pull design. So, Irms = 2 x Ibias / sqrt(2) = 1.13Arms.

Now we are ready to calculate the class A power that each of these four stages could deliver into a loudspeaker (Rload) :
P classA 8 Ohms = (1.13)^2 x 8 = 10.2 W
P classA 4 Ohms = (1.13)^2 x 4 = 5.1 W
P classA 2 Ohms = (1.13)^2 x 2 = 2.6 W
P classA 1 Ohms = (1.13)^2 x 1 = 1.3 W

Now, we do have two of these amps per channel in a bridged configuration. What does this mean for the class A power? Well, in bridged configuration, we have twice the voltage swing, so we get 4X the power, right? Yes, and no! We do get more class B power but do we really get more class A power? No, we do not.
Also note that in bridged mode, each amp “sees” half the Rload.

The power dissipation without music playing is high and that not only depends on the relatively high Irms but also because we have 4 amps.

my mf a1000 had i think 8 transisters a channel producing 50w pure class a designed by Tim Paravicini

[southall-1998]

my mf a1000 had i think 8 transisters a channel producing 50w pure class a designed by Tim Paravicini


Can the A1000 still be serviced... by decent ''former'' Musical Fidelity Engineers?

S.

[Firebottle]

I can't see a problem getting it serviced if it's related to the A1 and A100, the circuit details are available on the web:

http://www.markhennessy.co.uk/mf_a1/technical.htm

:)

[DSJR]

The D'Agostino integrateds have big supplies I believe and there used to be a huge Levinson integrated too.

Shane, a giant transformer isn't a pre-requisite for a good sound in the same way you can't judge a man by the size of his todger (it's what he does with it and how he does it...). Same with amps. One of 'our' favourite amp ranges - cough - gets great sounds and fairly decent power levels (for domestic use) from quite modest supplies, although your Dad couldn't get enough for his Maggies? I remember - and these things need hundreds of Watts to make 'em work right I recall.

[technobear]

The ATC SIA2-150 :)

[southall-1998]

The ATC SIA2-150 :)

The MK1 version??

S.

[VesaLato]

ASR Emitter. Seriously expensive, too...

[technobear]

The MK1 version??

S.

I owned the Mk. 1 for a few years. Seriously good amp.

[Ali Tait]

http://www.troelsgravesen.dk/Duro.htm
I wonder about the class A power from the 30kg beast. Now that we have the schematics with component values, we can easily calculate how much power the amp really outputs in pure class A (and B if we want). Here are my findings.

PclassA = Irms x Irms x Rload.
There are two amps per channel in a bridged configuration, ie in total 4 amps - or amplifier stages if you like. Each of these stages has an idle current of (80mV to 100mV) / 0.25 Ohms x 2, as there are two pairs of output transistors per amp stage. Let´s use 100mV. Idle current aka
Ibias = 0.4x2=0.8A. This is the maximum current that a sine wave can have on the positive side. The negative side of course also can swing this much as we use a push pull design. So, Irms = 2 x Ibias / sqrt(2) = 1.13Arms.

Now we are ready to calculate the class A power that each of these four stages could deliver into a loudspeaker (Rload) :
P classA 8 Ohms = (1.13)^2 x 8 = 10.2 W
P classA 4 Ohms = (1.13)^2 x 4 = 5.1 W
P classA 2 Ohms = (1.13)^2 x 2 = 2.6 W
P classA 1 Ohms = (1.13)^2 x 1 = 1.3 W

Now, we do have two of these amps per channel in a bridged configuration. What does this mean for the class A power? Well, in bridged configuration, we have twice the voltage swing, so we get 4X the power, right? Yes, and no! We do get more class B power but do we really get more class A power? No, we do not.
Also note that in bridged mode, each amp “sees” half the Rload.

The power dissipation without music playing is high and that not only depends on the relatively high Irms but also because we have 4 amps.


Yes, that's the site I'd read. Interesting given the maker's claims..

[Yomanze]

ASR Emitter. Seriously expensive, too...

http://www.6moons.com/audioreviews/asr2/3.jpg

[awkwardbydesign]

Yes, that's the site I'd read. Interesting given the maker's claims..

They're Chinese; what did you expect? :lol: But 10w of Class A is not to be sneezed at, and apparently it gives more like 120w of Class B into 8 ohms. Still, I find it a very useful amp, especially as it can be modded. It won't be my permanent amp, but it's hard to see how I could afford to better it as a good substitute. And it has big blue meters! :smoking:

[Ali Tait]

Yes, as you say, 99% of what you are listening to will be in Class A. Same with my Kraken, it's only about 2-3w Class A. Plenty for what I'm using it for though, it only does 200Hz and up.

[Colin Wonfor]

I can't see a problem getting it serviced if it's related to the A1 and A100, the circuit details are available on the web:

http://www.markhennessy.co.uk/mf_a1/technical.htm

:)

I like this web site thanks for posting.

Col