so the AD is just a replacement for the OPA?? Is it possible to connect your own amp. in there or is it part of the feedback loop?
Is there a schematic diagramm somewhere so I could see how the input is done? The OPA627 is a nice replacement for the 134 =about the same spec as the AD. Is easier to get in Europe at Farnell. The AD8620 is easier to get in the US. The price of the 627 and 8620 is nearly identical € 20,- while the 134 is only € 2,50
Is there a schematic diagramm somewhere so I could see how the input is done? The OPA627 is a nice replacement for the 134 =about the same spec as the AD. Is easier to get in Europe at Farnell. The AD8620 is easier to get in the US. The price of the 627 and 8620 is nearly identical € 20,- while the 134 is only € 2,50
The shipping OPA2134 is a nice opamp. Very common on pro audio equipments.
I'm sure that 20€ per module will be better used to buy the best capacitors.
I'm sure that 20€ per module will be better used to buy the best capacitors.
Hi,
I would never consider using the The OPA627 as a drop in replacement for either op amps concerned, it is hugely tempermental and requires extra effort to make it sound good as well, if they're close to the same cost you're far better off with the AD. In fact I'm not even sure it would be possible to make the OPA627 work at all in this.
I'm not sure they'd have the same sonic signiature either, look at the THD Vs frequency graph of the 8620, notice anything in particular? _______________________ That's why it is better.
You may also have to change a thing or two in order to upgrade to the 8620, used to be the zeners for their supplies, not sure if that's all been changed now or not.
Regards
I would never consider using the The OPA627 as a drop in replacement for either op amps concerned, it is hugely tempermental and requires extra effort to make it sound good as well, if they're close to the same cost you're far better off with the AD. In fact I'm not even sure it would be possible to make the OPA627 work at all in this.
I'm not sure they'd have the same sonic signiature either, look at the THD Vs frequency graph of the 8620, notice anything in particular? _______________________ That's why it is better.
You may also have to change a thing or two in order to upgrade to the 8620, used to be the zeners for their supplies, not sure if that's all been changed now or not.
Regards
The AD8620 is also the first thing that is used to mod CD/DVD players.
It's like a well known secret that these small components make or break a good quality system.
Even 1000$ DVD players seem to cut costs by using inferior opamps.
It's like a well known secret that these small components make or break a good quality system.
Even 1000$ DVD players seem to cut costs by using inferior opamps.
Ordered my UcD 400 at Speaker & Co in Groningen (Netherlands) Yesterday. Very anxious to find out how they sound compared to my Aleph 5's.
(Thanks Martin!)
Jan
(Thanks Martin!)
Jan
just saw the 8620 is a dual opamp so you cannot compare it to the OPA627. Should be the 8610. I use the OPA's in my DAC2000 and they sound pretty nice. They are not difficult to use at all. Just as a normal opamp.
But I agree that the AD86x0series is a better choice nowadays.
Pitty they don't have them as DIL8's. So I could swap my OPA627's with them for my DAC.
But I agree that the AD86x0series is a better choice nowadays.
Pitty they don't have them as DIL8's. So I could swap my OPA627's with them for my DAC.
thinking also of ordering the UCD400's. The thing is I just bought the NAD162/272 combination(2 months ago) so that was already some cash. Ah well.....you cannot stop progress and the UCD's keep coming up as a hot item to listen to/to have.
Life can be hard on you😉
Life can be hard on you😉
Sorry, I was thinking of the 637, not unity gain stable, I take it back. I wouldnt' bother replacing the 134 with it though, would you?
well my DAC has the OPA627's. Just ordered some AD8610's at Farnell to replace them. They were only € 5.74 p/p when ordering 10. Have to put them on a tiny PCB to be able to put them in a DIL8 socket.
Just want to know if they sound better. You're an audio freak or you ain't.
Just want to know if they sound better. You're an audio freak or you ain't.
Question about ground hum...
Of course I hope I won't have any in my system, but I have had trouble before (lots of equipment connected to a receiver, you know...)
Is using a ground isolator (1:1 transformer) in the signal a problem for UcD amps?
I know ground isolators have impact on sound, but I want to know if it is actually bad for the UcD input stage...
Of course I hope I won't have any in my system, but I have had trouble before (lots of equipment connected to a receiver, you know...)
Is using a ground isolator (1:1 transformer) in the signal a problem for UcD amps?
I know ground isolators have impact on sound, but I want to know if it is actually bad for the UcD input stage...
Shouldn't be a problem, and if you got a good, proper isolation transformer with a centre tapped (balanced) output then you can connect it in balanced mode to the UcD 🙂
I was wondering when we'll see the uCD700/1000? I'm working on a new subwoofer design that needs at least 500-watts of power in 4-ohms. I'm currently using the Thommessen SW6.0 amplifier which starts clipping if pushed to the limit.
If I look at the specs of the uCD400 module it will not handle the load and I have not seen any other digital amp that has a higher power rating. I'll just be using the amp, and a Thommessen Subway X active crossover to feed it.
Regards,
Sander Sassen
If I look at the specs of the uCD400 module it will not handle the load and I have not seen any other digital amp that has a higher power rating. I'll just be using the amp, and a Thommessen Subway X active crossover to feed it.
Regards,
Sander Sassen
SSassen said:
You can use two UcD400 modules in bridge configuration to get 800W in 4 Ohm, I plan to do that.
Gertjan
Note also that the UCD is 400W into 4 ohms... You can also look at the Zappulse modules which have a somewhat higher power rating for around the same price (and they sound pretty good as well). You can bridge those just like the UCD and get scary power levels...
You can't bridge a 4 ohm load on UcD400 and get 800W. The current limit on the UcD400 is 15 amps. With a 4 ohm load this equates to 900W peak, or 450W RMS.
As Ed has said, take a look at LC Audio ZAPpulse amps, they have oodles of power capacity.
As Ed has said, take a look at LC Audio ZAPpulse amps, they have oodles of power capacity.
richie00boy said:
Jan-Peter should confirm but as far as I remember the old one was 15 and the new 20 A.
Edit, found post 440 where JP lists the changes:
http://www.diyaudio.com/forums/showthread.php?postid=556560#post556560