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Twisted Pear Audio Opus DAC - Page 7

post #91 of 987
8/23/07 at 10:56am
Quote:
Originally Posted by johnsonad View Post
they felt that 30 watts should drive them just fine as they sell the speakers with a 39 watt tube amp.
Yeah I noticed that they marketed it with the rebadged Onix tube amp. I assumed that was because they don't carry a more powerfull amp. It's nice to know that the Strata is that efficient. I've been very interested in them for quite awhile before availability. How's the low end? I have two Rocket UFW-10's so it won't be an issue for me, just curious.

Quote:
Originally Posted by pabbi1 View Post
No, it will have a dedicated transport, like this:
I'm still considering that transport too. I purchased a PS Audio Lambda, that's built like a tank, but I think I may still pull the trigger on one of those. I'm waiting to hear more of Nate's impressions.
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post #92 of 987
8/23/07 at 4:04pm
Looks like they just got pre orders up and running. Just ordered mine
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post #93 of 987
8/23/07 at 6:19pm
Yep, ordered the Ballsie & Opus - but, they are out of the trafo... anyone know the RIGHT replacement for:

Avel Lindberg Transformer (115V+115V prim. / 15V+15V 25VA sec.)

is it this, or close enough?

http://www.partsexpress.com/pe/showd...number=122-605
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post #94 of 987
8/23/07 at 6:29pm
Quote:
Originally Posted by pabbi1 View Post
Yep, ordered the Ballsie & Opus - but, they are out of the trafo... anyone know the RIGHT replacement for:

Avel Lindberg Transformer (115V+115V prim. / 15V+15V 25VA sec.)

is it this, or close enough?

http://www.partsexpress.com/pe/showd...number=122-605
so, I've noticed this as well... there is no such thing as a 25VA toroid in the standard Avel Lindberg line. The 30 VA one will work and give you a bit more headroom. In fact, I may be placing an order with Avel directly for three 30 VA 15+15 and would be willing to pick one up for you and send it back with your transistors. Maybe we'll get a discount for four, who knows. Just send me an e-mail / PM.

Here's the entire Y23 Avel line here:

http://www.avellindberg.com/transfor...ange_specs.htm
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post #95 of 987
8/23/07 at 6:37pm
DigiKey carries the Amveco 70063 (TE70063-ND), a 15V+15V 25VA unit for $21.13 USD if you often order from them.
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post #96 of 987
8/23/07 at 8:43pm
The Avel number is Y236053. They only have 3 in stock (usually order 50). They have a ship date of "End of October" but have the 15VA version in stock (which is what we were originally going to carry). I'll probably get those instead, still plenty of extra power for an application that draws less then 500mA.
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post #97 of 987
8/23/07 at 9:12pm
Thread Starter 
I've picked up a full opus setup, including an usb board. I was going to pick up 4 more TPM modules to upgrade my TXO, but I have a few questions about that first
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post #98 of 987
8/23/07 at 9:23pm
Quote:
Originally Posted by BrianDonegan View Post
The Avel number is Y236053. They only have 3 in stock (usually order 50). They have a ship date of "End of October" but have the 15VA version in stock (which is what we were originally going to carry). I'll probably get those instead, still plenty of extra power for an application that draws less then 500mA.
I don't know what price you're getting from Avel, but the volume discount on the Amveco that DigiKey sells is pretty hefty. At an order of 50ct, they're $15 each, for the 25VA unit. It seems this is approximately inline with what you're listing them for on your site, so possibly an alternative if the smaller Avel isn't going to allow you to cut the price?
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post #99 of 987
8/24/07 at 1:08am
Quote:
Originally Posted by swt61 View Post
Yeah I noticed that they marketed it with the rebadged Onix tube amp. I assumed that was because they don't carry a more powerfull amp. It's nice to know that the Strata is that efficient. I've been very interested in them for quite awhile before availability. How's the low end? I have two Rocket UFW-10's so it won't be an issue for me, just curious.

The low end is tight and goes well beyond any bass I would ever need. As you know they have 300 watt internally powered subs built in. I really need to get an SPL meter to tune them in but with work for the next month, I barely have time to turn them on. PM Sleestack, he has a set too and can give you another opinion on them. It was through his system that inspired me to get mine. I can't speak for their efficiency with a sold knowledge but to me and Nebby, they sounded pretty damm good with the Aleph driving.
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post #100 of 987
8/26/07 at 4:01am
Did anyone build the Opus with an SPDIF input switch? Im considering doing this, but Im not sure if just using a rotary switch is good enough,
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post #101 of 987
8/26/07 at 9:11am
Mine has coaxial and toslink inputs, but in the interest of purity we decided to forgo a switch. I just won't pass both signals through simultaneously.
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post #102 of 987
8/26/07 at 10:47am
Hi guys,

New to this thread. Looking at the schematic of the OPUS,
it looks like the Wolfson Dac has output coupling caps (to filter
the DC)... Is this standard for a voltage output Dac?

Does not seem optimal for sound quality to have electrolytic caps in the signal path ...

Any thoughts?

Pete
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post #103 of 987
8/26/07 at 4:52pm
Quote:
Originally Posted by DigiPete
Hi guys,

New to this thread. Looking at the schematic of the OPUS,
it looks like the Wolfson Dac has output coupling caps (to filter
the DC)... Is this standard for a voltage output Dac?

Does not seem optimal for sound quality to have electrolytic caps in the signal path ...

Any thoughts?

Pete
Voltage out DACs normally have a DC offset of 2.5V. The common practise is to use an opamp to sum the two outputs, this will make the output single ended and automatically remove the DC offset. If you want balanced outputs the easiest is to use capacitors.
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post #104 of 987
9/3/07 at 7:55am
Quote:
Originally Posted by DigiPete View Post
Hi guys,

New to this thread. Looking at the schematic of the OPUS,
it looks like the Wolfson Dac has output coupling caps (to filter
the DC)... Is this standard for a voltage output Dac?

Does not seem optimal for sound quality to have electrolytic caps in the signal path ...

Any thoughts?

Pete
Or use the zapfilter or the discrete filter buffer stage on the DIYaudio CD63/67 mods thread.
The opus does look interesting though...

allan
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post #105 of 987
9/11/07 at 2:01pm
Greetings,
I'm very interested in this DAC. But wondering if/how "Ballsie" will decrease the sound-quality?! I've read a comment at the diyaudio-thread, that the only advantage of the OPUS is his balanced out ... so if you'll use the Ballsie it's quite unspectacular/worthless. What do you think? - Is the Opus still interesting if you'll use unbalanced out?

Best regards,
bearmann
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