John Curl's Blowtorch preamplifier part II

[Destroyer OS]

I agree with Richard that jitter is probably the biggest contributor to CD problems in recent years. We don't have much control over commercial recordings, and they probably take every short-cut possible, but there are hi end companies who take great care with their high definition mastering as well as their studio recording equipment, and this is often the source of quality hi res recordings. Here is where the 'better' sound systems can show their stuff.

Good thing you're the amp guy 😛

 

[jneutron]

Never seen a breaker that doesn't use one frame for all ratings so they take whatever fits.

That may or may not be correct. Just a caution..

I looked at mine they say Al-Cu and come with a data sheet that tells which panels they fit and 1 phase 3 wire 120/240V 10KA interrupt.

Does the data sheet indicate which brand the breakers are approved for? I was surprised to find that sometimes, even if the breaker fits, it may not be approved for use.

No issue with the bonding, there are terminals on the rack and each piece of gear is rated.

I didn't say there was. Only why a code inspector might be interested in looking under the hood.

No the guy worked in the trades and knew the 40% rule from pulling runs. I did cite chapter and verse. The current code has a nice bit about heating and fill and 40% as a guideline.

What is current code? 2014, 2011, or 2008? States typically take 3 years to adopt new. I can see you running into issues depending on the install location.

You really should reread section 1 where it describes where the code comes into play. There are lots of exemptions for my kind of stuff.

Coming across with such a poor attitude like that is probably why the guy gave you problems. You just told me that I don't know what I'm talking about and I should go back and study the subject because you are ""above the law"". If you change your attitude, you'd probably have less "this happened to me" stories about code.

John

 

[SY]

"Hubbell" not "Hubble." They're customers of mine.

 

[bcarso]

"Hubbell" not "Hubble." They're customers of mine.

Thanks. I was tempted to make that correction---but my reputation as a grammar nazi is already troubling.

 

[jneutron]

"Hubbell" not "Hubble." They're customers of mine.

Well, Hubble is one of my customers. Looking for a field trip..bringin my lens cleaner wipes..


In space, they can't hear you squeegee..


John

 

[SY]

I perform the Klingon ritual in airlocks.

 

[Destroyer OS]

I perform the Klingon ritual in airlocks.

Until your mother comes downstairs to do laundry and you pretend you're taking a nap?

 

[simon7000]

That may or may not be correct. Just a caution..




Does the data sheet indicate which brand the breakers are approved for? I was surprised to find that sometimes, even if the breaker fits, it may not be approved for use.


I didn't say there was. Only why a code inspector might be interested in looking under the hood.


What is current code? 2014, 2011, or 2008? States typically take 3 years to adopt new. I can see you running into issues depending on the install location.


Coming across with such a poor attitude like that is probably why the guy gave you problems. You just told me that I don't know what I'm talking about and I should go back and study the subject because you are ""above the law"". If you change your attitude, you'd probably have less "this happened to me" stories about code.

John

Actually never met the guy. We ship the system and the subcontractor on site handles those things. Normally I sit down withe the AHJ and hand them a cut sheet book and my read of the appropriate code sections. Even yeàrs later they treat me well.

Most of them know they have never seen A sound system of my size and appreciate the review. Fire marshals also get a view of the STI techniques.

SY wow you are right. Mispllleld it this time.

 

[billshurv]

Not sure why, but this all feels fairly oddparents 🙂

Hey I have 5 kids..

 

[Max Headroom]

I don't like the grainy, harsh sound of live music.
The other problem with it, is a lot of the gear has ferrites in it - especially those bass amps that use class D. You can hear it.

Agreed.

Dan.

 

[31697B]

Data to support that claim?

I am surprised you ask.... Google - Jitter in DAC. Or similar. Talk to ADC/DAC designers... like BenchMark. Benchmark told me Jitter and analog were the main causes of differences. And, finally, measure some jitter spectrum results yourself. you can buy/rent jitter analyzers. I have.


THx-RNMarsh

 

[SY]

OK, so no data.

 

[Bonsai]

I do recommend anyone who likes classical to try the UK based Chandos label. As they record 5.1 channel SACD and mix down to 2 channels for the CD layer/download you don't get the rolled off lower octaves that most commercial recordings have. And it's music you want to listen to!

Some labels who should know better have some very odd frequency responses that suggest a lot of post processing.

Question - why are the lower octaves rolled off? I see no reason for this on a CD or digital recording.

I have some CD's with 'seismic' bass, but many leave a lot to be desired I would agree.

I've been thinking about getting a sub . . .

 

[billshurv]

Question - why are the lower octaves rolled off? I see no reason for this on a CD or digital recording.

Guessing so it doesn't kill the average wimpy speaker. But it's oddly close to a vinyl roll off in bass...

Correlation is not causality but two attached examples. One is a chandos SACD and the other is another label redbook only. My assumption is that SACDs are mastered for the .1 sub channel. But really should write to chandos and ask them. EDIT: I believe the infrasonics are an anomaly due to unfamiliarity with audacity.

I've been thinking about getting a sub . . .

Had one for 18 years. Just never got it running. Bad me!

 

[31697B]

OK, so no data.

Correct. No data for you from me.
.

THx-RNMarsh

 

[31697B]

Question - why are the lower octaves rolled off? I see no reason for this on a CD or digital recording.

I have some CD's with 'seismic' bass, but many leave a lot to be desired I would agree.

I've been thinking about getting a sub . . .

Many CD's have long been made off the "2nd Gen master" made for cutting LP's. Not from the original master.


THx-RNMarsh

 

[SY]

Correct. No data for you from me.

Yes, empty claims are always the best claims.

 

[31697B]

Right SY. I'll tell BenchMark that, too.

Wouldnt for you even if I was not sitting on the balcony looking out from my 30th floor loft here in Bangkok.
Going to go out and eat dinner now (6pm here).

THx-RNMarsh

 

[billshurv]

back in the 80s maybe, but an awful lot were remastered for CD as well. Still not sure where this great improvement is coming from.

 

[billshurv]

Intriguingly stereophile doesn't seem to test sampling rates above 44.1 other than frequency response but does test 24bit operation. I can only thing that the AP they have doesn't support things, unless there is something they want to hide?