Dedicated Stereo/Audio/Video thread

[Sandy H.]

Not going to derail this into a 'cable thread' (audio version of a glue thread) but those cables do look nice. I like well built stuff.

Having said that, Marty, you have an unhealthy obsession with bass. I never heard real bass until I went to an NHRA event. I heard it the second time in your listening room and that was nothing like this stuff. You need help. As a friend.

(fyi, my wife probably couldn't live within 2 miles of a system like that. She's audibly sensitive to both lows and highs, so you can guess what my audio hobby is like now. . . .)

Sandy.

 

[hobie1dog]

Stereo Integrity fat roll surround subwoofer, extremely tight Bass

 

[FredA]

I never got to hear an all Levinson system

I just "broke" mine up by inserting a miniDSP SHD in the balanced path between my No 26 and my No 23.

Got the SHD yesterday.
Wired it up and programmed it for basic XO duty which was has been an issue since I got my SB16-Ultra.
Sounds nice so far, but no time for any critical listening.
Now need to get working on the DIRAC calibration and turn that on.

But yea - Levinson gear is the bomb.
And yes, due to the CAMAC connectors, I've got crazy expensive interconnects.

 

[Sandy H.]

Not going to derail this into a 'cable thread' (audio version of a glue thread) but those cables do look nice. I like well built stuff.

Having said that, Marty, you have an unhealthy obsession with bass. I never heard real bass until I went to an NHRA event. I heard it the second time in your listening room and that was nothing like this stuff. You need help. As a friend.

(fyi, my wife probably couldn't live within 2 miles of a system like that. She's audibly sensitive to both lows and highs, so you can guess what my audio hobby is like now. . . .)

Sandy.

Why sad?

 

[hobie1dog]

Why sad?

that you're not able to have two 18-in subwoofers and a volume control that goes up to 11

 

[Sandy H.]

that you're not able to have two 18-in subwoofers and a volume control that goes up to 11

Fair enough. I do like the idea, but her hearing issues are more important. We're actually going to look at buying a different car, as she gets headaches from the CVT sound of he current ride. Lame for sure, but if you're going to get a headache driving your car, it had better be a badass car. Hers is not. . .

Sandy.

 

[OverTheTop]

You guys are inspiring me to get my amps out and put my system back together when I get the new house built. I guess I had better build some decent speakers to go there as well. I have never had a decent pair of speakers, but the amps I built are really quite good.

 

[tsmith1315]

I guess I had better build some decent speakers to go there as well

I can’t wait to see that!

 

[hobie1dog]

I guess I had better build some decent speakers to go there as well. I have never had a decent pair of speakers, but the amps I built are really quite good.

95% of the entire sound quality of the system will be based upon how good your speakers are.

 

[cvanc]

FredA, which microphone did you get with the SHD?

My SHD is older so it came with the UMIK-1. A year or so later UMIK-2 became available and I picked one up. My personal opinion is the UMIK-2 does a much better Dirac calibration.

Enjoy!

 

[FredA]

FredA, which microphone did you get with the SHD?

My SHD is older so it came with the UMIK-1. A year or so later UMIK-2 became available and I picked one up. My personal opinion is the UMIK-2 does a much better Dirac calibration.

Enjoy!

Got the UMIK-2 - glad to hear it was the proper choice.
Just getting it out of the box. Play time ahead.

 

[jderimig]

Finally (18 month project) got the second speaker built. I have never heard such clear and glorious midrange. Voices are to die for. Still only have about 12 hours on the drivers so still probably breaking in. Troels says pro-drivers take a little longer to break in because their surrounds are more beefy. I get all the volume that I want all of them out of my 6-7 watt SE amp. I think my next winter project is to build another SE amp with a little more output, 12-15W. Looking at some candidate topologies now. Picture below was in a dark room trying to get the tube glow with my cheap cell phone camera. Fail.

 

[hobie1dog]

They turned out nice.

 

[OverTheTop]

I get all the volume that I want all of them out of my 6-7 watt SE amp. I think my next winter project is to build another SE amp with a little more output, 12-15W.

Do you have a link to the amp you built? Curious for a look.

 

[jderimig]

Do you have a link to the amp you built? Curious for a look.

This is the original circuit from which it is based. I used solid state rectifiers for the power supply.


From there it was tweaked abit. I added a bypass capacitor on the screen of the output tube. And I have added global NFB from the output transformer to the cathode of the drive tube which I can switch on and off. To my ears I prefer it switched off. There is a long thread here on its evolution with help from the experts.

Schade P2P and gNFB in RH807

With the help of @Baudouin0 I have added gNFB to the RH807 amp as shown below. I left the original 100K Schade plate to plate feedback in while adding the 2.2K gnfb resistor. My question is there any rule of thumb on the balance between Schade and gNFB that should be used? Or is done by ear...

www.diyaudio.com

 

[OverTheTop]

Thanks for that. I'll have a read and learn some things. I won't be building one though as I prefer the low distortion of MOSFET amplifiers. I have a nice one I built back in the '80s, 100W per channel.

 

[jderimig]

I prefer the low distortion of MOSFET amplifiers.

Have you ever heard a low distortion SE class A pentode or triode?

 

[OverTheTop]

Have you ever heard a low distortion SE class A pentode or triode?

No, but the idea of having extra distortion, provided by the amp, doesn't sit well with me. The amp I have is THD<0.005% so is pretty clean.

 

[hobie1dog]

Uh Ohhhhh, distortion discussion about to erupt

 

[jderimig]

Uh Ohhhhh, distortion discussion about to erupt

I won't start it. Resist, resist.....

 

[tsmith1315]

I have never heard such clear and glorious midrange. Voices are to die for

Thanks for the early impression.

 

[hobie1dog]

years ago one of the stereo magazines did an article on a university who did a double blind test with 40 students that were considered to be audiophiles. they wanted to see at what level they could detect distortion. only five of the 40 could detect distortion in the 3 to 5% range and all the others took greater than 5% to be able to detect it. 2% or less Distortion couldn't be detected by any of them.

 

[FredA]

Nice looking speakers John - a warm velvet midrange is what counts IMHO, so congrats.
I see a pair of stands in your future.

 

[Sandy H.]

Have you ever heard a low distortion SE class A pentode or triode?

No, but the idea of having extra distortion, provided by the amp, doesn't sit well with me. The amp I have is THD<0.005% so is pretty clean.

Personally, I believe the best idea is to have one of each and to see what makes me smile more on any particular song. Audio is almost an anti-glue thread for me much of the time. The best answer is either both or all of them!

Sandy.

 

[hobie1dog]

I've heard all different kinds of amplifiers and preamps through the years, but the thing that makes the most difference and determines 90% of your sound quality, is going to be the final transducer, yes the speakers.

 

[jderimig]

I've heard all different kinds of amplifiers and preamps through the years, but the thing that makes the most difference and determines 90% of your sound quality, is going to be the final transducer, yes the speakers.

Yes and the 'best' speakers measure horribly as far as THD, phase response etc. A real s**t show.

 

[jderimig]

years ago one of the stereo magazines did an article on a university who did a double blind test with 40 students that were considered to be audiophiles. they wanted to see at what level they could detect distortion. only five of the 40 could detect distortion in the 3 to 5% range and all the others took greater than 5% to be able to detect it. 2% or less Distortion couldn't be detected by any of them.

My amp has switch to turn global NFB on and off. Off I use about 8db of internal output to driver feedback, switch on switches another 8db or so global feedback from the transformer secondary to the driver. Switch on measures better as expected, lower THD and more extended FR (which I can't hear anymore but thats an aside).

Now that I have better resolving speakers I did another comparison. I was enjoying Fleetwood Mac Tango in the Night. On the first track, Big Love, I heard a very audible difference. Tonality was identical. With GNFB off Lindsay's voice was very precisely imaged with a nice subtle 3D quality. When GFNB was switched on the depth quality in his voice was mostly lost and the imaging was lost a bit. Almost like a slight smearing from left2right. It was subtle but clear.

Edit: Best description is with NFB off I heard a head, with NFB on I heard a mouth.

Was the better imaging (and enjoyment) the result of some distortion product? Perhaps. But I am leaving the switch off for now.

 

[jimzcatz]

Anyone here that can fix a plate amp on my sub. It's working fine then pops and goes into standby. I believe it's the signal switch.

 

[jderimig]

So I am thinking (usually means trouble) of seeing if there are any improvements audible of using the balanced outputs of my DAC. Currently I run interconnects from the SE output of my DAC to a stepped attenuator then directly to my amp which is SE input.

What I am thinking is to run balanced cables from the DAC to a line transformer (link below) to the stepped attenuator and eventually put all that inside the amp chassis. The main attraction to me is the DAC puts out almost 4V at the balanced outputs which will make the amp much easier to drive. Plus I can run longer interconnects and locate the amp closer to the speakers with shorter speaker cables.

Loading…

www.jensen-transformers.com

 

[tsmith1315]

Sounds like fun! I’d predict the increased voltage to have an obvious effect, but sonic differences to be primarily influenced by the transformer.