Is there a better bargain than the $56 Nobsound Passive Preamp?

sumoking · « **Reply #20 on:** 26 Dec 2018, 04:18 pm »

Quote from: Speedskater on 26 Dec 2018, 02:24 pm

Gee, $56 for the linked Nobsound unit is a great deal for a balanced stereo level control. I'm temped to get one just to see if it's wired correctly.
It's easy to mis-wire a balanced level control and when you add XLR to RCA switches at both ends, why it's even easier.

I can assure you that mine is wired correctly. A balanced passive preamp that sounds fantastic for $56 is amazing. I can't wait to read the comparison reports. I love the passive cause its clean. To put tubes in the mix defeats the purpose of the passive and the resulting transparency you get in my opinion. I haven't had an issue with the RCA inputs.
Question: Since this is so inexpensive, does it make any sense to get two and use them in a dual mono fashion? I know you have to adjust two volume controls, but would it sound any better?

OzarkTom · « **Reply #21 on:** 26 Dec 2018, 04:48 pm »

Quote from: sumoking on 26 Dec 2018, 04:18 pm

Question: Since this is so inexpensive, does it make any sense to get two and use them in a dual mono fashion? I know you have to adjust two volume controls, but would it sound any better?

As good as it sounds now, why buy another? But you can always return it to Amazon if it does not work.

My only complaint is the very sensitive volume control. But at $56, why complain? Maybe they will someday make a remote control version. But that might take away from the SQ like Rex's $1400 passive.

mr_bill · « **Reply #22 on:** 26 Dec 2018, 05:57 pm »

Not sure if I understand how a passive pre that doesn’t have power works... ......can I hook a phono stage to it and control volume just like a regular Preamp?

Poultrygeist · « **Reply #23 on:** 26 Dec 2018, 06:59 pm »

This is the Nobsound I have. Hard to figure out which Nobsound passive was the subject of this thread. This one requires power for the switch only and has three inputs and two outputs. One output is volume controlled while the other is straight through. For whatever reason this site won't ( at the moment ) allow my pictures to load. Here's a link.

https://www.amazon.com/Nobsound-Selector-Pre-Amplifier-Adjustable-Controller/dp/B01M18QM62/ref=sr_1_9?ie=UTF8&qid=1545850090&sr=8-9&keywords=Nobsound+passive+preamp

orientalexpress · « **Reply #24 on:** 26 Dec 2018, 07:01 pm »

Quote from: mr_bill on 26 Dec 2018, 05:57 pm

Not sure if I understand how a passive pre that doesn’t have power works... ......can I hook a phono stage to it and control volume just like a regular Preamp?

it's only work with solid state phono ,not tubes phono stage.

rollo · « **Reply #25 on:** 26 Dec 2018, 07:43 pm »

Quote from: sumoking on 26 Dec 2018, 04:18 pm

I can assure you that mine is wired correctly. A balanced passive preamp that sounds fantastic for $56 is amazing. I can't wait to read the comparison reports. I love the passive cause its clean. To put tubes in the mix defeats the purpose of the passive and the resulting transparency you get in my opinion. I haven't had an issue with the RCA inputs.
Question: Since this is so inexpensive, does it make any sense to get two and use them in a dual mono fashion? I know you have to adjust two volume controls, but would it sound any better?

Like that idea of two for dual mono. Yes two volume controls but adds benefit of balancing both channels if needed. For me personally dual mono everything has been much better than anything else.

charles

wushuliu · « **Reply #26 on:** 26 Dec 2018, 08:48 pm »

Quote from: mr_bill on 26 Dec 2018, 05:57 pm

Not sure if I understand how a passive pre that doesn’t have power works... ......can I hook a phono stage to it and control volume just like a regular Preamp?

It's just a volume pot with inputs and outputs. That's what a 'regular' preamp is ultimately, without bells and whistles. You can hook up whatever you like as long as you remember that a passive doesn't add gain. It attenuates what comes in, it doesn't increase it.

wushuliu · « **Reply #27 on:** 26 Dec 2018, 08:54 pm »

Quote from: Poultrygeist on 26 Dec 2018, 06:59 pm

This is the Nobsound I have. Hard to figure out which Nobsound passive was the subject of this thread. This one requires power for the switch and has three inputs and two outputs. One output is volume controlled while the other is straight through. For whatever reason this site won't ( at the moment ) allow my pictures to load. Here's a link.

https://www.amazon.com/Nobsound-Selector-Pre-Amplifier-Adjustable-Controller/dp/B01M18QM62/ref=sr_1_9?ie=UTF8&qid=1545850090&sr=8-9&keywords=Nobsound+passive+preamp

As Tom mentioned, the subject of this thread is the one that uses no power and has a 10k volume pot.

Folsom · « **Reply #28 on:** 26 Dec 2018, 09:06 pm »

Why I don't make one is because I'd have to order from China. I'm going to want to much $ if I make it. There just isn't a way to compete, and people will probably be disappointing that they don't get something real fancy once they start paying more $. I recommend just building your own. It can't get much easier.

Here's one you can build.

Here's an assembled one.

Their volume devices is so superior. It's why I'd throw anything Alps in the trash.

wushuliu · « **Reply #29 on:** 26 Dec 2018, 09:25 pm »

Quote from: Folsom on 26 Dec 2018, 09:06 pm

Why I don't make one is because I'd have to order from China. I'm going to want to much $ if I make it. There just isn't a way to compete, and people will probably be disappointing that they don't get something real fancy once they start paying more $. I recommend just building your own. It can't get much easier.

Here's one you can build.

Here's an assembled one.

Their volume devices is so superior. It's why I'd throw anything Alps in the trash.

The cheap SMD DACT-copy pots in the Tisbury are only $12 and yes, they are *excellent*, but the Nobsound is cheap and cheerful set it and forget it. Hopefully Nobsound will make a DACT version like Tisbury.

Folsom · « **Reply #30 on:** 26 Dec 2018, 11:19 pm »

If they did I might have one just for circumstances that come up.

Cacophonix · « **Reply #31 on:** 26 Dec 2018, 11:44 pm »

Quote from: wushuliu on 26 Dec 2018, 09:25 pm

The cheap SMD DACT-copy pots in the Tisbury are only $12 and yes, they are *excellent*, but the Nobsound is cheap and cheerful set it and forget it. Hopefully Nobsound will make a DACT version like Tisbury.

Looks like nobsound does have a stepped attenuator version
https://www.amazon.com/Nobsound-Potentiometer-Preamplifier-Attenuator-Preamplifiers/dp/B076BP2QM6

Just doesn't seem to have as much feedback anywhere.

maplegrovemusic · « **Reply #32 on:** 27 Dec 2018, 12:16 am »

At these prices one can try a dozen different ones and still be way under what a low priced "midfi" preamp sells for

wushuliu · « **Reply #33 on:** 27 Dec 2018, 12:28 am »

Quote from: Cacophonix on 26 Dec 2018, 11:44 pm

Looks like nobsound does have a stepped attenuator version
https://www.amazon.com/Nobsound-Potentiometer-Preamplifier-Attenuator-Preamplifiers/dp/B076BP2QM6

Just doesn't seem to have as much feedback anywhere.

That's the kind with the switching resistors:

So many preamps/pots out there. Glad they're finally getting packaged though, for a long time these options were just diy.

Folsom · « **Reply #34 on:** 27 Dec 2018, 12:38 am »

Low noise switches (relays) are not that cheap.

It would be nice to know what stepped attenuator is used. The blue ones with a white cap sound terrible.

sumoking · « **Reply #35 on:** 27 Dec 2018, 02:34 am »

Quote from: Folsom on 26 Dec 2018, 11:19 pm

If they did I might have one just for circumstances that come up.

I used to have Reference Line Pre Emenience Dual Mono Preamp which was very transparent.

Folsom-
Do you make passive preamp's. If it was a lot better sounding than my nobsound, I would consider purchasing a top notch passive with two single ended RCA and one XLR input; two XLR and one single ended outputs.
How much would you charge to make it?
Curious, Many thanks.

lacro · « **Reply #36 on:** 27 Dec 2018, 04:30 pm »

This thread is timely as it encourages me to finally put this together. I have had the board, and parts for awhile. I will be using a stepped attenuator in place of the Alps pot.

https://www.diyaudio.com/forums/group-buys/291429-gb-salas-select-mesmerize-type-input-selector-volume-control.html

rollo · « **Reply #37 on:** 27 Dec 2018, 04:34 pm »

Ordered one to use for burn in purposes. Of course I will give it a go in main rig out of curiosity. For $56 no need to use my preamp to burn in cables.
Please remember passive preamps do not fit all systems. For optimum performance the source [ CD/DAC ] requires a minimum of 2V output. The more the merrier. Then ones Amp should have a low input sensitivity. They will work without these requirements however not their best.
I have owned several passive designs. Promithius, Stevens & Billington which are transformer based. As well as several other resistor based ones. I prefer the transformer based.
For $56 again well worth a spin. Let ya know what I hear. Will be comparing to a Lamm LL2.1 preamp. Yes unfair but informing.

charles

OzarkTom · « **Reply #38 on:** 27 Dec 2018, 05:13 pm »

Quote from: rollo on 27 Dec 2018, 04:34 pm

For $56 again well worth a spin. Let ya know what I hear. Will be comparing to a Lamm LL2.1 preamp. Yes unfair but informing.

charles

That will be interesting Charles. Probably one of the most unfair comparisons anyone can make.

sumoking · « **Reply #39 on:** 27 Dec 2018, 05:21 pm »

Quote from: rollo on 27 Dec 2018, 04:34 pm

Ordered one to use for burn in purposes. Of course I will give it a go in main rig out of curiosity. For $56 no need to use my preamp to burn in cables.
Please remember passive preamps do not fit all systems. For optimum performance the source [ CD/DAC ] requires a minimum of 2V output. The more the merrier. Then ones Amp should have a low input sensitivity. They will work without these requirements however not their best.
I have owned several passive designs. Promithius, Stevens & Billington which are transformer based. As well as several other resistor based ones. I prefer the transformer based.
For $56 again well worth a spin. Let ya know what I hear. Will be comparing to a Lamm LL2.1 preamp. Yes unfair but informing.

charles

Will be interesting to hear your comparison results. It would be even more interesting to hear how it compares to a Tortuga (or similar) if anyone has one.
Sumo