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A wishlist of gear to be reviewed by Amir

bigx5murf

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#61
Considering how the oppo conquers all. I'd love to see how comparable BD player compare. Or maybe even HD-DVD players since those are practically worthless. I recently started playing CDs with my Toshiba HD-A1 and was pleasantly surprised by the SQ. Although the boot time on this things is kind of long.
 

Voo

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#62
does this site test any microphones for recording? I would like to get some type of recommended value system to record my home stereo from 10-20k hz...when looking for info I find either studio or vloggers/youtube info.
 

DDF

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#63
It would be great to see Nuprime amp or DAC measured. There are no measurements on line but many magazine evaluations are praising them.

Nuprime claim superiority of their amps by using an extremely high switching frequency. It would be interesting to see the premise tested.

Their DAC10 uses a novel analog volume control method that I've only seen used in Pass gear and the headphone amp is supposed to be a power house. Full disclosure, I have both an IDA-8 and DAC10H so this suggestion isn't purely academic. :)

In general for DACs it would also be helpful to see measurements of USB isolation but I can appreciate this would be difficult for Amir. Some DACs are very susceptible to ground loops over the USB. I had to change my music lap top to a doubly insulated power supply with no earth ground, in order to avoid bit hits on my dacs. I'm surprised that so many "high end" dacs don't use transformer coupled inputs. In the mid 90s I converted my Sony CD player to add an spdif coax output using a coupling transformer and logic chip, and it cost a few bucks back then and killed a $1k Denon player's digi out on the lab scope. This shouldn't be beyond the capabilities of manufactures to do cheaply.
 

amirm

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#64
does this site test any microphones for recording? I would like to get some type of recommended value system to record my home stereo from 10-20k hz...when looking for info I find either studio or vloggers/youtube info.
No, we don't do any microphone testing. We do have a number of people who have studios and/or record live music. So create a new thread and ask. I will ponder testing microphones for the future. :)
 

amirm

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#65
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#68
Something like the Stax SRM1 Mk2 would be interesting to see. But is that even possible for the Audio Analyzer? The Output should differ a lot from normal headphone amps.
 

amirm

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#69
Something like the Stax SRM1 Mk2 would be interesting to see. But is that even possible for the Audio Analyzer? The Output should differ a lot from normal headphone amps.
It is on my todo list to measure my three Stax amps. They are much older than current ones but will give us some data points. I will need to build a safe connector that avoids the high voltage bias.
 

RayDunzl

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#70
I will need to build a safe connector that avoids the high voltage bias.
The signal voltage is high, too, is it not?

How do they compare?
 

amirm

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#71
The signal voltage is high, too, is it not?
Yes although I don't know how high. My AP analyzer can accept up to 150 volts. If they are higher than that, I have a differential probe with 10:1 attenuation I can use. I am going to instrument it with my scope and this probe first before performing any measurements.

Alternatively I can open the box and go before the transformers.
 

amirm

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#72
How do they compare?
How does what compare? The amps I have? If so, one is solid state. The other two are tube. One is single-ended and the other balanced.
 

RayDunzl

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#73
How does what compare?
The bias and signal voltages.

You mentioned being wary of the bias voltage.

The signal voltage may be quite high too.

One schematic I looked at seemed to indicate 450Vrms for the signal.

On the panel speakers, my schematic is not marked, but elsewhere a 100:1 step-up signal transformer was discussed. That may be high, but...
 
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RayDunzl

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#74
Alternatively I can open the box and go before the transformers.
I didn't see output transformers on the Stax/Clone schematics.

Anyway, I might expect high signal voltages at "full scale" in addition to the known expectation for tthe bias voltage.

---
Stax 727 II specs
Max. Output Voltage: 450V r.m.s. (1kHz)
 
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#76
It is on my todo list to measure my three Stax amps. They are much older than current ones but will give us some data points. I will need to build a safe connector that avoids the high voltage bias.
Good to know! I am just curious if they Line Outs on these devices are any good, or if they affect the signal in any way.
 

amirm

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#78
Did you find it? I have one also. Very interesting how it measures.
Yes I did. It is a pretty solid little device mechanically. I will see if I can review it quickly....
 

amirm

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#79

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