[Rensek]

Could it be ran off a variac?

https://m.vevor.com/variable-transf...ormer-with-lcd-digital-display-p_010643684379

 

[adias]

Freya S use relay ladder resistor as volume control, NAD could be using an attenuator something like Alps RK27, if so, they behave differently.

For example, if I feed 2V to the RK27, at (roughly) 10 o'clock it is 0.1V, 12 o'clock is 0.33V, 2 o'clock is 1V... I do not know the voltage of Freya at certain position because I don't own one, may be Jason or other members can tell.

I measure it by putting a noise signal to the Modi multibit 2, it output 2V, and measure the voltage after the RK27 attenuator at different position to get the idea, of course you need an AC voltmeter.

NAD can be difficult because it is an intergrated, you need to open it, and it is risky with live power line voltage.

I know all about Freya’s ladder resistor attenuator. I own both a Freya S and a Kara. My comment has to do with the fact that the RP-600M is 96 dB sensitive. I used to use this pipeline Freya S/Vidar 2 with 86dB sensitive Maggies and for moderate listening the ladder resistor attenuator knob was roughly in the same position. And the ladder step is something like 0.6dB. Anyway I found that interesting.

 

[r2muchstuff]

Sorry to post a completely non-Schiit related question here, but I thought that I'd take advantage of the impressive technical knowledge regularly on display in this forum: Does anyone have any experience using amplifiers from the domestic Japanese market in the US? I was recently in Tokyo and visited a couple of shops in Akihabara and they didn't recommend buying an amp in Tokyo and bringing it to the US due to the voltage difference: Japan domestic outlets provide a constant 100V voltage, whereas in the US we have 120V +/- 6%. Apparently, the amplifiers made for the domestic Japanese market are designed for 100V constant voltage and the dealer didn't recommend using it in the US. My guess is that the input stages are fed by regulated power supplies so they should be OK, but the output stage power supply may well be unregulated, which would increase the voltage by 20% (and power by 44%) so I guess the risk is frying the output stage. Any advice from all you fine and knowledgeable folks? (Why buy in Tokyo you ask? To which I say: Have you checked the USD/JPY exchange rate lately?)

I have a rack of vintage Pioneer which includes an Exclusive M3 Amp. It is domestic Japan market amp. I bought a transformer to power it. Many years of use; never had any issues.

 

[r2muchstuff]

Also, Japan has 50 & 60 Hertz power. Check which one the amp requires or if will it work with either. My transformer provides 50 for the Exclusive M3.

 

[Ohno Schiitizen]

I know all about Freya’s ladder resistor attenuator. I own both a Freya S and a Kara. My comment has to do with the fact that the RP-600M is 96 dB sensitive. I used to use this pipeline Freya S/Vidar 2 with 86dB sensitive Maggies and for moderate listening the ladder resistor attenuator knob was roughly in the same position. And the ladder step is something like 0.6dB. Anyway I found that interesting.

I see, Freya S and Kara with same ladder resister volume control.

Yes, that is interesting, the 600M should need less power according to the sensitivity .... may be the impedance are different 4 vs 8 ohms?
Also 86dB / 500Hz / 2.83v ... is the 500Hz frequency at the spec makes a different, I do not know either ..

 

[tincanear]

old-skool transformers have output at same frequency as input.

Using Japan domestic-market 100V devices with US 120V mains is nominally a 20% overvoltage condition, worse if your local power runs a bit above the 120V. Looking at a subset of design considerations:
transformer core saturation possible but unlikely for this usage case;
PSU main filter caps will see the overvoltage, OK with adequate design margin;
linear voltage regulator circuits will have increased power dissipation--
e.g. 20V unregulated rail, 16V out means 4V drop across the regulator; with 20% mains overvoltage condition, unreg rail rises to 24V, now 8V regulator drop, so twice the nominal power/heat must be dissipated by the regulator/ heatsink.

Better to use a proper 120V-to-100V step-down transformer of ample wattage / VA rating (recommend 150% to 200% the expected load here for cooler running / longer life with the propensity of off-shore brands to exaggerate specs). Variac can also be used, but with caution: many of these can be (acciddentally) dialed up to 120% or 125% of input, a bump or twist of the dial might let the magic smoke out, and shipping/ repair cost might be $$$.

 

[Ohno Schiitizen]

There is a brand name, MATSUNAGA, product name STAVOL , they make auto transformers, may be you can check it in Japan, a well known and reliable product.

Something like this: https://www.ebay.com/itm/323975988050
or this: https://www.ebay.com/itm/255065067133

Another option: https://www.amazon.ca/120V-100V-Con...B07L56PYZS/ref=pd_ci_mcx_pspc_dp_d_1_t_1?th=1

 

[R3DFIV3]

... Plenty of petting, aren't breasts fantastic?

 

[nojwe]

Probably a dumb question, but what’s the difference between the Yggy GS2 and current OG? The specs appear to be the same

 

[NewSchiithead]

Probably a dumb question, but what’s the difference between the Yggy GS2 and current OG? The specs appear to be the same

The GS2 has the older Analog 1 card, the OG has an Analog 2.

 

[nojwe]

The GS2 has the older Analog 1 card, the OG has an Analog 2.

I should have phrased that better. What’s the difference between the two analog cards?

 

[adias]

I should have phrased that better. What’s the difference between the two analog cards?

---

Edited: My mistake

 

[Ripper2860]

The Yggy GS2 has the A1 card and according to the GS2 spec page...

Analog Stage: Fully discrete, DC coupled Class A FET buffers optimized for high current output and fully discrete, Class A FET summing stages for single-ended output

A2 is fully discrete, as well. LIM and MIB use op-amps.

 

[Daniel Johnston]

A2 has a fully discrete analog output stage. There may be more differences.

A1, LIM, MIB have opamp audio stages.

A1 was discrete. Jason improved everything with A2. No op amps.

 

[adias]

A1 was discrete. Jason improved everything with A2. No op amps.

Thanks for the correction.