[foreverzer0]

One of these factors is output impedance. The HA-501 has a damping factor knob, which adjusts the amp's OI for use with a specific headphone. It could have been set really high when you tested it. Just guessing here...

However, the hd650 he tested it on is fairly high already. Plus wouldn't OI more so affect the frequency response versus volume/power?

 

[Josef Parran]

However, the hd650 he tested it on is fairly high already. Plus wouldn't OI more so affect the frequency response versus volume/power?

Yes. According to a rather smart "guy" that was around a few years ago, high output impedance matters for 3 reasons:

1. The greater the output impedance, the greater the voltage drop with lower impedance loads. This drop can be large to enough to prevent driving low impedance headphones to sufficiently loud levels.
2. The greater the output impedance, the greater the frequency response deviations.
3. As output impedance increases, electrical damping is reduced. The bass performance of headphones may be audibly compromised if there’s insufficient damping.

But yeah, if he tested with the HD 650 then it's something else. I thought he might have been referring to the 80 ohm version of the DT 250.

 

[RSC08]

For those that own the UD-505, how is it in terms of dynamics? Also, does it have a black baground?

 

[r0ss1992]

I've paired the Teac with Beyer T1.2 and I'm listening to them in balanced mode, a necessary choice with the extremely high Beyer's impedance. I think that this dac is overly underrated, and its headphone amplifier is a good discrete class AB amp that can drive any dynamic Headphone on the market. For planar magnetics the max output amperage(500mA) is a bit low, maybe. Beside the headphone output voltage is good for a dac first machine.
Teac has know how, the exceptional technical specifications of a lot of dacs that we can buy in the last years (Topping, SMSL etc..) don't tell us all of the story. IMHO. Ok digital is digital and Dac chips are Dac chips, but output stages? Clock? Construnction quality? Power supply quality? Here we have dual toroidal transformers and a top notch quality construction, with 3 support feets, a completely dual monaural structure and analog circuit totally separated from the digital one.
Good listening

 

[r0ss1992]

P.S. I've tried T1.2 in active ground mode too and I think that the Teac makes them much more fast in transients, mostly in some genres like metal, rock and hard rock. It adds much instruments separation and a cleaner scene presentation. The doubled voltage power output of balanced mode helps when you need more presence and incisiveness of the instruments.

 

[runssical]

P.S. I've tried T1.2 in active ground mode too and I think that the Teac makes them much more fast in transients, mostly in some genres like metal, rock and hard rock. It adds much instruments separation and a cleaner scene presentation. The doubled voltage power output of balanced mode helps when you need more presence and incisiveness of the instruments.

No one cares. Teac was dismissed years ago as garbage. Just crack open the case and you'll see a mess of wiring. Teac became a laughing stock and now they're forgotten. R.I.P.

 

[r0ss1992]

No one cares. Teac was dismissed years ago as garbage. Just crack open the case and you'll see a mess of wiring. Teac became a laughing stock and now they're forgotten. R.I.P.

Forgotten by who? they're continuing the reference line 50x, adding new dac, integrated amp and final amp. Ah, they've just introduced a new pre-phono, and have in stock one of few 10mhz master clocks on the market, that is used with Esoteric line products too.
Good listening, again!
Ciao! Ops, i'm sorry...bye!

 

[beautiophile]

Forgotten by who? they're continuing the reference line 50x, adding new dac, integrated amp and final amp. Ah, they've just introduced a new pre-phono, and have in stock one of few 10mhz master clocks on the market, that is used with esoteric line products too.
Good listening, again!
Ciao! Ops, i'm sorry...bye!

I too wonder why Teac is trash. By using their products, I see that they know what they are doing and they have expertise & seriousness on engineering, unlike some headfi sponsors who just put expensive parts together without considering synergy and throw a massive budget on marketing.

 

[endless402]

Teac does amazing stuff for the price point. Build quality is excellent.

Don’t forget that they own esoteric...

 

[r0ss1992]

I too wonder why Teac is trash. By using their products, I see that they know what they are doing and they have expertise & seriousness on engineering, unlike some headfi sponsors who just put expensive parts together without considering synergy and throw a massive budget on marketing.

Teac does amazing stuff for the price point. Build quality is excellent.

Don’t forget that they own esoteric...

I am intent on taking the Teac master clock, maybe on the used market considering its high price.
Anyway I'm completely agree with you and I cannot understand why a great know how company like Teac, is supplanting by some new Chinese companies which do nothing but substantially copy others' engineering concepts, assembling them in a case. Then they sell everything for half the price of the competition, because they manufacturing cost advantage above the rest the world.
But hey, we put lasts Asai Kasei or ESS chips in there, it will sound good in any case Numbers... music playback is not only a question of numbers. IMHO.
Cheers.

 

[r0ss1992]

No experience with planars unfortunately, only my HD 650. Using regular unbalanced connection and I'm not getting anywhere near max volume. I've emailed TEAC Japan about power output and here's the numbers they gave me:

Headphone output (One headphone used)
32 ohm (MAX): Unbalanced 632mW
300 ohm (MAX): Unbalanced 116mW
600 ohm (MAX): Unbalanced 60mW

These values represent peak power, not continuous.

I've emailed TEAC Japan too, questioning output power datas in balanced mode, but no answer yet after almost one moth. I've done the same trying to contact them through the Italian assistance and reseller, that should have a direct contact, since they sell directly their products in my country but no answer as well for now, after a week. Maybe bacause Covid, who knows...
Anyway they say that at 32 ohm the output power is 750mw, continuos. I believe that in any case we should consider peak power as max target, since the analog music signal is alternate current, not a constant line of watt/AV output. I'm not an engineer but I studied elecronical fundamentals in high school and I remember a sort of that
I wold like to listen to your opinion about that and the fact that TEAC is not a reference amp, clear, but in the market there's a kind of run to put very high specifications datas on some lists and it's like buyers chose products upon them and only them.
Sorry for my bad bad English, again

 

[Josef Parran]

I always contacted TEAC through the contact form on their Japanese website. It was a bit tedious translating Japanese but it's doable. Always received prompt response, usually in a couple of days. I kept my queries short and to the point.

The online spec states Max Output Power. In most cases this will be max peak power so that the manufacturer can specify the highest possible figure. As you know, continuous and peak power are two very different things. This is the assumption I would always make. Unless you see continuous, assume instantaneous or peak.

The above numbers were provided to me after some additional in-house measurements. At the time they were only able to test in unbalanced but said these figures should be compliant with balanced operation. In other words, equal or greater in balanced. How much greater is hard to know without actual proper balanced measurements.

 

[r0ss1992]

I always contacted TEAC through the contact form on their Japanese website. It was a bit tedious translating Japanese but it's doable. Always received prompt response, usually in a couple of days. I kept my queries short and to the point.

The online spec states Max Output Power. In most cases this will be max peak power so that the manufacturer can specify the highest possible figure. As you know, continuous and peak power are two very different things. This is the assumption I would always make. Unless you see continuous, assume instantaneous or peak.

The above numbers were provided to me after some additional in-house measurements. At the time they were only able to test in unbalanced but said these figures should be compliant with balanced operation. In other words, equal or greater in balanced. How much greater is hard to know without actual proper balanced measurements.

Teac answers me that max voltage output of headphone amp is the same of the line output both in balanced and unbalanced. So +-6volts in unbalanced and +-12volts in balanced. This because the amplification circuit is one and only one and it's used by RCA/XLR and SE/Balanced headphone output.

 

[r0ss1992]

No one cares. Teac was dismissed years ago as garbage. Just crack open the case and you'll see a mess of wiring. Teac became a laughing stock and now they're forgotten. R.I.P.

https://teac.jp/int/product/ud-701n/top

Teac has just revealed its last DAC, with an embedded proprietary delta-sigma converter, in full discrete components. Forgotten by who????

 

[mrisney]

Build quality is good, I have the
TEAC NT-505-X streaming DAC,
TEAC AP-505 amplifier class D,
B&O H9i headphones
Ophidian Minimo 2 compact speakers. Can't complain