[DarkAngel]

Quote:

Originally Posted by Kees /img/forum/go_quote.gif The tubes in the v8 are slightly easier to change than the v3. (you don't have to unscrew the whole back panel, just the screw that fastenes the RCA terminals).

Never owned the v3.......thanks for the tip about only removing the RCA screw on back, before I was removing entire back panel.

Still a hassle to change out tubes with v8 compared to most other tube headphone amps that have exposed tubes..........

 

[argentum]

Gradofan2 is X - can V8 the best all around amp that you own/have owned or is some unit of your current/previous ones superior ?

 

[Gradofan2]

Quote:

Originally Posted by argentum /img/forum/go_quote.gif Gradofan2 is X - can V8 the best all around amp that you own/have owned or is some unit of your current/previous ones superior ?

Only with low impedance phones (e.g. D5000s, Grados, ATHs, etc.). The X-CANv3 was also pretty good with low impedance phones, and was better with high impedance phones than the v8.

The v8 is OK with Senns and high impedance phones, but its a bit underpowered (voltage) with Senns - I have to set the POT to 2-3 O'clock (about 70% of max) to obtain good volume with Senns (I've discussed this extensively in other posts re: the v8).

In my limited experience, the DV332 is the best amp with Senns in the <$700 price range - and I suspect the DV337 is the only better amp with Senns in the <$1000 price range. The DV337, reportedly, also drives both high and low impedance phones really well.

If I were going to buy an amp (in the <$1000 price range), that reportedly is great with both high and low impedance phones, it would likely be the DV337 - and, I may still buy one - just haven't yet gotten comfortable with the "risk" related to the high cost of shippng back and forth to China.

My next choice to drive both high and low impedance phones would likely be the SP Extreme, or possibly the WA 6 maxed (close second).

Though, I may give the GS-1 a try - just to see how it does with both - I really don't expect it to do really well with both. It reportedly drives Grados well, and I suspect it would "clear up" the Senns, quite a bit.

However, if I were just going to drive D5000s and other low impedance phones - I'd likely choose the v8, because it sounds great with those, and has adequate power (current) to drive them well. It is a huge value with those phones.

 

[mrarroyo]

^ I am still in shock you are having to go to 2-3 o'clock to get an acceptable level with your Senn cans. I had the V3 and still own the V2 and I rarely go past 9-10 o'clock, and at 10 o'clock I can only stand it for a few minutes.

The V8 according the Musical Fidelity has more power than the V3 or the V2.

 

[Gradofan2]

Quote:

Originally Posted by mrarroyo /img/forum/go_quote.gif ^ I am still in shock you are having to go to 2-3 o'clock to get an acceptable level with your Senn cans. I had the V3 and still own the V2 and I rarely go past 9-10 o'clock, and at 10 o'clock I can only stand it for a few minutes. The V8 according the Musical Fidelity has more power than the V3 or the V2.

That's right - see my posts.

I've had two units, and they both have the same issue with 5 different sources.

My v3 did not have this issue - it had higher impedance - which is the issue with the v8.

 

[jpelg]

Quote:

Originally Posted by Gradofan2 /img/forum/go_quote.gif My v3 did not have this issue - it had higher impedance - which is the issue with the v8.

I assume you are refering to the output impedance at the headphone jack?

What are the respective output impedance specs for the v3 and v8?

How does a jack's output impedance alter the resulting loudness from the headphones?

 

[donunus]

Quote:

Originally Posted by Gradofan2 /img/forum/go_quote.gif That's right - see my posts. I've had two units, and they both have the same issue with 5 different sources. My v3 did not have this issue - it had higher impedance - which is the issue with the v8.

Anyway that was a faulty unit and the new one has plenty of gain right

 

[Gradofan2]

Quote:

Originally Posted by jpelg /img/forum/go_quote.gif I assume you are refering to the output impedance at the headphone jack? What are the respective output impedance specs for the v3 and v8? How does a jack's output impedance alter the resulting loudness from the headphones?

You can look up the specs as well as I can.

The v8's output impedance is 1-2 ohms.

The point is... the output impedance of the v8 matches the low 25 ohm impedance of the D5000s, which makes all the difference in their sound. The amp provides sufficient current to meet the high current requirements of the Denons and Grados, but does not provide sufficient voltage to meet the high voltage requirements of the Senns. Consequently, the amp controls and drives the drivers of the Denons and Grados much more easily than it does the Senns - and therefore, requires lower POT settings for the Denons and Grados, than for the Senns.

 

[Gradofan2]

Quote:

Originally Posted by donunus /img/forum/go_quote.gif Anyway that was a faulty unit and the new one has plenty of gain right

Actually, the replacement unit has a bit more power, but still seems to struggle with the Senns (maybe 2 O'clock, instead of 3 O'clock), and its much quieter (little, or no hiss at full volume with no signal).

But... I still wouldn't recommend it with Senns - though I would with low impedance phones.

I think the reason some don't seem to encounter this issue - is their in 240 volt countries, which must provide improved output voltage with the amp.

 

[jpelg]

Quote:

Originally Posted by Gradofan2 /img/forum/go_quote.gif You can look up the specs as well as I can.

Uhh...thanks. Just thought that since you have used both, and are stating technical reasons for their respective performance differences, you might have this more readily. Sorry to put you out.

Anyway, I did look it up:

v8
Power Output: 1.3 watts into 32ohms
Output Imped: 2 ohms

v3
Power Output: 1 watt (no load spec)
Output Imped: 47 ohms

Even the v3's output impedance is relatively low, and should not be too detrimental, although admittedly not as ultra low as the v8 spec. Still, since both amps are hybrids (tube input, op-amp output), they both should fair decently with low-impedance cans, compared to straight tube amps.

The other question is regarding the low volumes you report using Sennheisers. While I don't dispute that you experienced differences, the comparative v8's specs don't support the reasons you state. In fact, the v8 has a higher rated output power (although no load stated for the v3).

Other users, both here on Head-Fi, as well as the Stereophile reviewer did not note such issues. Since you had similiar experiences with both of your samples, I'm still trying to understand the "why's".

Does anyone know what MF did to tweak the new v8 circuit, compared to the v3? How did they lower the output impedance? Are there differences in the output buffers?

 

[DarkAngel]

I have both Senn 650 and Denon 5000 and Xcan v8 has no problem at all playing these headphones with very little adjustment to volume setting.

Denon 5000 loud at 10 o'clock
Senn 650 loud at 11 o'clock

Seems to play both equally well

 

[Mammut]

My Senn 580 is loud at 10-11 o'clock with the v8

 

[Gradofan2]

You guys must be using 240 volt mains, or a source with exceptionally high output power 3.5+ volts, or your using a line stage to boost the signal, or a PC with additional sound card boost settings... or... I must still have a pretty weak unit. I realize "we've covered this ground" earlier.

Also - you may have indicated previously... but... are you using the X-PSUv8?

Both of my units were much better out of my line stage - but that shouldn't be required.

I can't believe I could get two relatively "lower power" units from two different vendors (Music Direct and Audio Advisor), one of which only recently received their units (more recent production) - although the second is better than the first, its still very, very low volume at 10-11 O'clock with Senns.

Maybe... I'll try "one more time."

 

[DarkAngel]

Quote:

Originally Posted by DarkAngel /img/forum/go_quote.gif I have both Senn 650 and Denon 5000 and Xcan v8 has no problem at all playing these headphones with very little adjustment to volume setting. Denon 5000 loud at 10 o'clock Senn 650 loud at 11 o'clock Seems to play both equally well

My CD player has normal output level at 2V, USA power
The X-PSU v8 power supply does not effect volume level, just sound quality.

GF2
you should try connecting your X-Can v8 directly to CD player with no other processors or EQ devices, and make sure front toggle switch is in "line" position........should have plenty of power

 

[Gradofan2]

Quote:

Originally Posted by DarkAngel /img/forum/go_quote.gif My CD player has normal output level at 2V, USA power The X-PSU v8 power supply does not effect volume level, just sound quality. GF2 you should try connecting your X-Can v8 directly to CD player with no other processors or EQ devices, and make sure front toggle switch is in "line" position........should have plenty of power

"I've been there... done that" - makes no difference.

I'm amazed that 2V output is loud at 10-11 O'clock with the Senns.

The only difference between my set up and yours is the X-PSUv8... I wonder...