[DocHamm]

  I just dusted off my A1 for speaker use.. and I tried out the RCA output for the first time..and it works as rca in not out..  this makes me sad

 
I was under the impression that, as an integrated amplifier, the RCA was input or tube pre-out only. Has this changed?
 
Per Maverick Site ... "~~A1 is also a tube pre-amplifier, therefore, you can connect your Amplifier or even connecting a Sub-woofer to the A1 via the tube pre-output."

 

[uncola]

It has RCA in and RCA out.. the rca out is labled tube preamp..  doesn't that just mean it's rca output?  or does tube preout mean something I don't know about?  I was using the rca out to connect a subpac

 

[Soundsgoodtome]

Hi,
Do you know if it will drive the HE-4 correctly, I'm thinking about getting those cans.
Thanks !

Does anyone know if you can drive the HE4 or similar low efficiency ortho through the speaker out on the back of the A1?

Label shows 4-16Ohms but the headphones are 32-38ohms.

 

[Curlycat]

 
Does anyone know if you can drive the HE4 or similar low efficiency ortho through the speaker out on the back of the A1?

Label shows 4-16Ohms but the headphones are 32-38ohms.

 
 
^^^^^ Bump... .... anyone?
I also would like to know the answer to this one?

 

[Soundsgoodtome]

You can but it doesn't sound good. Overly bright and sibilant. Might be a better match for a dark ortho like LCDs.

 

[_Spanky_]

Do not drive headphones from the speaker output, you risk frying them. The speaker and headphone output is the same so there's no reason not to use the headphone output on the front. 

 

[shiorisekine]

It upsets me that this amp isn't talked about that much and it makes me hesitant to buy it. Does this amp not sound good?

 

[Soundsgoodtome]

It upsets me that this amp isn't talked about that much and it makes me hesitant to buy it. Does this amp not sound good?

It sounds good to me.

Although the HP out sounds better with certain low impedance cans than others.


 

  Do not drive headphones from the speaker output, you risk frying them. The speaker and headphone output is the same so there's no reason not to use the headphone output on the front. 

The speaker and HP out are not the same. The speaker output is a hybrid while the HP out is all tube out.

 

[_Spanky_]

 

The speaker and HP out are not the same. The speaker output is a hybrid while the HP out is all tube out.

Unless the circuit board design has changed since I owned one, they are the same output. I followed the traces on my unit before modifying it for different functionality (see Spanky's Mod in the first post). The only difference between the headphone and speaker output is that the headphone output has a resistor circuit to lower volume.

 

[Soundsgoodtome]

  Unless the circuit board design has changed since I owned one, they are the same output. I followed the traces on my unit before modifying it for different functionality (see Spanky's Mod in the first post). The only difference between the headphone and speaker output is that the headphone output has a resistor circuit to lower volume.

Then what's this all about under the FAQ?

 

  TubeMagic A1 Hybrid Amp
Maverick Audio Website - Product Page
  FAQ's

Spoiler

1. 20 watts (30 peak) per channel of output power. [Ryan: "The maximum output of the A1 will be about 30 watt, however, we want to be a bit conservative about the power rating. In theory, it should have no problem to offer 30 watt / channel power, however in real world use, with different speakers, it may not be able to reach 30 watt in some cases. Therefore, we rated it as 20 watt to ensure we are not misleading any customer."]
2. Uses a 80-Watt R-Core transformer.
3. Uses 2 6AK5 / 6J1 tubes.
4. Has National Semiconductor LM1876T used with the tubes to power speaker outputs.
5. Headphone amp is driven purely by tube. Power amp is a tube / solid-state hybrid.
6. Output power cannot be modified to push more watts.
7. Same case and style as the TubeMagic D1 DAC/Amp
8. Accessories included: Manual, 1/8" to 1/8" cable, 1/8" to 1/4" adapter, power cable. RCA interconnect is not included due to Ryan not wanting to give customers a cheap cable with the A1.
9. Initial pricing will be $199 for the stock Chinese 6J1 tube and $239 for 2 matched NOS Tung-Sol 6AK5 tubes.
10. First 30 pre-orders will be shipped on the 10th of August.
11. Wire up to 9AWG in size will fit in the speaker posts in the back of the unit. Both spades and banana plugs can be used as well.

 

[_Spanky_]

 

Then what's this all about under the FAQ?

 

  TubeMagic A1 Hybrid Amp
Maverick Audio Website - Product Page
  FAQ's

Spoiler

1. 20 watts (30 peak) per channel of output power. [Ryan: "The maximum output of the A1 will be about 30 watt, however, we want to be a bit conservative about the power rating. In theory, it should have no problem to offer 30 watt / channel power, however in real world use, with different speakers, it may not be able to reach 30 watt in some cases. Therefore, we rated it as 20 watt to ensure we are not misleading any customer."]
2. Uses a 80-Watt R-Core transformer.
3. Uses 2 6AK5 / 6J1 tubes.
4. Has National Semiconductor LM1876T used with the tubes to power speaker outputs.
5. Headphone amp is driven purely by tube. Power amp is a tube / solid-state hybrid.
6. Output power cannot be modified to push more watts.
7. Same case and style as the TubeMagic D1 DAC/Amp
8. Accessories included: Manual, 1/8" to 1/8" cable, 1/8" to 1/4" adapter, power cable. RCA interconnect is not included due to Ryan not wanting to give customers a cheap cable with the A1.
9. Initial pricing will be $199 for the stock Chinese 6J1 tube and $239 for 2 matched NOS Tung-Sol 6AK5 tubes.
10. First 30 pre-orders will be shipped on the 10th of August.
11. Wire up to 9AWG in size will fit in the speaker posts in the back of the unit. Both spades and banana plugs can be used as well.

Touche. I actually wrote up a whole thing about not having proof and possibly being wrong but I just found a picture I made ages ago that shows the paths and actually shows that the speaker and headphone outputs are soldered to the same hole on the PCB:
https://dl.dropboxusercontent.com/u/464376/website/audio/mav_a1/DSC07369_mod.jpg
 
Take a look at the red & black wires coming from the speaker ports, they come in and are soldered near the center of the picture, if you look more, other wires are bunched with it, these are the headphone output.
 
I'm betting that the info in the FAQ, some of it anyway, was provided by Ryan of Maverick Audio and was put there before I made modifications to my unit and, well, I forgot to update it.

 

[_Spanky_]

Just updated the FAQ for you. Thinking a little more into how the unit functions, the output coming from the tubes is what the volume controls. The solid-state chip amps the output at a constant volume which is probably why there's been reported hissing in headphones. So, even if you have the volume turned down all the way, the solid-state chip is still amplifying an empty signal at full volume. Hisssssssssssssss.

 

[Soundsgoodtome]

  Just updated the FAQ for you. Thinking a little more into how the unit functions, the output coming from the tubes is what the volume controls. The solid-state chip amps the output at a constant volume which is probably why there's been reported hissing in headphones. So, even if you have the volume turned down all the way, the solid-state chip is still amplifying an empty signal at full volume. Hisssssssssssssss.

Gotcha. It sure does run to the same spot. I guess the other question would be Is there a way to remove resistors to get more power out of the HP out? Or does it not work that way? (I'm not technical in amps btw but know someone that can mod this if possible)

 

[_Spanky_]

 
Gotcha. It sure does run to the same spot. I guess the other question would be Is there a way to remove resistors to get more power out of the HP out? Or does it not work that way? (I'm not technical in amps btw but know someone that can mod this if possible)

It's definitely possible. There's a resistor on either side of the headphone jack. From the pics I have, I think the resistors are 240 ohm 5% tolerance. I would imagine upgrading these to a higher quality would also help sound out. You could perhaps contact Ryan to see what he or his engineer think about a 10 or 20% reduction of resistance for louder volumes.
 
Take a look at these pictures, you can see the resistors on either side of the headphone jack, where the red & black wires go to:
https://dl.dropboxusercontent.com/u/464376/head-fi/mav_a1_condensed/DSC08812.JPG
https://dl.dropboxusercontent.com/u/464376/head-fi/mav_a1_condensed/DSC08813.JPG
https://dl.dropboxusercontent.com/u/464376/head-fi/mav_a1_condensed/DSC08815.JPG

 

[Soundsgoodtome]

Update to below: hp out left channel is also bad. Going to inspect and re-seat or replace tubes.

Question guys, I've sold my A1 to another member and when he plugs his speakers in the left channel is low in volume and has bad frequency response. However the headphone out seems to be working fine on both sides, he's going to double check.. If the headphone works on both channels proper, we can rule out a tube correct?

Both speakers work, verified by switching leads (but problematic channel switches sides). Could it be a bad speaker wire/terminations?