The Two Channel Advice Thread

It's definitely the impedance that's giving it fits, it can't handle it. I'm sure it's not rated to handle a 2 ohm load either so I can't really hold it against it, but it's crazy to me people would ever recommend this amp for an electrostat. I just wanted to put a warning out there.

The odd behavior from 5-10 kHz actually makes sense to me, amps do a lot of funny non-linear things before actually tapping out.

 

Never buy a Class D amp without knowing the technology behind at and seeing measurements to confirm that it maintains a low output impedance across its bandwidth. These measurements can either be FR into load at various impedances, or FR a simiulated speaker. Stereophile and Soundstage offer simulated speaker measurements. I don't know of anyone else who does.

As a general rule, anything from Hypex, like your NAD M22, is OK. Anything from Anaview is OK. At least current Icepower is OK. I think that Pascal and Drivecore (Harman) are OK but I have not confirmed. My posture towards the rest is total skepticism unless proven otherwise.

 

Powersoft and Lab Gruppen are also safe bets.

 

I have not seen home audio amps from Powersoft or Lab Gruppen, or measurements of their frequency response into different loads. So while they may be OK for full range home use (no argument regarding subwoofers; pro amps are great for that) I would not presume it.

 

True enough. Luckily I bought it used dirt cheap and won't lose much money on it. I had seen elsewhere someone had said his Summit X was great with it. He must be lying to himself or just ignorant.

 

Conrad Johnson and Audio Research are arguably the two most important american tube amp manufacturer. For best value for money if you buy some 10 years old amp and you restore them, you have a very high end sound for very cheap.
the transformers and design are excellent quality

 

Thanks. I bought the CJ combo and I'm super impressed with the Premier 11 power amp. Lovely detailed and spacious sound, which is just what I was after. The preamp has some issues that I'm working on and hopefully I'll get them up and running as a pair soon.

 

well, prepare to be blwon away after a recap
ifs its over 10 years, recap! tube amp need to be recapped every 10 years, sometime even worth it to do it every 5 years.

 

Thanks, in the end I paid a bargain price for the Premier 11 and my mate gave me the PV12 for free as it wasn't working properly. Nice!

5 or 10 years for a recap seems awfully frequent. Is this the generally accepted wisdom as I've not heard this suggested before?

 

I don't think I've ever done a recap before 10 years, and I usually wait longer. That being said, if I don't know definitively that an amp has been recapped, I'll do a recap automatically (at least the electrolytics) if it's >15 years old.

 

Guru tube guy, Thorsten Loesch words on the matter:
"
Any Amplifier (even Solid State, also CDP, DAC etc.) older than 5 Years (used or not) should have the electrolytic capacitors replaced. Some may need service earlier, if running very hot.

Comparing a new or very recent device to one with tired and out of spec electrolytic caps will outrageously favour the younger model. Often the restored older "high end" Device will however end up much better if restored to original or carefully upgraded (careful not to change original circuits etc. but for example better grade cap's may be fitted, but make sure that "better" does not change the fundamental sound of the Amp).

Amplifiers with > 10 Years age and continuous use may benefit from replacing Film Capacitors and any resistors that get hot in use. Depending on condition stranded wires may also need replacing.

Very old Amplifiers (> 20 Years) benefit from a full re-build (Tube sockets, other connectors, all resistors & Cap's etc.) using high grade modern parts. Again, do such a job strictly as "restoration" not as modification, the the same standards or higher in terms of workmanship as the original work.
"

 

Okay, you have a Mjolnir 2 for your headphones that you also use to drive nearfield powered monitors. You use the MJ2 to control the volume of the powered monitors even though they have their own volume control. What volume level do you set the powered monitors to? Maximum? Less than maximum? Are there any issues with the MJ2 if its volume level gets close to maximum?

I have the powered monitor volume set to maximum. I figure that is how discrete amps are setup so why wouldn't I do that with integrated into speaker amps?

 

Hi everyone,

I'm thinking of picking up the Magni 2U/Modi 2U stack for my headphones and wanted to know if it would be a smart idea to pick up some JBL LSR305s to go with that combo and any considerations for that setup and suggestions anyone had for alternatives if there's something better. I also was thinking of getting a sub, but I don't really know if the 305s need one or how the wiring would work with the MM2U setup. I'm still grappling with understanding how the MM2U unit -> powered speakers -> powered sub wiring would work as far as connections.

Let me know your thoughts if you have any expertise in this area. Thank you, I appreciate all the help.

 

If you've got the space on your desk, you could move up to the 308 and skip the sub.

To hook them up, you'll need two of these: https://www.monoprice.com/product?p_id=4777

When you have headphones plugged in to the Magni2U, the preamp outputs will automatically mute so you don't need to turn off the JBL's.

 

Thanks! I've heard the 308s aren't as highly rated quality wise as the 305s. I do have space though, and it does sound quite convenient.

 

How much space have you got to work with in your room?
Are the speakers on a desk or across the room?
What's your total budget?

 

I set powered monitors to just above maximum volume I'm willing to listen. Gives some headroom, cuts down on hiss from the monitors and will save your ears if something goes wrong if they get full input volume. Of course you can run them with maxed volume if you want.

 

Can anyone recommend me a studio sub or two to pair with my Questeds? Has to have a passthrough for my monitors and a variable x-over. I prefer to have have something that keeps the signal analogue to the monitors but the amp in the sub can be class-d.

Budget about €1500 for the pair.

 

My room is quite small, I would say around 120 square feet. That said, I have had a 2.1 setup in my room before and I liked it. As far as space, I have a long Ikea table that I plan on putting them on so they would need to be on the desk.

My budget is anywhere from 200-400 dollars with some flexibility. I'm willing to pay for quality but I would rather spend MORE on the speakers and less on the sub.

Thank you.

Picture of my desk here:

 

Do you really need the extra bass of the sub? It'd be $200 to go from the 305 to the 308, whereas the matching 310 sub is another $400 plus more cabling.

In a small room you'll be getting a lot of bass reinforcement from the walls anyways, so I don think a sub will be necessary. I would sooner spend that money on stands to bring the speakers up to ear level, and maybe two foam diffusers to put behind them.