[SOLD] Berkeley Alpha Reference DAC

[MadFloyd]

But isn't class B harsh sounding? The Magicos are so revealing that I would think anything other than Class A would sound a little transistor-like (at least based on prior experience with other brands).

 

[BlueFox]

But isn't class B harsh sounding? The Magicos are so revealing that I would think anything other than Class A would sound a little transistor-like (at least based on prior experience with other brands).

First, I doubt if you will ever get out of Class A with X600.8. The only time I ever get of Class A with the X600.5 is when it is at insane levels, and I no longer listen that loud. However, the X600.5 do take 24-48 hours to sound their best. I posted last week or so that after leaving my amps on from Thursday night to Saturday I felt as if I was back at Magico listening the S7s powered by the Soulution 701 amps.

 

[bonzo75]

But isn't class B harsh sounding? The Magicos are so revealing that I would think anything other than Class A would sound a little transistor-like (at least based on prior experience with other brands).

Not necessarily. For panels, which are tough to drive due to impedance swings, the extra current and slam of Class AB wins over class A

 

[MadFloyd]

First, I doubt if you will ever get out of Class A with X600.8. The only time I ever get of Class A with the X600.5 is when it is at insane levels, and I no longer listen that loud. However, the X600.5 do take 24-48 hours to sound their best. I posted last week or so that after leaving my amps on from Thursday night to Saturday I felt as if I was back at Magico listening the S7s powered by the Soulution 701 amps.

Well the amps must sound different enough or everyone would buy the X series over the XA (the latter are more expensive).

 

[Bruce B]

DIfficult impedance swings is precisely why Logan and such people prefer AB instead of Class A, with Passlabs, or with Lamm M2.2 as opposed to M1.2

Here's what is on the Magnepan website:

Some individuals assume we won't make product or amplifier recommendations for "political" reasons. Not true. We CAN'T make specific recommendations because WE DON'T KNOW. It is too much work to keep up with changing models and the vast number of products. As it is, our small staff is not getting all of our work done. However, the following guidelines will be helpful. Class A/B amplifier designs that come close to doubling power at 4 ohms have a long and successful track record.

A new type of amplifier (Class D) has become more popular because it is a "green" design and uses less power plus it is smaller in size compared to conventional amplifier designs. We have heard reports of Class D amplifiers shutting down when driving 4 ohm loads or sound quality that is less-than-desirable. Quite frankly, some sound very poor on Maggies. However, more recent designs of high-end models are much better. Because we do not have the time to determine which models of Class D designs are compatible with Maggies, we must take a conservative approach. Direct-coupled, Class A/B designs with high current capability have proven a good choice for many decades.

 

[KeithR]

Well the amps must sound different enough or everyone would buy the X series over the XA (the latter are more expensive).

I think this is the wrong question- the right question is what amp is proper to drive your chosen speaker as that will likely sound best. Yes, Class A and A/B can sound different all things equal- but this usually isn't the case. I also bet the output impedance is different between X and XA.

In fact, I can run either since I have very high efficiency speakers- and I'm running Class A/B (Dart). Go figure!

Do you find the M Pros more difficult to drive than your S5s?

 

[MadFloyd]

Do you find the M Pros more difficult to drive than your S5s?

How does one really tell without being able to compare different amps? I get much more tighter bass on the M-Pros with my XA160.8's than I do on the S5's, but the S5's have more bass (and certainly more punch) than the M-Pros. I don't think this is an issue with the amp & speaker match; I think the M-Pros are just more neutral in the midbass region.

If I use my dart NHB-108b to drive my M-Pros I get tons of bass but it's nowhere as tight (and dark sounding) - certainly makes me wonder if it's not driving it that well (which wouldn't surprise me as the dart isn't known for driving low impedance loads).

 

[KeithR]

How does one really tell without being able to compare different amps? I get much more tighter bass on the M-Pros with my XA160.8's than I do on the S5's, but the S5's have more bass (and certainly more punch) than the M-Pros. I don't think this is an issue with the amp & speaker match; I think the M-Pros are just more neutral in the midbass region.

If I use my dart NHB-108b to drive my M-Pros I get tons of bass but it's nowhere as tight (and dark sounding) - certainly makes me wonder if it's not driving it that well (which wouldn't surprise me as the dart isn't known for driving low impedance loads).

since you had both speakers on the same amp, would seem fairly easy. do you have to crank up one a lot higher for large scale classical with big dynamic peaks? are you hearing any strain or distortion at high volume levels (try wide band pink noise at 95dbs), which one feels more effortlessly driven or has more headroom? which is more dynamic? did/does your pass amp ever go right of 12:00? etc.

definitely sounds like the Dart isn't a good match- not unexpected with its unique design. i assume you are using the "Lo" setting, but even then its output is more limited.

 

[bonzo75]

Hi Keith, what is the wide band pink noise test at 95dbs?

 

[KeithR]

sorry i missed this Bonzo- i just found that cranking up pink noise made SS distortion pretty easy to hear. i had the First Watt SIT-2 at the time and it would distort over 93dbs (on my 101db speakers in a somewhat large room)

 

[bonzo75]

What about a more powerful amp? (I know that 25w is normally enough for 101db, but you have a large room, so was wondering if it's that it is an SS, or is it because it is underpowered for a large room)

 

[wisnon]

Here's what is on the Magnepan website:

Some individuals assume we won't make product or amplifier recommendations for "political" reasons. Not true. We CAN'T make specific recommendations because WE DON'T KNOW. It is too much work to keep up with changing models and the vast number of products. As it is, our small staff is not getting all of our work done. However, the following guidelines will be helpful. Class A/B amplifier designs that come close to doubling power at 4 ohms have a long and successful track record.

A new type of amplifier (Class D) has become more popular because it is a "green" design and uses less power plus it is smaller in size compared to conventional amplifier designs. We have heard reports of Class D amplifiers shutting down when driving 4 ohm loads or sound quality that is less-than-desirable. Quite frankly, some sound very poor on Maggies. However, more recent designs of high-end models are much better. Because we do not have the time to determine which models of Class D designs are compatible with Maggies, we must take a conservative approach. Direct-coupled, Class A/B designs with high current capability have proven a good choice for many decades.

A pair of these will tame anything:

http://rowen.ch/en/data/rowen_one.php

4K watts into 0.5 ohms….just what the savage beast demands. LoL

Did you get the package today?

 

[Bruce B]

Did you get the package today?

Not yet.... still waiting for DHL

 

[KeithR]

What about a more powerful amp? (I know that 25w is normally enough for 101db, but you have a large room, so was wondering if it's that it is an SS, or is it because it is underpowered for a large room)

Good questions- and unfortunately I don't really have great answers for you. The SIT-2 is only 10 watts fyi and my room at the time was 25x24x9 (although half the room was dining area). I used Quad iis after that experiment, which are 15 watt push/pull, and didn't have any issues.

I had a Shindo HB amp that was a bit dynamically constricted too (20 watts)- but it was really wound for 8ohm impedance vs. my 6ohm speakers. so the transformer makes quite a difference as well.

 

[wisnon]

Not yet.... still waiting for DHL

Still not there yet?

 

[Bruce B]

Still not there yet?

Today man... today. I missed DHL yesterday. Saw the tag on the door when I came home. Damn I was bummed..

 

[MadFloyd]

Today man... today. I missed DHL yesterday. Saw the tag on the door when I came home. Damn I was bummed..

I hate when that happens!

 

[astrotoy]

Wow, this thread has really gone off track. So, what stylus cleaner do you use? Larry

 

[MadFloyd]

Goodyear all-seasons.

 

[drabbish]

Has this sold?