AMB Laboratories DIY Audio Forums

A balanced Beta22 at 50W/pm would not make a good preamp. It would not even work in class A at those power levels. A balanced Beta22 designed to work as a preamp connected to a class A Beta24 would be a beastly setup in IMHO. Nebby Posts: 316 Likes: 0 Posts: 0 Posts Connected: April 23, 2010 at 4:08 Location: Maryland Maryland

DorkVader " August 9, 2010, 2:02 pm

Re: ОІ24 in pure class A

Oh, and I don't think I've ever driven any speaker I've ever used at more than 15W, let alone 30W.

I hope people start collecting soon.

DorkVader Posts: 493 Likes: 0 Posts: 0 Member Created: April 7, 2010 at 8:21 am Location: Boston Country

Nebby " August 9, 2010, 3:28 pm

Re: ОІ24 in pure class A

IMHO, the Beta22 at 50 watts per minute per speaker is closer to a "standard amp configuration". At the very least, the heatsinking required between the amp and the power board would be substantial. I'd considered it before, but decided it wasn't worth it. Luckily, the amb beta24 was developed to fill that gap! Nebby Posts: 316 Likes: 0 Posts: 0 Posts Connected: April 23, 2010 at 4:08 Location: Maryland Marylandland

By barnaclebeau " August 9, 2010, 7:52 PM

DorkVader " August 9, 2010, 2:02 pm

Re: ОІ24 in pure class A

barnaclebeau Posts: 37 Likes: 0 Posts Likes: 0 Posts Connected: April 7, 2010 at 7:22 AM Country:

by amb " August 9, 2010, 8:23 pm

Nebby wrote: The balanced beta22 is designed for 50Wrms output so it's not suitable for a preamp. A balanced Beta22 designed to act as a preamp connected to a Class A Beta24 would be a beast of a setup in IMHO.

Re: ОІ24 in pure class A

The balanced Beta22 can deliver 50W into 8О©, but it operates in Class AB and you can't expect to do so all the time without overheating the output MOSFETs, no matter how big the heatsink. You get to the point where the thermal resistance of the TO-220 MOSFET package becomes a bottleneck.

If you use a balanced ОІ22 as a preamplifier of ОІ24 (pure A or AB class), it will be a fun (and expensive) configuration. If ОІ22 is used as a preamplifier, it will not be obtained because it will drive the highest loading load (regarded as ОІ24 input Z). In fact, the output power of the ОІ22 of this role is ridiculous because there is no waste. The steady ОІ22 can be driven to clipping within 30vrms, but ОІ24 requires 2VRMS or less to give absolute output power with 8О©, so ОІ22 does not approach clipping. If ОІ22 supplies 2VRM to the Z in the 5K ohm of ОІ24, it will be supplied 0 and 8MW. Yes, it's just a milliwatts.

Let's continue the first task of JTOSTENR:

JTOSTENR wrote: What are the benefits of adding B24 (pure A-class variant) to the signal chain?

Well, it will be a class A that is untouched until the absolute output. In addition, large MOSFET and huge radiator allows the amplifier to supply high power over a long period of time without being damaged.

In fact, I think it is possible to drive B24 class A with B22 as low gain, but if B22 supplies 50W/ month with standard gain, why do you need to add B24?

Gain has nothing to do with the maximum output. Even if the total gain of the preamplifier and power amplifier can output a considerable bolt with only the switch, you can supply several hundred watts with an 8О© load. Of course, it's not easy to find a key that outputs 30vrms+, but you can see it.

The conventional gain of the preamplifier is from 5 to 10 (secure the required volume adjustment range for a wide range of sources and average recording values). The simple power amplifier gain is the selection of the manufacturer (how much is the absolute output power of the amplifier, which actually leads to the value of the output voltage swing, and what is the input voltage required to achieve this)? The range is 1 to 30). In the case of pure A-class ОІ24, the gain is smaller than 15, for example, if it is 1VRMS or more, the output will be perfect.

Navy "August 9, 2010 20:53

The balance BETA22 designed for the power of NEBBY WROTE: 50WRMS is not a preferred preamplifier. If you combine the balanced ОІ22 designed to work as a preamplifier and the class A ОІ24, IMHO will definitely be a terrible device.

Re: ОІ24 in pure class A

The balanced ОІ22 can output 50W with 8О©, but it works in the AB class, and it cannot be expected that MOSFET is constantly operated without heating, regardless of the radiator size. The fact that the thermal resistance of the body of the MOP transistor of TO-220 is narrow.

If you use a balanced ОІ22 as a preamplifier of ОІ24 (pure A or AB class), it will be a fun (and expensive) configuration. If ОІ22 is used as a preamplifier, it will not be obtained because it will drive the highest loading load (regarded as ОІ24 input Z). In fact, the output power of the ОІ22 of this role is ridiculous because there is no waste. The steady ОІ22 can be driven to clipping within 30vrms, but ОІ24 requires 2VRMS or less to give absolute output power with 8О©, so ОІ22 does not approach clipping. If ОІ22 supplies 2VRM to the Z in the 5K ohm of ОІ24, it will be supplied 0 and 8MW. Yes, it's just a milliwatts.

Let's continue the first task of JTOSTENR:

NEBBY Posted: 316 Like: 0 Post IF: 0 Post Act: 23 APRIL 2010, 4:08 AM Location: Breaked ОІ22 with a balanced ОІ22 can output 50W, but it operates in the AB class. Regardless of the size of the radiator, it cannot be expected to operate the mosfet constantly without heating. The fact that the thermal resistance of the body of the MOP transistor of TO-220 is narrow.

Regarding the balance ОІ22 as a preamplifier of ОІ24 (pure A or AB class), it will be a wonderful (and expensive) combination. When using ОІ22 as a preamplifier, there is no 50 watts because it operates with a high load (this is ОІ24 in input Z Z). In fact, with this role ОІ22, the output power is poor and it is meaningless. The balanced ОІ22 swings up to about 30 cuts with RM, but ОІ24 requires 2 or less in RM to output 8О©, so this is good, not the ОІ22 approaches the cut. When ОІ22 is input to Z ОІ24 5О©, voltage 2V is supplied.

DorkVader " August 9, 2010, 2:02 pm