Відео

Yes, it is possible. Please reach out to our customer service to discuss this more in detail. 1-800-262-4675 or e-mail us at sales@benchmarkmedia.com

Yes, it is advisable to use the boost setting in a situation like this. Add the 10dB of gain to that XLR input and you're all set.

@@BenchmarkMediaSystems Thank you The +10dB gain helped

You could use the CH1/CH2 SpeakON output on the AHB2 if you are running your AHB2 in stereo. It has four connections; 1+, 1-, 2+, and 2-, where 1- and 2- are the grounded terminals of the amplifier. If you are modifying a REL High Level Interconnect cable, connect yellow to 1+, red to 2+, and black to 2- on the new SpeakON connector that you will be adding to the stock REL cable. Notice that we do not recommend connecting the black wire to 1- because this wiring could cause damage to the REL if the connector was accidentally plugged into the mono output on the back of the AHB2. If you are running your AHB2 in bridged mono, you would still use the CH1/CH2 output on the AHB2 (and not the mono output), but the cable wiring would be different: 1+ to yellow and red, 2- to black. If you are using a pair of subs, both will be wired identically and one would be connected to each AHB2. Never plug custom REL NL4 to NL4 cables into the Mono or CH2 SpeakON outputs of the AHB2. This could cause damage to the REL subwoofer. We would rather see you used the SpeakON connectors for you mains and then use the binding posts for the subs. Also, the SpeakON wiring on the REL sub is not standard wiring, so you cannot use an off-the-shelf NL4 to NL4 cable. Furthermore, your custom wired NL4 to NL4 cable will not work if you reverse the amplifier and sub ends of the cable. Incorrect connections could damage the REL subwoofer. In general, it is probably a bad idea to create a custom NL4 to NL4 cable unless it is very clearly labeled.

Yes, adding spades to the end of the wires would improve the durability of the wires. I'm not sure why REL doesn't supply them with terminals. It would be a nice improvement. As for the shielding of the power cord, this is absolutely not necessary from the standpoint of audio interference. Shielding will prevent the radiation and/or reception of radio-frequency interference but it will not block any interference due to the magnetic fields produced by current flowing through the power cord. Braided and/or foil shields do not block magnetic interference. But even if there is some magnetic coupling between the power cord and the speaker-level inputs on the REL, that interference would be so much lower than the speaker-level signal that is would not produce audible noise at the output of the sub. In contrast, power cords can interfere with the very low-level signals coming from microphones. We recommend star-quad microphone cables because they can produce a 20 to 50 dB reduction in magnetic interference. The is very important at microphone levels, is less important at line levels, and is not important at speaker levels.

I assume you are referring to the so called "IMD hump" that is exhibited by most DACs that use the ESS chips. The Benchmark DAC2 and DAC3 do not have this problem. We were able to correct it externally before ESS corrected it internally.

@@BenchmarkMediaSystems no it’s not that. I sent an email to Rory and John today explaining. Thanks so much for replying tho. Archimago has an article explaining and showing measurements of what it is. He also spoke to the engineers of ESS. It was solved by the new Hyperstream IV. I have the AHB2 , LA4 and DAC3 btw. All are amazing pieces.

We have confirmed that the DAC3 does not have the Sinusoidal distortion problem that is seen in some ESS DACs. We use the ESS chip a bit differently.

@@BenchmarkMediaSystems that is very cool. Thanks guys ! This is why I always buy your stuff.

The optical outputs on the Apollo 8p are ADAT (8-channel) outputs. These outputs do not support S/PDIF (2-channel) digital audio. It is not possible to use the ADAT outputs directly. You would need an ADAT to S/PDIF format converter. If you wish to use sample rates above 48 kHz, the format converter would need to support ADAT SMUX to S/PDIF conversions. The following is from page 22 of the Apollo 8p manual: "Note: The ADAT ports use TOSLINK JIS F05 optical connectors. Some devices use this type of connector for optical S/PDIF connections. However, Apollo 8’s ADAT ports do not support the S/PDIF protocol."

You are correct. Any noise or distortion produced by the main power amplifier will be added to the subwoofer output. However, it will be added at about unity gain (+/- a few dB), it will not be amplified. But, because this noise and distortion will be added to the output of the sub, it is very important to use a main power amplifier that is very clean. Obviously, the AHB2 is the perfect choice for this task because no power amplifier (at any price) has lower noise or lower distortion. This means that the noise and distortion added by the AHB2 will not reach the 0 dB SPL threshold of hearing at the output of the main speaker or at the output of the subs. In contrast, many power amplifiers produce noise that is 20 to 25 dB higher than that of the AHB2. Worse yet, this noise is often dominated by AC mains line related hum. This line related hum is in the passband of the sub, so it could be a problem with many so-called high-end amplifiers. We recommend the high level inputs when driven by the AHB2, but would not recommend using them with most other power amplifiers.

We often team up with Martin Logan at Audiophile Shows. We like the ESLs because they produce much less distortion than conventional drivers. The AHB2 is a perfect match for the the Martin Logans because the AHB2 distortion is so low that the distortion artifacts will never exceed 0 dB SPL when driving speakers, even when driving difficult loads. The Martin Logans have very low distortion, an this makes them very revealing. If you drive them with a poor amplifier, you will hear it. As for the peak output level, you can add 20 dB to the 2.83V sensitivity rating of the speaker when running an AHB2 in stereo mode. When running an AHB2 in mono mode, add 23 dB to the sensitivity rating of the speaker. When you do the math, you will find that the Martin Logans will play very loud from a single AHB2. Here is a link to a calculator on our website that will calculate the peak SPL that you can expect from your speaker/amplifier combination: benchmarkmedia.com/blogs/calculators/simple-spl-calculator

ua-cam.com/video/mjAwcBi2Orw/v-deo.html

Yes! Open the balance screen by pressing the BAL button on the screen. While this screen is displayed, you can use the INPUT <- -> arrow buttons on the remote to adjust the balance. This feature in not available in early versions of the software, but free updates are available.

With a flip of a switch, the AHB2 is that muscle amp. The switch is the stereo mono switch on the back of the amplifier. In bridged mono mode, the amplifier delivers almost 4x the power. 390W into 8 Ohms, and 516W into 4 Ohms. The other unique feature of the AHB2 is that THD does not increase when the amplifier is heavily loaded. This characteristic is due to the patented feed-forward error correction system. We have a set of 2.4 Ohm speakers in one of our listening rooms, and the AHB2 drives them cleanly. Any other amplifier would produce greatly elevated levels of THD. The manufacturer of the speakers selected the AHB2 because it was able to drive these cleanly. They have now modified their speakers so that they have a nominal impedance of 4 Ohms. At 4 Ohms, they can be driven by a variety of amplifiers.

Yeah... It's about time to come out with stereo 200 watt amp. Most people prefer not to bridge.

That media rack was put together by one of our former employees who was doing carpentry as a hobby.

He did a great job. Well done.

The gain of the bypass function on the LA4 is fully programable. Each input is individually programable. For example, input 3 could be set to a fixed gain of 3 dB while the other three inputs are controlled by the volume control. It is also possible to have 2, 3 or 4 inputs programmed to fixed gains, and these gains can all be different.

@@BenchmarkMediaSystems thanks this is very helpful. So with LA4 could set the xlr input coming from my processor as unity gain and if needed adjust the gain to better match to the sensitivity of the AHB2. Is that correct?

@@kyleo2113 Yes, each input can individually be set to any fixed volume setting desired.

Place the switch on the rear panel in mono. Use "1 In/Mono In" for the input. If you're using the Binding Posts then you will use the two red middle binding posts marked "M+ Out and M - Out". If you're using a SpeakOn connector then use the SpeakOn plug marked "Mono Out".

@@BenchmarkMediaSystems hpa4 volume is too low, is there any way I can get more gain? when i use other pre amp for my system the volume is fine. i think the hpa4 is doing automaticaly something to protect thw circuit. when I increase input volume noise rises too. I will be selling this hpa4 if there is no way to increase gain without noise.

​@@noob9103​ Please send us an e-mail and we can have our tech support help you with this. sales@benchmarkmedia.com

The HPA4 and LA4 have more gain available than most preamplifiers. 0 dB on the volume control is unity gain (XLR to XLR or RCA to RCA). The maximum gain is +15 dB. The volume control goes all the way down to -112 dB in 0.5 dB steps. When the volume control says -50 dB this is not 50% it is -50 dB relative to the input signal which is a very low level. The analog circuitry in the LA4 and HPA4 are very low noise and these devices will not produce audible noise. If you are hearing noise when turning the volume control up to +15 dB, this is due to the noise coming from the source device.

The competition does not have the high-headroom DSP processing. This headroom prevents DSP overloads when audio peaks exceed 0 dBFS. These high-level peaks can occur many times per second, even on well-recorded tracks.

On your HPA4 or LA4 you will need to enable "BENCHMARK DAC ON XLR1". You will find this under Settings/Remote.

@@BenchmarkMediaSystems I did, all the settings are locked as they are in this video - the only thing that doesnt change is my screen - instead of "DAC" it still reads "XLR-1". No biggie.

It will say DAC if you use the touch screen or the input scroll buttons on the remote. But, if you select the input using the Benchmark remote, the screen will display the input selected (USB, D1, D2, D4, or D4). For example, press the USB button on the remote and the DAC will switch to the USB input and the HPA4/LA4 will display USB on the screen (while switching to the XLR1 input). By the way, you can rename these inputs.

I believe that’s the DAC3 HGC.

Send me 2800$.

Probably because this video is several years old. He is actually using a DAC1, which is well over a decade old. I wonder why they didn't just do a proper new video.

This video is over 10 years old. It was a quick post that ended up being very popular.