2 vs 4 amps (bi-wiring)

[olds1959special]

My speakers are JBL L890's and I'm currently trying them with 2 mono block Aiyima A70 mono amps (with LM4562 op-amps). I took out my Kenwood L-05M's because of their age, potential safety issues, space needed, heat generated and electricity used. I want to add two more Aiyima A70 amps to bi-wire. This will increase the power from 80 watts to 160 watts (into 8 ohms) per speaker. I'm in a medium size living room and like to listen fairly loud sometimes. Will this sound better?

 

[Chrispy]

Passive bi-amping, bi wiring uses a single amp. Your tweeter doesn't need the power. Maybe an increase of 3dB on the woofer. Better not particularly all other things equal.

 

[RandomEar]

It will give you a measly +3 dB in SPL at best. Realistically much less, because your tweeter does not consume 50% of your total power output - so +1 dB is a more realistic estimate. It will sound the same.

Honestly, bi-amping is usually a waste of money. Unless you rip out the crossover and go full DSP, there's not much to gain.

If you don't run your current setup into clipping, you don't need more power. If you do, an upgrade should be at least 4x the current power level with 100% available to the woofers. It doesn't make sense to split power 50/50 between tweeter and woofer.

 

[DVDdoug]

Will this sound better?

Possibly... You'll be able to adjust the woofer & midrange/tweeter separately, and it should go slightly louder.

 

[olds1959special]

It will give you a measly +3 dB in SPL at best. Realistically much less, because your tweeter does not consume 50% of your total power output - so +1 dB is a more realistic estimate. It will sound the same.

Honestly, bi-amping is usually a waste of money. Unless you rip out the crossover and go full DSP, there's not much to gain.

If you don't run your current setup into clipping, you don't need more power. If you do, an upgrade should be at least 4x the current power level with 100% available to the woofers. It doesn't make sense to split power 50/50 between tweeter and woofer.

Side question: Since you're saying the woofer needs more power, I still have one pair of Kenwood amps and have space for them. They are 100 watt into 8 ohm amps. I'm thinking I could use the unused RCA outputs of my DAC to hook them up and try them out connected to the woofers. Then I can use the Aiyima amps to power the tweeters and lower the volume as needed (The Kenwoods don't have volume controls.) I also have the additional Aiyima amps and LM4562 op-amps on the way (to match the ones I'm using now - not sure if this degrades the sound over the stock op-amps.) Should I try this? I'm trying to get away from using the ancient amps if possible, but I haven't been able to sell this pair yet!

 

[kemmler3D]

Side question: Since you're saying the woofer needs more power, I still have one pair of Kenwood amps and have space for them. They are 100 watt into 8 ohm amps. I'm thinking I could use the unused RCA outputs of my DAC to hook them up and try them out connected to the woofers. Then I can use the Aiyima amps to power the tweeters and lower the volume as needed (The Kenwoods don't have volume controls.) I also have the additional Aiyima amps and LM4562 op-amps on the way (to match the ones I'm using now - not sure if this degrades the sound over the stock op-amps.) Should I try this? I'm trying to get away from using the ancient amps if possible, but I haven't been able to sell this pair yet!

This will still not get you a lot more output, will be hardly noticeable but definitely more complicated to use. I'm not going to say you "shouldn't" try it, but you shouldn't expect much/any difference once you set the levels properly.

 

[tineared]

If you want more power you need to move up to an amp with truly more power like a Buckeye Hypex NC502MP 350w @ 8 Ohms 2-channel amp for $750.
Be aware that you'll need to pay attention because that amp could potentially toast your speakers if you're not paying attention while drinking

Buckeye Amps

Buckeye Amps utilizes the most advanced audio amplifier technologies available. Authorized seller for Hypex and Purifi Class D amplifiers. Based in the US. Free shipping and worldwide service!

www.buckeyeamp.com

 

[OldHvyMec]

First of all, it is a 4-way speaker, not a 2-way with a single tweeter using one of the amp rails. Two-way speakers usually don't benefit from bi-amping as much as 3 or 4-way speakers do. The one thing you will benefit from is better control of the sub/bass drivers as far as ringing. It really depends on how many components they have between the drivers and the amp in the passive crossover. The more parts there are between the driver and the amp, the less control you have of the driver damping if you have any at all with 2nd, 3rd, and 4th order XOs.

If you remove all the BS between the driver and the amps and add an active XO, you will be surprised at the advantage and the better control you actually have of the sub/bass drivers. You can increase the power to the drivers and also have a LOT better control of overshoot/ringing.

Do it right, and you will really enjoy the change that most people never do. Understand how a crossover and drivers work first, and there is a night and day difference in how a tight sub/bass system can really sound. It is one of the biggest and best learning experiences I have found out about, a tightly controlled, hard-hitting sub/bass system.

I use servo subs from 80Hz < and stereo bass columns from 80-280Hz that are directly coupled to BIG class D amps. They actually imagine a great center bass phantom, which adds a whole different sound stage to the recording if they recorded the bass tracks (not the sub tracks) in stereo.

Do it right, and you will enjoy the tinker fest you have been missing.

Enjoy, ay!

Regards

 

[RandomEar]

Side question: Since you're saying the woofer needs more power, I still have one pair of Kenwood amps and have space for them. They are 100 watt into 8 ohm amps. I'm thinking I could use the unused RCA outputs of my DAC to hook them up and try them out connected to the woofers. Then I can use the Aiyima amps to power the tweeters and lower the volume as needed (The Kenwoods don't have volume controls.)

As pointed out by fellow members, your system will not explode by testing this. With the volume control of the Aiyima, you can do a poor man's EQ in the form of a high shelf upwards of the crossover point. But that also means it will be difficult to set the exact same levels for the two regions if you want to keep the tonal balance of the speaker. Same problem with the Kenwood/Aiyima and Aiyima/Aiyima combo.

My opinion: If you want EQ, don't do it this way. It would be a super limited and comparatively expensive solution. An EQ in your source or any decent pre-amp with tone controls or 10 band EQ will be miles better. Or remove the crossover and go full DSP - that's a lot of work, though.

I also have the additional Aiyima amps and LM4562 op-amps on the way (to match the ones I'm using now - not sure if this degrades the sound over the stock op-amps.) Should I try this? I'm trying to get away from using the ancient amps if possible, but I haven't been able to sell this pair yet!

Op amps rarely make any audible difference at all [1, 2]. If they do, it's either due to excessive distortion or because the amp starts to oscillate. In this case, the LM4562s will most likely perform identical to NE5532s. If you want a different sound, use EQ, room treatment or different speakers. Changing DACs or amps isn't the way to go.

Instead of adding more Aiyima amps for bi-amping with limited gains, I would still suggest to get something truly more powerful (4x++) if you think more power is needed.

 

[olds1959special]

I hooked up my Kenwoods to the woofers. I also use four subs (12” and 10” each side) crossed over at 50Hz, connected through a multi output device which plays everything together. I used SoundSource subtractive PEQ and low shelf EQ and did some MMM’s until the response looked/sounded good. I ended up reducing the volume of the Aiyimas a few notches to get a good balance.

 

[MaxwellsEq]

Side question: Since you're saying the woofer needs more power, I still have one pair of Kenwood amps and have space for them. They are 100 watt into 8 ohm amps. I'm thinking I could use the unused RCA outputs of my DAC to hook them up and try them out connected to the woofers. Then I can use the Aiyima amps to power the tweeters and lower the volume as needed (The Kenwoods don't have volume controls.) I also have the additional Aiyima amps and LM4562 op-amps on the way (to match the ones I'm using now - not sure if this degrades the sound over the stock op-amps.) Should I try this? I'm trying to get away from using the ancient amps if possible, but I haven't been able to sell this pair yet!

Bi-amping and bi-wiring with different amplifiers with different gains or input sensitivities is trickier than using the same amplifiers. You will need to make careful measurements to set levels.

And as others have pointed out, unless you remove the crossovers and go active, you will get no real measurable benefit. If you are short of power, buy an amplifier with four times your current wattage to get a measurable benefit.

 

[Ropeburn]

If you want more power you need to move up to an amp with truly more power like a Buckeye Hypex NC502MP 350w @ 8 Ohms 2-channel amp for $750.
Be aware that you'll need to pay attention because that amp could potentially toast your speakers if you're not paying attention while drinking

Buckeye Amps

Buckeye Amps utilizes the most advanced audio amplifier technologies available. Authorized seller for Hypex and Purifi Class D amplifiers. Based in the US. Free shipping and worldwide service!

www.buckeyeamp.com

I'm kinda glad my speakers can apparently handle 2x250W peak for a while, because last new year's party involved exactly that while drinking... they're rated 200/300W RMS/peak, and for once, that doesn't seem a lie. Not bad!

 

[Oddball]

I tired ti-amping my LR albeit with more powerful amps. I did not measure better or produce any audible benefit. Not the same case as OP, but indicative. Once you amp them right, IME no need for additional wires and amps.