Running EAR 890s as mono blocks

[Chops]

Does anyone have experience of two EAR 890's as mono blocks. (They can be bridged.)

I currently have just one of these (non-bridged) driving PMC PB1i's, which PMC state are 6ohm impedence, 87dB sensitivity and benefit from power amps in the range 90-350W.

Very pleased with how things sound at present, certainly don't sound lacking in any way, however I gather PMCs benefit from plenty of grunt. More transparency with a little more tightness in the bass is what I'm looking for.

Review here http://www.positive-feedback.com/Issue27/ear_890.htm likes the idea.

Thanks...Chris

[dgolh]

There are probably some techies who can explain it better than I can, but I think that bridging an amp will double at least its power (the result can be over the double) but it is not the only consequence: wear will be higher, it will get hot and hotter.

I used to have a 890 at home, it should be able to drive your PMCs (I had the smaller OB1) without any problem.

If you want more power, you should look for a pair of 509 instead.

[Chops]

There are probably some techies who can explain it better than I can, but I think that bridging an amp will double at least its power (the result can be over the double) but it is not the only consequence: wear will be higher, it will get hot and hotter.

I used to have a 890 at home, it should be able to drive your PMCs (I had the smaller OB1) without any problem.

If you want more power, you should look for a pair of 509 instead.

Thanks Didier. My understanding is that you flick one of the toggle switches on the back and the left and right channel produce identical output from just one input. You then use a single run of wire to bridge them to run in parallel. I wouldn't have thought this should run any hotter (?).

509s are an option and maybe cheaper than 890s secondhand. Both hard to find. I do prefer the look of the 890s. Any idea of any difference between 2*890 vs 509?

Thanks...Chris

[petrat]

Presumably you are running the speakers on the amp's 4 ohm taps? If not, give that a go.

[Chops]

Presumably you are running the speakers on the amp's 4 ohm taps? If not, give that a go.

I am indeed, thanks Peter.

[The Grand Wazoo]

Vertical bi-amping will make them into mono amps - no messing about with bridging anything.

[Chops]

Vertical bi-amping will make them into mono amps - no messing about with bridging anything.

Thanks Chris. I wondered about this and could do it if I reconfigured my Chord Epic Super Twin speaker cables to run 4-4 rather than the current 2-4. But would it drive the bass as well as 140W?

I guess both biamp and bridged are easy to try.

Chris

[User211]

Can't see what the rest of your kit is in your profile.

What preamp are you using? If it is valve based, a solid state passive or TVC may give firmer bass. I had an EAR868PL and it didn't have the fastest or tightest bass - beat easily in this respect by an Air Tight passive, a Marsh 2000B or even a Cayin valve pre - which is unusually quick for a pre of it's type.

80 Watts of valve power isn't far off the mark... TBH.

[Chops]

What preamp are you using? If it is valve based, a solid state passive or TVC may give firmer bass. I had an EAR868PL and it didn't have the fastest or tightest bass - beat easily in this respect by an Air Tight passive, a Marsh 2000B or even a Cayin valve pre - which is unusually quick for a pre of it's type.

Yes, its an EAR 868PL fed mostly by a Chord QBD76 DAC, sometimes from its own phono stage, all connections single-ended. Many thanks for the interesting comment - I never thought the 868 could be the issue here.

Just to expand on my thought process ... Don't get me wrong, bass is pretty reasonable and deep. However, I assumed that a power amp with a bit more grip on the speakers would help to give more definition/texture and maybe help throughout the higher frequencies. Now I'm not a techy, but I read that various electrical parameters are at play here; power output, damping factor, current delivery etc. So, joining 2*70W in parallel (bridged) should improve these parameters and give the desired result.

But maybe my 868 pre is the bottleneck on bass quality and possibly overall definition (?).

Thanks...Chris

[sq225917]

Even the 509's, which I owned, are a little rolled off and lacking in absolute grip in the bottom end. The 509's certainly have plenty of texture on the bottom end though, but they aren't Krells.

[User211]

In short, you could try two EAR power amps, and I expect the bass control to be better. It probably ain’t gonna be amazing, though.

You could try a cheap passive like the Tisbury and I bet you find you get more speed in the bass. I’d also expect it to be tighter.

You could also do what I did with the EAR868 and get some serious SS power (450 Watts/4 Ohms Parasound A21 in my case). You WILL get bass control that way – bizarrely you may even feel there is so much of it that it doesn’t sound entirely natural. You may not get perceived bass speed in the mid/upper bass. I didn’t. Much better there with the Air Tight passive/A21 and better again with the Air Tight/211 monoblocks I have.

You may also find your findings do not concur with mine as your surrounding kit is different.

In short - have a play!

[Chops]

Many thanks Justin. Good advice and food for thought.

Just noticed your posts on HFWW. Still using the AAA 211s? I love sourdough :thumbsup: but normally buy from my local Sainsbury's. Make a lot of bread in my bread maker though.

Chris

[User211]

Yes Chris. I've tried so many amps with the Duettas and I like the 211s the best. They are not necessarily the best amps for other speakers, though for my ears they are brilliant with AN/Es too.