'upgrading' DM310 --> 603(/604) or 705 ?

[bebo]

Hello,

Since the early '90's I own B&W DM310 speakers which brought me lots of pleasure; now I'm considering buying new ones.

I've done some research and the choice is between the 603 (or perhaps the 604) and the 705. My wife prefers the 705 (she doesn't like those big ones in the room).

Of course I know I should listen to them and I will, but I would like to know your opinion about the 'upgrading' I'm planning to do. The speakers will perform together with a Denon amplifier (65W 8 ohm/100 W 4 ohm) and most of the time I'm playing classical music.

[BlazeMaster]

Have you considered getting a pair of 805/S? The reason I asked is because the 800s seems to be the best speaker for classical genre. Maybe other owners of 800s series will chime in on this one.

[bebo]

To be honest; I didn't because of the difference in price.

I live in Europe; the 705 costs Euro 1400 (pair); the 805/s Euro 2500 (pair). (603 = Euro 980 pair/604 = Euro 1340/pair)

(1 US dollar = 0,80 Euro / 1 Euro = 1,25 US dollar)

[RebelMan]

The 800 series is best suited for classical and jazz genre's, as BlazeMaster pointed out. In fact, the top end (802 and above) are often used as reference models when monitoring classical recordings.

The 700 series has inherited more of the "Nautilus" characteristics than the 600 series has. I would, therefore, probably recommend the 705 over either the 603 or 604, given your wife's preferences and your amp's specifications. The 604 will have a fuller sound than the 705 will, but it will also lack some detail.

Pair the 705's with a good sub and you should be okay.

[csuzor]

Definitely buy the 705 from your choices. For classical music, you can probably even live without the sub for some time, and that is a good next step.
I compared the 603/604 to the 705 and 704, and both 70x are far superior, especially mid and high range (mandatory for classical).
Later, you can buy additional speakers in the 70x series for surround sound, hugely beneficial for classic music.

[bigburner]

I owned a pair of B&W DM610i speakers for 10 years, and I loved those babies. When I upgraded to B&W CDM9NT speakers two years ago I knew that I had made a big improvement, but it took me 18 months to get to love them. The main issue was the brightness of the CDM9NTs compared to the warmness of the DM610i speakers. This changed once the CDM9NTs were broken in.

Recently I listened to the 703s at my local B&W dealer, and they are very, very similar to the CDM9NTs in their specs and sound. So if you come across a pair of CDM9NTs, give them a go because they will be a lot cheaper than the 703s (because they are now discontinued - the 703s replaced them).

Happy as I am with the CDM9NTs, they don't have enough bass if you like listening to music at volume. No small-woofer speakers do, IMHO. To fill this gap I recently bought an ASW750 sub which has made a huge difference to my system. So you might like to consider the addition of a sub as part of your upgrade.

By the way, classical music benefits from a sub too; there's plenty of bass in an orchestra!

[PewterTA]

Make sure you upgrade your AMP.

That Denon, if it's the model I'm thinking of which does 65/100watts, will not push the 705s to sound that great.

If you don't plan on upgrading your Denon, I would stick with the 603/604s as they will sound better with the Denon. If you plan to get an amp at some point I'd then go with the 705s...

Course I'd push the 805s then.

[bebo]

Everybody: thanks for responding

As for PewterTA:

Yep, I read that the 705' power handling indicates 50-120 W (8 ohm); but I don't understand you're conclusion: the 603 indicates 25-150 therefore remains also a lot of range left in the upper part... (and the 604 even 25-200 W. So I believe the 604 also will fail?).

Nevertheless: in what way do you think I will hear the difference with an more powerfull amp ?

Now I'm using the Denon PMA 680R.

Upgrading the amplifier in what way would your recommend ? Would 80 W make any difference or should upgrading bring more W ? (Denon offers with integrated amp's 70 and 80W (8 ohm)..... or 90, 100 and 120 W as surround receiver)

[RebelMan]

I would have to partially disagree with Dan (PewterTA) on this one. The SPL for the 600's is 90db vs 89db for the 705's so they maybe slightly easier to drive. However, you need to keep in mind that music is dynamic. The 600's have a "minimum" impedence of 3 ohms! This will cause much higher demands on your amp and may push it into (high side) distortion levels sooner than the 705's will as they are rated for a more conservative 4.6 ohms. The power "reserves" of your amp are far more important than what it is rated for continuous delivery.

As I said before, you will be better off (power wise) with the 705's and the amp you have now than you would be with the 603 or 604.

When the time comes, upgrade to an amp that can deliver 100 watts of continuous power (or more) and has headroom rated for 3db or higher. This will cover most, if not all, of what the 705's would need and will give you some breathing room should you decide to upgrade your speakers again.

[bebo]

Hello all,

I like these differences in opinion in forums like this, it helps broaden the horizon !

However - RebelMan - .... I quite don't understand what your saying... I understand that the fact that there is a different minimum impedence is relevant but I'm not technical enough to understand; could you explain it in simple English ? I'm asking because the power handling of the amp is higher at 4 ohm (100W in stead of 65W at 8 ohm) so I would say that at 4 ohm the amp will have more 'power' left ? And anyway, the speakers will perform/use (I don't know how to call it) at 8 ohm because there's a match with the amp ?

What do you mean with 'headroom' rated with 3db or higher ?

Earlier you (as others) suggested to use a good sub in combination with the 705's. I've suggested it to my wife... she asked what I meant and I showed her the picture of the ASW 700; she looked at the dimensions and told me 'No way'. So I'm afraid that won't work. But then again: I compared the spec's of the DM 310 I'm now using and those of the 705. The frequency range of the 705 is -6dB at 43Hz and 50kHz. With the DM 310 it's -6dB at 53Hz and 30 kHz. So I will gain in the lower range anyway substantially ? (of course I'm not knowing what I'm missing right now...) and better quality overall. Or should I consider buying the 603 or 604 in stead ?

[csuzor]

bebo, my wife has also told me '"no way" to the sub, unless I can hide it somewhere! One day, i'll just put one in the living room, and just accept a verbal beating for a short time before she accepts it!

In the meantime, I bought the 704, small enough to be acceptable to my wife, and much better bass response than 705... I raised them off the floor 5 inches with some wooden feet, and the bass is enough to enjoy the music as it is.

[Ash]

I have the N805 as main and 705 as surround.

I would recommend the 705 over the other options you had. The 705 are comparible in performance to the N805s. It has the same taste in respect to the delivery of music (however, still the 805 are better). You will be very happy with the 705, but those speakers definatly need a sub to get the most out of music. I think you are missing so much without one.
I also had alot of difficulties with my wife regarding the sub (especially, ASW 1000 a very ugly sub compared to the ASW750) and then the (surround speakers,), she hates them. However, There is no choice because I'm having those items in my house, I accept the occational annoying comments regarding this topic, but its worth it. (think about it).

[RebelMan]

bebo,

In simple terms impedance refers to the resistance of electrical (current) flow in a circuit, and is measured in ohms. Higher impedance causes less flow and lower impedance causes more flow. This value can very (between 8 and 4.6 ohms in the case of the 705s) and is primarily driven by the make up of the speaker's internal crossover circuits.

The less impedance your amp sees, from your speakers, the more current it will need to deliver. In the case of the 705s, an 8 ohm load may need 120 watts of power. When this drops to 4.6 ohms, the power needed may go up to 200 watts. (As a general rule you can estimate the power needed as follows... half of the speaker impedance = double the amp power. This is why amp and speaker matching is so crucial.

Even though your amp could drive the 705s with an 4.6 ohm load it is not well matched. However, it would be less taxing than the 603 or 604 would.

Headroom is simply the amount of additional power your amp could deliver "on demand", and is measured in decibels (dB). A Music signal is graphed like a wave with peaks and valleys. Some peaks are higher than others. When your amp sees the high peaks and the needs of your speaker (at that given moment) it must be capable of delivering the power necessary to allow the speaker to convert the signal into sound, otherwise "clipping" will set in and that is very bad!

Every 3dB of volume (headroom) requires a doubling of power. Therefore, an amp that has 3dB of headroom and is rated for 65 watts of continuous power (into an 8 ohm load) would be capable of producing 130 watts of power. This would be enough power to meet the demands of the 705's, but only if your amp has 3dB (or more) of headroom.

This whole matter becomes further exaggerated when you factor in distortion issues. But I won't go into that here.

You are far less likely to ruin a speaker that uses an over powered amp than you would an under powered one. Not to mention that the sound will be better because the signal is cleaner.

I probably oversimplified this explanation, but I hope it clears some things up.

[bebo]

RebelMan,

Thanks, your explanation is very clear; I understand (I think ).

However one question remains ... (how) is it possible to know how many headroom the amp has ? I can find something about distortion (THD) in the technical datasheet but nothing that looks like headroom.... On the internet I also can't find such data when I look at technical datasheet...

[RebelMan]

I am not surprised. Usually this information is not displayed on spec sheets by many manufacturers and for obvious reasons. It reveals to the consumer how good that particular amp really is. I suggest that you contact the manufacturer and ask them when you find an amp you are interested in.

I stated that you should look for an amp that has about 100 watts (for an 8 ohm load) of power and 3dB (or more) of headroom (sometimes referred to as dynamic headroom) to properly drive the 705s. You could, however, go with a 120 watt amp that has say 2.0 dB of headroom. There is more than one solution here.

Needless to say, when you are ready to shop for a (solid state) amp, the three most important things to look for are... (1) Continuous Power (per given load), (2) Dynamic Headroom, and (3) Damping Factor.

This is not to say that you should ignore things like frequency response, signal to noise ratios, and distortion levels. However, this is to say that many solid state amps are so good now days that you can put less importance on them.

[bebo]

Ok, thanks !