Suitable driver for 25 litre enclosure

[LeftHandFool]

Hi all,

What would be a good choice of full range driver to fit into a 25 litre enclosure?

I've acquired an old pair of Philips speakers which are rather handsome, but otherwise useless, and would like to pair them with my SET amp (putting out around 4W), and the OT has taps for 4/8/16 ohms.

The speakers internal dimensions are approx. 430x315x180mm (height x width x depth), they're currently 3-way, so a new baffle will be needed.

Budget is tight - max £300 for the pair - although cheaper is not a problem 😉

I've a well equipped workshop so the woodwork is not an issue - is there any milage in a pair of boxes this size?


Thanks,


Matt.

 

[planet10]

Alpair 12pw. 2 x A10x, A12p, P7.

FF225wk (but needs a tweeter). Small for the FA22. FA17 maybe but needs the top tamed.

Likely many others.

dave

 

[LeftHandFool]

Hi Dave,

Thanks for the advice. If I'm reading you correctly, either a single Markaudio Alpair 12pw in each box, or a pair of either Alpair 10p/10.3, a pair of Alpair 12p or Pluvia 7s?

Would a single Pluvia 7 per enclosure be up to the task? Markaudio speakers fit my budget, but the SPL's are a little low (usually around 88/89dB), while similarly priced Fostex - for example - are often well into the 90's.

The FF225 I'd considered, but if it needs a tweeter that takes it off the bill for me. Who makes the FA22 and FA17?

Thanks,

Matt.

 

[LeftHandFool]

On a different note, I've been offered an old pair of Akai 13FP - 2AP's for next to nothing. Not much info about them, except that they may have been made by a company called Foster (which some say became Fostex?) in the 1970's.

Worth a punt (at £50 the pair), or a waste of money?

Matt.

 

[planet10]

Got pictures of the Akai Matt. Foster is the giant speaker manufacturer that Fostex is the boutique arm of. Some of th eold driver sare really good. But they do age. Value would be heavily dependent on condition. They would need to be measured to get an idea of where you would start.

Max volume for A12pw is about 35 litre, 17 litre for A10p/A12p, 13l litre for A10.3/P7.

You can always put bricks or sand at the bottom of the box to reduce its volume.

dave

 

[chrisb]

Are you constrained by amplifier output power? IIRC, Dave is one of several members here at first concerned about the apparent disadvantage inferred from the MA drivers’ raw sensitivity as compared to the Fostex. However, upon listening to them and “comparable” Fostex - most notably the pre WK series FE and particularly models such as FE126 & 166, many found that that single number on the spec sheet didn’t tell the whole story.

After playing around with several Fostex models in my own single driver based home systems, I switched over to MA close to 10yrs ago, and have been pretty happy so far. Currently running A10.3 as front row in 7.1 system; if looking to build today, I’d be inclined to look at the Pluvia11 or CHN110.

The FA17 and FA22 are by SEAS.

 

[planet10]

Right CHN-110 would be a good driver for your box. A really good driver. And a real bargain. Poke Stefan, he doesn’t have it listed.

You would need 3 P11s for that box.

dave

 

[waxx]

I would also says the CHN110 for that space, with a 7cm dia 20cm vent you got a good response to +/- 41Hz (F3) without counting room gain. And it's a great driver, a steal for the price they go for. I use a pair in an MLTL setup and it's almost on the same quality level as the much more expensive (basicly double price) Alpair 10.3 drivers i own... If you don't find them in the UK, you can get them here (in the Netherlands), altough i don't know the cost to import them to the UK (with the Brexit) now: Markaudio CHN-110 Silver woofer kopen - SoundImports

Edit: KJF Audio in the Uk has them: CHN-110 (single driver) | KJF Audio

 

[LeftHandFool]

Thanks for the advice everyone. I've bitten the bullet and bought a pair of CHN-110s.

@waxx - thanks for the link (and the recommendation), I'd somehow managed to miss KJF Audio. Better still they're on sale at present so I've saved a few quid too! Happy days.

 

[LeftHandFool]

Are you constrained by amplifier output power? IIRC, Dave is one of several members here at first concerned about the apparent disadvantage inferred from the MA drivers’ raw sensitivity as compared to the Fostex. However, upon listening to them and “comparable” Fostex - most notably the pre WK series FE and particularly models such as FE126 & 166, many found that that single number on the spec sheet didn’t tell the whole story.

I'm using a very simple diy SET - a single ECC81 driving a pair of EL84's into Hammond 1628SEA OT's. Output is circa 4W on paper. SPL has always been a concern, although as you say perhaps I've been more fixated on a single figure than necessary.
Ironically my experience with SPL is largely from a guitarists point of view, where I select the least efficient speakers for my amps, so I can push them harder at neighbour friendly levels.

My previous speaker history in the world of HiFi was a pair of Mission 752's which I've had forever, but didn't suit a SET in the slightest. A friend gave me his old pair of Q Acoustic 3050s, which are more efficient (from memory 89dB for the Missions, 92dB for the Qs) and sounded noticably louder, but not much better.

The Philips speakers were a gift from another friend. I've been charmed by their retro aesthetic, but having auditioned them for a few weeks now have not been charmed by their performance!

I'd had the idea in my head that SE amps needed room dominatingly massive speakers to flourish, but (having bothered to do the minimum of research!) I was pleasantly surprised to discover a 25 litre box with the right driver would be up to the task.
Fingers crossed for the CHN-110's.

Matt.

 

[waxx]

The Q acoustics are speced with 92dB sensivity, but in real world measurements it's more like 85dB average with peaks to 92dB. There were a lot of discussions about this speaker a decade ago on AVS when they came out. And the sound is also rather ragged, so i'm not surprised it's not sounding that good.

The CHN110 is measured 89dB, so with 4w it won't be fit for house parties (max 95dB for one/98dB for a pair on 1m), but most listening on normal levels is more between 60 and 90dB so that won't matter that much. And a single driver can better handle SET amps with a high output impendance than most multiway speakers..,

 

[planet10]

I'm using a very simple diy SET - a single ECC81 driving a pair of EL84's into Hammond 1628SEA OT's. Output is circa 4W on paper. SPL has always been a concern, although as you say perhaps I've been more fixated on a single figure than necessary.

Chris & i went on an intersting journey with SE EL84. Chris did the building, i provided some input and lots of listening.

We ended up with a very good pair of EL84 SE monobloks. Schade feedback, all poly caps, parafeed in the end. 4.9w at clipping.

Q Acoustic 3050s, which are more efficient (from memory 89dB for the Missions, 92dB for the Qs) and sounded noticably louder, but not much better...

I'd had the idea in my head that SE amps needed room dominatingly massive speakers to flourish, but (having bothered to do the minimum of research!) I was pleasantly surprised to discover a 25 litre box with the right driver would be up to the task

With a highish R_out an SE amp wants to see a speaker with flattish impedance and fairly efficient (the first likely more important than the rated efficiency).

Most speaker with XOs do not typically have flattish impedance. FRs with pole-piece caps have a nice impedance generally.

Your Q Acoustics impedance.

dave

 

[planet10]

The CHN110 is measured 89dB, so with 4w it won't be fit for house parties (max 95dB for one/98dB for a pair on 1m)

Given the typically way SE amps clip you are likely to be able to have peaks louder than that without audiable clipping.

In the real world you are unlikely to have too little power for most listening.

dave