Impulse Horn loudspeakers?

[vinylengine]

It's a long shot but does anyone here know anything about Impulse H2 horns? They're huge things which weigh about 80kg (175lb) the pair and sound pretty awesome, but for a slight hardness which I'm certain is my Heybrook amplification trying too hard.

I'm looking for specs to help in the choice of a new (valve?) amp but any info would be interesting.

 

[MikE]

Tube amps... SET?

Sorry don't have any listening experience with them. The hardness you hear maybe due to the room, the amp driving them or just a the characther of this one horn itself. Perhaps there are some mods or driver replacements that may reduce that effect. Are you running a SS amp now? If so, a 300b or 2a3 would certainly shake out some of the rough edges. If you're going this (SET) route I'd figure out (listen) which tube type you prefer. I like the 45 but YMMV, and if the horns are only mid-90's efficient you may find them lacking with the 45 even if you like that sound (or lack of sound or coloration actually).

MikE

 

[vinylengine]

Are you running a SS amp now?

Hi,

I'm sure the hardness is from my SS amps, I've heard it in the past and managed to smooth them out by using different speakers and cables. The Heybrook Signature amps are about as solid state as they come, 148W a channel and massive current delivery - superb dynamics but need careful matching. They can sound fantastic but I think the H2's are building on the forwardness and the balance is not quite right (though still pretty impressive).

The only specs I have for the H2's are from a 1993 Audiophile magazine and state 100 WPC, 8 ohms and 94db sensitivity. I'm still waiting for a friend to bring round his WAD mono blocks to see if valves are the way to go. I just don't want to lose the strengths in the system - detail, imaging and dynamics.

I'm also a bit hacked off that Impulse removed all of the labels from the drivers - maybe I should photograph them (front and back) and hawk them around the forums to see if anyone can recognise them? I hate not knowing what drivers I'm listening to...

 

[Thatch_Ear]

All I could find was a review of the Ta'Us. 100 watts, 94 db, could be triamped. No pics but the review was a rave. I will post the URL if you like, but don't know if that model is simular to yours or not.

 

[vinylengine]

I think I just found the page -

http://www.vxm.com/21R.88.html

It sounds like the same drivers, triwire arrangement and similar size cabinet, except mine has the rear midrange enclosure open to the back and top of the speaker. The fibreglass Focal tweeter definately rings a bell. I'm not sure of his description of the speakers as ideal for apartment living though, unless you have an entire loft space to yourself!

Definately a bargain buy though

 

[Thatch_Ear]

Yes, that's the review allright. Sound like great speakers and that tubes will probably help with the overly bright aspect. And since they are in your place I hope the price was right.
Switching out tweeters shouldn't be hard if the tubes don't do all you hope for.

 

[michael w]

Hi JaS,

Wasn't the Impulse horn the chosen speaker of British hi fi guru/writer Jimmy Hughes ?

I recall him raving about the great sound when he reversed the speakers, tilted them downwards and had them bouncing the sound off his venetian blinds...

:


cheerio

 

[vinylengine]

Hi Michael,

I heard the same from Dave E over on AA. I haven't tried it myself as it sounds a bit potty but maybe when I have a quiet afternoon to spare

 

[Hornphile]

Impulse

Hi JaS
I cannot remember if it was the review of the Impulse H1 or HB1 that I read a decade ago. I think it must have been the H1. The reviewer said something at the end of the review that I have never seen before or since in any review. He said, “These are the finest speakers that I have ever listened to”. I cannot quote his exact words but it was something along those lines. I still have the magazine somewhere so I can look it up if you want more info. Yes it was a great review.

I remember that the system used a Focal tweeter. It also had a smallish midrange horn on top with a 3”- 4” driver and then a rear loaded 8” or something along those lines in a down firing bass horn. The bass driver had an enormous rear chamber behind the driver. Efficiency was very low in terms of horn standards. It was around 88 db.

The reviewer made one mod. He removed or added a resister in the crossover that made it sound much better. He complained about the balance of the tweeter to the rest of the frequency response. Might be the same as what you are experiencing. I think that the speaker could be bi or tri amped and he just stuck some resistors in the unused HF inputs. Need to read that review again.

I would love to hear that horn system. There is very little written about them. Would you mind taking some pictures so we can see?

Peace,
Hornphile

 

[vinylengine]

Hi Hornphile,

Great to hear the H1's got such a great review - the only published info I've managed to find out about my H2's is this short review in the 'audiophile selection' of UK Audiophile magazine from 1993:

" Impulse H2 £2350, 100WPC, 94db, 8ohm, 116x46x24 cm

Though smaller and cheaper than its elder brother, the H2 is anything but a scaled down version of the H1. Stereo imaging in particular is better than the H1's. Overall sound quality is superlative."

It sounds like it may be worth persevering with them, they sound good now but I'm still waiting to hear them with valves....

I'll snap a couple of pics this weekend when I can get hold of my camera. There nothing too special to look at but not a bad first foray into horns.

 

[Hornphile]

Impulse H2

Hi JaS,

I found the review. Hi-Fi Answers February 1989. Jip, it was called the H1. Maybe I can scan it and e-mail it to you. Might be interesting to read Jimmy’s views on the crossover mod.

Anyway, here is the quote ….Brrrr (drum roll) disssssh (cymbal) and I quote;

“Let me say in conclusion that the H1 has left me mightily impressed – so impressed that I have to say (deep breath) that they are the finest speakers I’ve ever heard.” END quote.
Quite an unusual thing for any reviewer to say.

It is a shame that 12 years later I still haven’t had the opportunity to listen to a pair of Impulse horn speakers. I get the impression that they were mainly distributed in the UK.


It is unfortunate that so relatively few people will in their lifetime get the opportunity to hear a really good horn system. I mean, we are all seeking the same thing, real live music, in whatever form that may come. It seems that there is a big move back to horn speakers. Unfortunately it is a slow process and more relevant amongst the DIY group than anywhere else. The result of this is that most horn systems are rather unique in their design in terms of what the DIYer had in mind, could afford or could make-work. These quite often incorporate little compromises here and there but hey, life is not perfect and neither are we. What Impulse gave the audiophile was a finished (completed) horn system, bass included. If you take the general complexity of bass horns into consideration, it is quite an accomplishment. One more thing. Some horns are so ugly that they should be R rated. I mean, my kids wont go near those Halloween looking things. You are fortunate, you have something in your house that people wont go, ”what the heck is that if I may ask”.

You were indeed fortunate to get those horns. Gee, I have never even heard these things and listen to what I am saying. Well, I have Jimmy to back me up. =0)

Are the covers removable on the H2’s? If they are please get us some inside shots.

Keep us posted on your progress.

Peace
Hornphile

 

[vinylengine]

Hi Johan,

If you get a chance I'd love to get a look at the review. It does sound like theres some big differences between the H1 and H2 but I'm sure they follow closely the same philosophy.

I must admit I'm impressed with the 'horn' sound in general, I've still got my Harlech 'transmission lines' to demo against and theres a natural, almost graceful air to the Impulse's reproduction which the Harlechs don't match up to. Bass is not quite as deep as my REL sub, but for some reason they sound better without it - the first speakers I've heard that sound full range without actually going the last mile. While the REL adds 'air' to all speakers I've used it with, the H2's sound effortless without. Of course they are nowhere near properly setup yet, positioning isn't optimal, system matching isn't right and whether I keep them only time will tell...

I'm not sure where Impulse where distributed, the guy I bought them off lived a matter of miles from there old factory units down in the big smoke so mine haven't travelled far at all.


"You are fortunate, you have something in your house that people wont go, ”what the heck is that if I may ask”. "

Unfortunately my partner finds them a little large, but I've assured her they will grow on her

 

[vinylengine]

Impulse H2 pictures for Hornphile

Not too good as I'm still waiting for my camera to come back from the shop, but it gives you the general idea

The Mid horn is mounted in a chamber at the back of the cabinet, with slots open to the rear and top (covered by the grill cloth). The sides of the horn are also open at the front through the grill cloth on the sides of the cabinet.

The remainder of the cabinet is a horn for the mid/bass unit on the front and opens at the base which is supported by 10mm spikes.

I've now had a chance to hear it with a friends WAD monoblocks (KEL 80?) and I'm even more unsure where to go from here. The midrange is the best I've heard with the valves in control, but for dynamics the Heybrooks still have it. Treble was also sweet almost to a fault, but (?) ruthlessly revealing of bad recordings - and I listen to a lot of poorly produced stuff. The bass seems to go deeper with my CD player than my Record deck, but the imaging with vinyl can be so holographic it's hard to walk away. The best I've heard but also the most frustrating - I'm rounding up all my gear and trying various combinations to hit the best compromise but all this substitution makes it hard to relax and take a balanced view. Boy this listening to music is hard work sonetimes.