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horace
27-03-2010, 14:49
I've had these a little while now, so thought I'd let you have my initial impressions of them.

These are my first horns - quite a revelation they have been, too.

For those of you who don't already know (and I didn't...) the Jericho Horn design first appeared (I think) in a German audio magazine in the 1990s. My pair were built by fellow forum member Will (a very clever bloke, it must be said). The drive units are Fostex FF225K. Will recommended I add a pair of Fostex FT17H horn tweeters - I'm getting around to it and will get them when my funds recover...In the meantime, I'm using the speakers 'full range' with the single Fostex drivers covering the whole spectrum.

Now, if I were a proper audiophile, I would have set the speakers up using a measuring tape and spirit level, taking account of isolation needs, correct distances from walls, corners etc. I might even have analysed the room using a fancy digital gizmo and complex pc software...

... but I'm not really a proper audiophile, so I plonked em down where thay looked about right and plugged them in. In fairness, I will experiment with positioning and stuff - eventually.

So, how do they sound?

Bloody good.

Will warned me that horns have a shock factor for those used to 'ordinary' speakers. That turned out to be the case with me. It's hard to describe - the initial impression was one of hearing something very different. Bass breathed and filled the room, rather than sounding forced through a pipe. The overall impression was one of a system not having to try too hard. Music has realistic sounding scale and dynamics at last!

My OTL monoblocks struggled with my previous speakers, but barely break a sweat with the Jerichos - at 97 dB sensitivity (at least), that's hardly surprising I suppose.

Criticisms? Well, treble can be a bit fierce and a touch grainy, but that could be my rather 'live' room (I curse the day I bought laminate flooring and could do with some curtains!). Adding the Fostex tweeters might help too. My solid state preamp and Sony CDP could also be contributing factors. My valve preamp will be back in action soon though.

This morning, I played Bill Evans Sunday at the Village Vanguard. Scott LaFaro's bass filled the room and the sound of Evans' piano floated gracefully around it. I could hear every click of his fingernails on the keys (tbh I could have lived without hearing that, but hey ho...). It sounded like a real performance - that's it, in a nutshell.

If I ever change the Jerichos, odds on it will be for more horns. But we'll see. I'm keen to hear how the sound changes when the tweeters are added and I've had time to mess with setup.

Even my wife is impressed - and if you knew how unimpressed she is with the whole hifi obsession thing in general, you would know what a pleasant change that makes!

Before you say it: yes, system photos will be added soon.

I'll revisit this review when I get the new tweeters.

Cheers

Martin

Jonboy
27-03-2010, 15:52
Sounds like your on to a winner Martin, i have recently been impreesed with some of the horns i heard at Scalford, did you hear the home made horns in I-should-coco's room they blew me away.

I look forward to your pictures

horace
27-03-2010, 16:04
Sadly, my bid to go to Scalford was blocked :(. Maybe next year.

I'm looking for my camera.....

Cheers

Martin




Sounds like your on to a winner Martin, i have recently been impreesed with some of the horns i heard at Scalford, did you hear the home made horns in I-should-coco's room they blew me away.

I look forward to your pictures

Ali Tait
27-03-2010, 17:41
Great stuff Martin,they are rather nice are they not? I think the addition of the supertweeter will have quite a large subjective effect,not only on the treble strangely,but also on the mid and more so the bass.It's strange but true that supertweets seem to do this,at least to my ears.See what you think.

horace
27-03-2010, 19:31
Great stuff Martin,they are rather nice are they not? I think the addition of the supertweeter will have quite a large subjective effect,not only on the treble strangely,but also on the mid and more so the bass.It's strange but true that supertweets seem to do this,at least to my ears.See what you think.

Yes, Will has said the same. I'm saving my pennies!

Cheers

Martin

horace
28-03-2010, 22:19
I've just put my valve preamp back in the system.

Bloody hell, what a difference!

All of a sudden, I have music - the hardness and roughness was all due to the Cambridge preamp I was using while the valve pre was being fixed.


Rather chuffed...

Martin

The Vinyl Adventure
28-03-2010, 22:52
:worthless:

I'd love to hear some diy speakers like these! ... I just asked a mate with woodworking skills for a quote ...

horace
29-03-2010, 13:57
:worthless:

I'd love to hear some diy speakers like these! ... I just asked a mate with woodworking skills for a quote ...


Well worth the effort IMO. I don't have much experience of horns, but can certainly recommend the Jericho design. The plans are to be found on tinterweb.

I was up till three this morning, spinning tune after tune.

Amazing what a huge difference a change of preamp can make.

Cheers

Martin

Themis
30-03-2010, 08:52
Amazing what a huge difference a change of preamp can make.

Hi Martin, I've come to this conclusion, too. A preamp is essential to a system's voicing. I am even wondering sometimes whether it is more essential than what most think (ie: the source).

jandl100
04-04-2010, 07:10
Pics pics pics pics

.................. pics pics pics pics

Come on, get that camera out! :lol:

Is this them? http://www.plasmatweeter.de/jericho.htm

Ali Tait
04-04-2010, 08:30
Yep dats dem.Different colour though.

Will
04-04-2010, 15:56
For Jerry .....

http://i83.photobucket.com/albums/j317/willcowen/General031.jpg

Jonboy
04-04-2010, 16:26
Are those Fostex super tweeters Will running through L Pads?

Will
04-04-2010, 17:00
No they are Visaton horns with Fostex/Coral transformers (tvc)

.

jandl100
05-04-2010, 06:58
Thanks Will :) ... do I see an absence of those wizzer things on the drivers?

Marco
05-04-2010, 08:44
Hi Will,

Is that a Lenco I see there - what happened to the 401 with your superb 12" arm (or do you have both)? :)

Marco.

Will
05-04-2010, 11:20
Thanks Will :) ... do I see an absence of those wizzer things on the drivers?

These are now Martins Jericho's no whizzers dont like whizzers ...the Fostex 225k are very good maybe the smoothest of the fostex range and 96db also they drop like a stone at 11khz a real bonus when crossing over to a tweeter.

I had not listened to the Jericho's for about 9 months, what a shock I got setting them up for Martin they are very happy horns.

Marco I think that photo is from the first Owston meet a couple of years ago the Lenco has got to be the biggest bargain ever (best topend I've heard)

.

Marco
05-04-2010, 11:51
Lol - yes, I recognise the decor now!

Marco.

MartinT
12-04-2010, 06:43
Hi Martin, I've come to this conclusion, too. A preamp is essential to a system's voicing. I am even wondering sometimes whether it is more essential than what most think (ie: the source).

I agree with both of you. I thought when I had the Pass Labs X-1 preamp that I was already at the top of the curve and well into the area of diminished returns. However, the top of the range Pass XP-20 is so much better again that I am amazed. I am certain (having tried a few) that a power amp change would not give me nearly as much improvement, if any.

MartinT
12-04-2010, 06:47
I was going to comment negatively on the 'wallpaper table' supporting the valve gear until I twigged it was a show setup :)

horace
23-04-2010, 18:03
Well, a few more weeks down the line and I'm still very pleased with the Jerichos. I may have found their weakness though - very limited loudness before horrible distortion sets in. Maybe the drivers aren't designed to take much power?

I can live with it.

Unless, of course, my amps are the culprits.

Please lord, no more bills - my wallet is emptier than an empty thing :rolleyes:.

Martin

Ali Tait
23-04-2010, 18:29
I'd suggest it may be the amps,but how loud are you talking? The horns are pretty sensitive.

horace
24-04-2010, 08:43
Hmmm.

I don't think it's a sensitivity issue - I reckon I may simply have expected a little too much in terms of maximum SPL.

I'll have a play with the system and see if anything changes. I'm a bit suspicious of my preamp so will try substituting that first.

Cheers

Martin

Ali Tait
24-04-2010, 11:17
Possibly,yes.these drivers have a very limited Xmax,so ultimate volume is limited,but you must be listening at pretty high levels!

Will
24-04-2010, 13:50
Not the speakers Ali can you recall Nicks 300b amp with SteveS 300a's blasting the length at Owston.
Martin the preamp aint very good its the best place for DHT's.

.

horace
24-04-2010, 15:26
Not the speakers Ali can you recall Nicks 300b amp with SteveS 300a's blasting the length at Owston.
Martin the preamp aint very good its the best place for DHT's.

.

Hello Will.

I do think a change of preamp is on the cards - in the the meantime I have a solid state pre and a simple passive pot in a box (single input) which I will try.

All very odd. I still keep coming back to the same suspicion - that my power amps are very fussy when it comes to preamps. In fact, the only preamp I have tried with them that really worked well was an Eastern Electric Minimax. All the others have struggled to provide enough gain without adding distortion.

Quite frustrating.

Cheers

Martin

Ali Tait
24-04-2010, 16:37
Hi Will,yes I remember,that's why I asked how loud Martin was playing.Martin,can you borrow another pre to try? Could be an impedance mismatch-OTL's are quite sensitive to such things I think.If you search ebay for "Indeed hifi" they sell a valve buffer for about 50 quid which might be worth a try.

horace
24-04-2010, 19:21
Hi Will,yes I remember,that's why I asked how loud Martin was playing.Martin,can you borrow another pre to try? Could be an impedance mismatch-OTL's are quite sensitive to such things I think.If you search ebay for "Indeed hifi" they sell a valve buffer for about 50 quid which might be worth a try.


'Not as loud as I feel it ought to be' is the best answer I can come up with.

The problem is at its worst with heavily modulated female voices, which break up very badly even at very moderate listening levels. I did have the same problem (though to a much greater extent) with my last speakers too, so I agree the horns aren't to blame.

I will try some other preamps, but the EE minimax is the only one to have worked well so far (actually, Will's homebrew pre sounded very nice with it, but that's another story).
So, what is it about the minimax that makes it so different from all the others I have tried? and what's the deal with impedance?

Cheers

Martin

Ali Tait
24-04-2010, 19:50
Well practically an impedance mismatch can cause poor sound,especially at the frequency extremes,but from what you say,I don't think that's the problem.Pay Will to build you a decent pre!

jandl100
25-04-2010, 07:09
Have you tried a passive pre, Martin?

With those speakers I don't think you'll be needing a gain stage in the pre-amp. I've got an Eva2 LDR pre from DIY-Paradise, and it's really good. Only about £200 new. http://diyparadise.com/shop/index.php?main_page=product_info&cPath=18&products_id=113 They wre a fad item on the Wigwam for a while, so there's often 1 or 2 in the classifieds there! :)

Ali Tait
25-04-2010, 10:07
Yes,good idea Jerry,though the impedance issue may raise it's ugly head.

jandl100
25-04-2010, 10:46
I'm waiting on a packet from the States that will free up my Eva2 passive pre for while, and I'll then be happy to loan it to Martin to see if that does the biz with his OTLs. :)

horace
26-04-2010, 10:27
Have you tried a passive pre, Martin?

With those speakers I don't think you'll be needing a gain stage in the pre-amp. I've got an Eva2 LDR pre from DIY-Paradise, and it's really good. Only about £200 new. http://diyparadise.com/shop/index.php?main_page=product_info&cPath=18&products_id=113 They wre a fad item on the Wigwam for a while, so there's often 1 or 2 in the classifieds there! :)

Hi Jerry

Haven't tried a passive yet, but I do have a simple, one input 'Alps blue in a box' somewhere. That should give me an idea of how a passive would suit.

I simply can't spend anything at the moment, so I'm going to have to improvise.

To make matters worse, my cartridge is goosed. At this rate I'll be digging out my old walkman :rolleyes:.

Ah well, such is life.


Martin

jandl100
26-04-2010, 11:34
Don't go throwing good money after bad - enjoy what you've got, it sounds like it does fine 90%+ of the time.

See if you can get some pre-amp loaners from the folks on this fine forum to try! ;)

Hopefully, I'll be able to do you a loaner on the Eva2 passive in the near future.
__

Sorry to hear about your cartridge. :(

jandl100
27-04-2010, 09:49
Hi Martin - if you drop me a PM with your name & address I can loan you my Eva2 passive pre-amp now. :)

horace
27-04-2010, 14:29
Hi Martin - if you drop me a PM with your name & address I can loan you my Eva2 passive pre-amp now. :)

Perfect!

Thanks very much, Jerry - I really appreciate the offer.

Will drop you a line shortly..

Cheers

Martin

horace
29-04-2010, 15:38
Well, Jerry's EVA2 passive preamp arrived on loan this morning (thanks again, Jerry :)).

Wow, what a difference.

Total transformation, in fact.

Much better control, transparency and drive than any of the other preamps I have tried.

Curiously (can someone explain this please?), the little EVA passive doesn't struggle to drive the OTLs at all - the other active pres have required the volume pot to be turned up near the end of the range in order to produce sufficient welly, but the EVA goes plenty loud without breaking a sweat. So how does a passive outdo an active pre in that regard? All seems a bit counter-intuitive to me.

Anyway, I am very, very pleased with the sound I'm getting right now and am seriously considering getting my behind in gear to build a simple passive preamp of my own - something I've been 'getting round to' for too long.

Cheers

Martin

Ali Tait
29-04-2010, 16:37
It may be that the amp produces enough gain on it's own and doesn't nees the extra gain of an active pre,which may have been overdriving the amp,giving you the poor sound.Just a guess.

horace
29-04-2010, 18:04
It may be that the amp produces enough gain on it's own and doesn't nees the extra gain of an active pre,which may have been overdriving the amp,giving you the poor sound.Just a guess.

Could be - but does that explain having to turn the welly up to get sufficient volume? I would have expected the opposite to be true. But then again, I am famously dim when it comes to sciency stuff :).

I'm just glad it's all sounding so good now.

Cheers

Martin

jandl100
29-04-2010, 21:13
Yaaaaaaaaaaaaaaaaay !! Result. :)

I'm really pleased this has worked out so well ... and the good thing about passive pre's is that nice ones don't have to cost an arm and a leg!

Has it sorted the distortion you were getting on some music as well as sounding good?

horace
29-04-2010, 21:39
Yaaaaaaaaaaaaaaaaay !! Result. :)

I'm really pleased this has worked out so well ... and the good thing about passive pre's is that nice ones don't have to cost an arm and a leg!

Has it sorted the distortion you were getting on some music as well as sounding good?

Yep - no distortion at all now. Just sweet music, which is why we're all here.

:)

Martin

jandl100
30-04-2010, 07:02
Yep - no distortion at all now. Just sweet music, which is why we're all here.

:)

Martin

Hmmm ... this is all seriously strange. Although this does now (finally & thankfully!) tie in with my own experience with those OTL amps. They never put a foot wrong in the year or so that I had & loved them, after the initial sorting of the power supply sections by Champ Audio.

Just enjoy the music now ... and I look forward to your reports and views on the nuded Denon 103 you have just bought. :)

Ali Tait
30-04-2010, 08:51
One pre to consider-the TVC passive from Hi-Fi Collective.Rather good by all accounts.

horace
30-04-2010, 20:27
One pre to consider-the TVC passive from Hi-Fi Collective.Rather good by all accounts.

I have heard good things about the TVC, but tbh, I'm quite keen to try a more humble DIY preamp as this will be my first DIY project. I have an ALPS blue pot and some hookup wire. Just need some RCA sockets, an input selector and a case. Assuming it all works, I could upgrade to a stepped walletemptier at a later date.

It will, of course, sound utterly fantastic, cos I will have built it with my own hamfisted er, hands.

It will also have a big shiny knob.

Bling.

:)

Martin

Ali Tait
30-04-2010, 20:41
Yes,that'll work fine! I meant when you want something more permanent.

horace
30-04-2010, 21:27
Yes,that'll work fine! I meant when you want something more permanent.

Oh, I see what you mean.

The way my finances are heading, my permanent hifi solution will be a comb and penny whistle. The tunes might be shite, but the fidelity will be unbeatable :lol:

Martin

The Vinyl Adventure
30-04-2010, 21:38
:lol:

Ali Tait
30-04-2010, 21:41
:lolsign:

horace
08-05-2010, 01:08
I have found a temporary solution to the tweeter crisis - just bought a pair of these:

http://www.cad-audio.com/pr125t1.pdf


At just a touch over £15 (NOS), I reckon they have promise. They will have to be really quite awful not to be worth that....

We shall see :eyebrows:

Martin

MartinT
08-05-2010, 10:56
They're Audax so they can't be all bad.

horace
08-05-2010, 11:54
They're Audax so they can't be all bad.

That was my assumption too.

Better than no tweeters at all!

Martin

Ali Tait
08-05-2010, 12:08
They should be ok Martin.Are you getting L-pads too?

horace
08-05-2010, 12:27
They should be ok Martin.Are you getting L-pads too?

Um, er, L-pads?

Martin

Stratmangler
08-05-2010, 12:37
Um, er, L-pads?

Martin

Used to attenuate the tweeter level.
There's usually at least a capacitor in the circuit too, for LF rolloff.
https://www.wilmslow-audio.co.uk/catalog/index.php?cPath=49_149

Ali Tait
08-05-2010, 12:48
Yes,you need to match the tweeter's output to the main driver,otherwise you'll have too much,or too little treble.The easy way to do this is buy a tweeter that is more sensitive than the main driver,and use an L-pad(basically an adjustable resistor) to dial in the right amount of treble for your ears.

horace
08-05-2010, 13:32
Ah, I see.

Well, the FF225K main drivers are 8 ohm / 96dB sensitivity, which is the same figure as the tweeters.

Will was kind enough to provide me with a couple of lebgths of cable with a capacitor on the end (value 1.5).

I kinda thought the tweeter attenuation would work out about right? I suppose it wouldn't do any harm to be able to adjust the levels a bit, though it does put another component in the signal path.

I'll see how they sound and look at L-pads if I need them.

Be patient with me, I'm just a beginner :).

Cheers

Martin

Stratmangler
08-05-2010, 13:48
One thing you do need to take into consideration is that a single capacitor high pass filter has a very slow dropoff as you go lower down the frequencies.

A single cap will give LF rolloff of 3dB/octave.
If your crossover point is 10kHz, an octave below is 5kHz, two octaves 2.5kHz and so on.

The effects of a tweeter will still be all too audible at 6dB attenuation.

So there is a possibility that you may still need to put something in to attenuate the output level.
May being the operative word.

Ali Tait
08-05-2010, 15:15
Yes indeed.Give it a go though,and see what you think first.

horace
08-05-2010, 15:47
Thanks.

One day I hope to understand the science behind this hobby. Until then, I will have to rely on the generosity of those who know more than I...

The good thing about speakers (and turntables for that matter) is that you can see (or at least imagine) what's happening as they work. For me, that makes it much easier to begin to grasp the essentials of how they do what they do.

Should I think about building some simple enclosures for the tweeters or would propping them up on the top of the cabinets do fine?

Cheers

Martin

MartinT
08-05-2010, 16:26
They are probably sealed units so a small baffle with hole on top of the cabinet to hold them in place would be fine.

horace
08-05-2010, 16:57
They are probably sealed units so a small baffle with hole on top of the cabinet to hold them in place would be fine.

LOL - I was thinking of a couple of blobs of blu tac!

:)

Martin

Ali Tait
08-05-2010, 17:24
That'll do to see if you like what they do.When you want to mount them properly,as near the main driver as possible is preferable.

horace
11-05-2010, 19:12
The tweeters arrived today. I can safely say my £15 was well spent, as the improvement is dramatic.

Levels are just about right, so I won't need L-pads. If anything needs adjusting, the treble could perhaps do with a slight lift, but it sounds very nice as is.

Might need to improvise some mini baffles or enclosures for the tweeters as Mrs horace is not impressed by my blu tac solution! Read something somewhere about using small wooden bowls....

Cheers

Martin

Will
11-05-2010, 23:19
:)


.

horace
14-05-2010, 00:31
:)


.

If only I'd responded to your post yesterday. If I had, I would have done something like this :) :) :) :).

Unfortunately, I'm typing this with the acrid stench of melted mains transformer fresh in my nostrils. One of my OTLs decided to spontaneously combust tonight.

Oh well, the other one still works :(

How very, very annoying.

I would probably get banned for uttering the words I have in my head right now :steam:

And relax.

Time for bed.

I really don't have much luck with tubes.

:doh:

Martin

Ali Tait
14-05-2010, 05:39
Bad luck.That's the trouble with this Chinese stuff,the mains trannies are 220v,not enough for UK mains.Same thing happened to my 813 amp.If you can contact the maker,they will probably sell you another trannie,and when it's fitted,use a variac or bucking transformer to give you 220v.

MartinT
14-05-2010, 05:58
Yes, indeed, very bad luck. My mains voltage is damn near close to 250V much of the time and would give many Chinese amp designs a problem were it not for the fact that my regenerator is set to exactly 240V. Actually, that's one way you could solve the voltage issue and create clean mains at the same time.

horace
14-05-2010, 06:58
Well, I dunno about the voltages, but the transformer in the good amp has taps marked 260, 260, 230 and 115 volts....

The chances of getting in touch with the manufacturer are slim indeed - google search comes up with nada. I'm on my own, I suspect.

Are the transformers likely to be obtainable from elsewhere or will they be custom made?

If not, I may have to break my duck and (gulp) refer to my contents insurance policy.....

Absolutely gutted. I loved those amps :wah:

Cheers

Martin

horace
14-05-2010, 07:15
Looking on the bright side, I'm in an ideal position to rediscover the joys of monophonic sound.

And one speaker is easier to accommodate than two.

:rolleyes:

Martin

jandl100
14-05-2010, 08:36
Oh poo - really sorry to hear about this, Martin. :(

The amps were originally sorted (problem with high noise levels) by Champ Electronics http://www.chambonino.com/

Might be worth contacting them ... one transformer went tits up a while back when JB on Wigwam had them - Champ did a replacement job then .... it's just possible that the new tranny is the one that failed, in which case there might be some sort of warranty on it ...? Certainly worth contacting Champ.

horace
14-05-2010, 08:46
Oh poo - really sorry to hear about this, Martin. :(

The amps were originally sorted (problem with high noise levels) by Champ Electronics http://www.chambonino.com/

Might be worth contacting them ... one transformer went tits up a while back when JB on Wigwam had them - Champ did a replacement job then .... it's just possible that the new tranny is the one that failed, in which case there might be some sort of warranty on it ...? Certainly worth contacting Champ.

Thanks Jerry - that does suggest it will be repairable. I'll contact JB for more info on what he had done.


In the past, this would have been an excuse to try different amps, but I'm going to stick with these if they are fixable.


Cheers

Martin

horace
15-05-2010, 13:08
Update:

Lounge still smells of smoke (yuk).

Transformer still toast.

Insurance position uncertain - depends on cause, apparently. They want me to to find a local repairer to report on the cause of the failure. I am not optimistic.

I may have no amp, but at least my house didn't burn down ;)

Cheers

Martin