Grf-r's or lockwood majors? (diy) [Archive]

adrian

07-10-2011, 11:58

Hi Yer

Adrian here.Still in process of moving............Hi Fi temporarily on hold BUT..................

having not got anywhere with finding DIY plans or old empty pair of Lockwood Majors I have been reading SpeedySteve's great write up of the buiding and playback sound of his GRF=R's again.

What did put me off a bit ,as I was very keen to build a set of GRF's at one time,was a review of DIY GRF's some informed person had built(can't remember where I saw it now) and they dismissed what they had built as having '' the usual back loaded horn problems''.

Steve thought they were great.Got a bit confused at that point.

That's when I got into the Lockwood Majors idea,again.

Have you got any thoughts on this ? Way forward ? :)

REGARDS
ADRIAN

ps I have my newly reconed hpd 15'' 8 bolt -hole alnicos ( to prestige spec.) by Lockwood.

DSJR

07-10-2011, 13:34

GRF spec cabinets may well sell on easily in years to come, but who outside of immediate "fandom" has heard of Lockwood Majors, excellent as the revamped boxes actually are?

T'would be interesting to see what Marco thinks :scratch:

RotaryConnection

08-10-2011, 10:20

Take the negative comments about the GRF-R design with a (large) pinch of salt.
From my own experience and talking with other owners, we could only conclude that there was some flaw in his methodology/construction.
Or a room interaction..
Or maybe an ear/brain interface fault!! ;)
(Kidding, his own build looked very cool indeed.)
They are easily the best speakers I've owned-effortless musical enjoyment.
Corner units or even Jensen Imperials would probably give even better performance but no room or approval from the Mrs, so till we move to the country..
I love them.
Adrian-have we spoken via email before?
If so, get in touch, I've been really busy with family life recently.

Marco

09-10-2011, 12:49

Hi 'RC',

Could you please add your real first name to your profile? This is now required of all members - ta! :)

I'll get to this thread in detail later.

Marco.

RotaryConnection

09-10-2011, 13:46

No worries, added.

Marco

09-10-2011, 14:18

Cheers, Gareth! :cool:

Marco.

vencel

10-10-2011, 10:57

Aren't thw GRFs much bigger than the Majors?
I was also thinking of building a bigger cabinet for my Golds (currently they are in a Lancaster cabinet) and would love to build the Majors but unfortunately I could not find any construction plan for them.
I am very curious if the GRFs or the Majors sound better.
Any opinion?

adrian

10-10-2011, 14:48

Hi Gareth

Thanks for the encouraging reply. Don't THINK we have been in touch by e mail before but e mail me anytime.

I would like to build a set of GRF-R's as ,for once I wouldn't be outside the loop with a project.You can get info ,and refer back and talk to other owners/builders.
I 've never had a set of back loaded horns.
I have been involved with other sound stuff that I have constructed , built ,put together etc.,and been really isolated.All worked out though, but takes a lot longer.Don't want that again.

Hope you don't think I'm being a pain but could you give me a bit more on the GRF-R's,bottom end ,how they perform etc.Overall sound compared to bass reflex,as I can see you really know these cabs.I am genuinely interested. I do like the concept of the grf's not distorting and 'going' with the power as the volume increases.It would also be a very nice project to actually build something that is a bit different to the norm.
I wonder why ,they weren't favoured as studio monitors?

I rememeber being blasted by a set of Lockwood Majors in a London studio we once recorded in.

Look forward to a bit more 'discuss' on Tannoy GRF-R's.
Vencel,The GRF-R's are a similar size to the Lockwoods.

Moving very soon now,will have all the facilities for hi fi...... DE T A T C H E D ......My lifes ambition.

See you all,and thanks

REGARDS

ADRIAN

RotaryConnection

10-10-2011, 16:51

Laszlo-I don't think i've heard a pair of Majors and certainly not ones that have been 'worked on' like Marcos' so couldn't really comment.
I'd imagine there'd be more similarities than differences though wouldn't there?
Size-wise, mine measure 61x106x42cm deep.
I've added a couple of pics, one with the fireplace to try and give a sense of scale.
Adrian-sorry if I'm muddling you with someone else.
Very difficult to answer your questions meaningfully as we probably have very different sets of references.
But anyway, the bass is fast, detailed and perfectly adequate for my medium sized living room. Goes down to low 30's I should think, though I haven't borrowed gear to measure them specifically.
I haven't cared much for the kind of bass that other ported enclosures I've owned presented-a bit sluggish and 'chuffy'. These don't share that quality.
I listen to a lot of different music and I'm quite happy how these speakers present the recordings, whether it's classical chamber, rock, disco or electronic.
Get in touch if you want to ask anything.
PS Sorry the pics are a bit big!

http://i263.photobucket.com/albums/ii130/garyowen67/Mobile%20Uploads/1.jpg

http://i263.photobucket.com/albums/ii130/garyowen67/Mobile%20Uploads/2.jpg

RotaryConnection

10-10-2011, 17:49

Ps Just been listening to Invisible Limits by Tangerine Dream on Stratosfear, which is an album I first owned around thirty years ago and know very well.
There is a crescendo leading to a clanging bell-sounded bloody awesome with the amp turned up!
Fantastic tone, detail and imaging to both acoustic and electric guitars, piano and the Moog sequence lines that follow.
As good as I've ever heard it and gave me a 'hairs standing up on the neck' moment.
(Original issue cd used)

adrian

10-10-2011, 18:03

Hi Gareth

Many thanks for the reply AND the pictures.Your GRFs look amazing. The sound you describe must be great. Do I see a Prestige recone in there?Blueish colour. Did you construct these cabs yourself? Getting keen again now.Must start to study up on construction method.

REGARDS
ADRIAN

Reid Malenfant

10-10-2011, 18:08

Hi Gareth, i have a question for you if you don't mind me asking :)

Do you find that there are dips & peaks in the response near the low frequency cutoff? The only reason i'm asking is simply because forshortened horns (which is no doubt what that must be) tend to exhibit this behaviour. It'd be interesting to know the type of expansion used (exponential, tractrix, hyperbolic etc) & what the low frequency cut off of that horn was meant to be at the design stage :scratch:

The mouth looks kind of tiny to make much difference at say 35Hz, but then again the driver is pretty much designed to hit those kind of notes in a properly designed reflex so i'm just wondering how well that rear loaded horn works?

A GRF Autograph on the other hand you can see how the corner helps carry on the mouth to a certain extent & no doubt the Pi/2 loading helps even more ;)

RotaryConnection

10-10-2011, 18:39

Adrian-they are not so sympathetic to poor recordings tbh, but feed them with decent fare and they sound quite good really. :)
Lockwood cone/surround and crossover yes.
They were made for me by Steve Foster who posts here and over on HWW-he did a super job on them.
Mark-I'm a listener rather than measurer, I'd have to do some reading-up to try and answer your questions properly, though I know there are detailed explanations of their specification and design about as I've come across them before elsewhere.
I'm sure frequency graphs would show up all sorts of issues, be interesting to see but I don't think would detract from my enjoyment of music through them.

Reid Malenfant

10-10-2011, 18:46

:rolleyes: I should have thought about it before i typed actually ;) Sorry Gareth.

I'm just wondering you see if the shortened horn gives the extra gain that a reflex would but without the problems that come with them. Obviously the rear horn will add to the output but not by a great deal due to how short it is & the mouth size. However it may be a rather clever compromise is what i'm wondering :scratch:

Or in other words there may be method in the madness :eyebrows:

RotaryConnection

10-10-2011, 19:17

Definitely!
I'm not sure it adds a great deal but what is there sounds good.

adrian

11-10-2011, 07:34

Hi All

There is the school of thought that specs. on paper that should sound spectacular sometimes don't,and vice versa.I know the l lengths some enthusiasts go to incorporate massive bass horn enclosures into their houses and with the GRF-R bass section,it is comparitively a very small area.Yet owners say it sounds GREAT.I would have thought Tannoy of that time ,selling what would have been a very expensive esoteric item for the priveliged few ,despite cabinet design not particularly being their 'thing' ,would have had something in the design to make it work. A different take on what we expect now? But owners love them now? The specs maybe are suspect technically ,but it does look like,that despite this,they are working just fine. Just trying to take in some views on the GRF'R's. I suspect I would love them,like Gareth and co.

REGARDS

ADRIAN

aquapiranha

11-10-2011, 21:05

I tried and failed to find plans for the Lockwood Major for aomeone else, and along the way found various approaches to cabinet design for the MG15 including the GRF-R approach and bass reflex plus copies of the Canterburys, which I believe have a variable port (slot) making them a BR. It seems there are lots of differing opinions about what is best as you might imagine, but in the end I would say it depends on space, and often WAF. There are some good designs here..

http://www.hilberink.nl/speaker.htm

adrian

12-10-2011, 13:02

Hi Mr. Aqua and all

It's difficult to know what to put your time and cash into when you get into speakerbuilding. My WAF is no problem.She don't mind.She doesn't understand any of it,but likes to hear it!!.She does know that big speakers are special though.(funny how MOST females have no inclination towards electronics ,speakers and all that) Soon to have plenty of space ,also.

So I'm not limited, within reason,to what I build in the way of cabs.(mind you, I know about JENSEN IMPERIALS big!!!)
What happened was,I unexpectedly got given an old mates Tannoy Berkelys in return for work I did for him. They were pro built copies with Tannoy 15'' hpd 8 hole.,in need of restoration. I got Lockwood to do a Prestige on them.I rememeber when he got these ,back in about '74.Used them as studio monitors.

I also got hold of some superb amplification for them,100 wpc monoblocs JLH's.I briefly tried these out with the Tannoys,before packing up for the house move,and ............Wow,just great!!
So I gets me to thinkin' you have to go to the next level,as the Berkely CABS are generally seen to be lacking.

Thanks Folk for your replies
Regards
ADRIAN

RotaryConnection

12-10-2011, 13:19

Adrian-Imperials are the cabinet speakers that made the biggest impression on me when I heard a pair playing old rock n' roll singles at a rave a long time ago.
If you've got the room and greenlight from the Mrs..
I believe I read somewhere that Nelson Pass is playing with some in such a cab at the moment too so maybe there's some mileage in it.

adrian

12-10-2011, 16:20

Hi Gareth
If I DID have the courage to build JENSEN IMPERIALS, what did it for me was those guys in the US ,who developed these things up from the originals ,did state that in rooms under 24' by 24' they didn't work properly.I was a bit dissapointed to read that.There may be a scale down option. When I was looking into this self same subject ,few years back,someone on a forum somewhere,introduced me to JI's.Might have been you?
Wonder what the original market for JI's was.Huge US living rooms I suppose.

So I think I'll go back and have a look at the Tannoy site.I used to love that,so interesting.Thanks for the link.

REGARDS

ADRIAN

RotaryConnection

12-10-2011, 17:06

True, true..Go open-plan??
People have down-scaled Imperials before, but then I suppose you'd end up with something very akin to a GRF..

The Black Adder

13-10-2011, 17:48

THIS THREAD IS USELESS WITHOUT DIMENSION PLANS!!!

:eek:

adrian

13-10-2011, 20:34

Hi Black Adder

Sort of still talking about the general merits/disadvantages of 3 different cabs so far.If you aren't familiar with the size of the JENSEN IMPERIALS ,they are 3' wide 5 ' high and 2' deep. Huge. I think they would even be too big for ME.

I can't put up pictures as yet,but which plans would you like to see,as and when I get that sorted out.
You heared a Tannoy GRF-R? Any opinions if you did?

REGARDS
ADRIAN

aquapiranha

13-10-2011, 22:17

THIS THREAD IS USELESS WITHOUT DIMENSION PLANS!!!

:eek:

Jensen Imperial

http://www.dcaudiodiy.com/jensen_imperial/page_11.jpg

And also..

http://www.dcaudiodiy.com/jensen_imperial/jensen_imperial.html

GRF-R

See the links to plans at the bottom of this page..

http://44bx.com/tannoy/grf.html

:)

adrian

13-10-2011, 22:45

hi aqua

Thats brilliant !!!

REGARDS

ADRIAN

aquapiranha

13-10-2011, 22:48

No problem Adrian. Bear in mind, for the Tannoy MG the cabinet of the Jensen would be the other way up to bring the driver higher. It can be used with a std. 15" bass driver and horn mid /treble that would normally go in the throat of the horn, as in the pics in the link, so in that case the bass driver would of course be at the bottom.

adrian

14-10-2011, 14:08

Hi All

With giant speakers like JI's, and the era they were made for,wouldn't that be the 'low powered tube amp-massive cabinet principle,or is there more to it than that, for use with modern(ish) amps.( also 24' by 24' min. room size recommended !)

So anything over say,10 watts would not be necessary,so excluding the purpose of modern powerful amps.
Perhaps by the time you are getting to what they(the JI's) are capable of with a modern amp you couldn't be in the same room,for the power they'd develop.
Be interesting to see what y'all think of that. What I'm saying is,it's possible to own those monster cabs and be no better of than something smaller. Or something like that anyway.
I always believe that if a set up of any sound system that is very different to the norm, or custom built,special, it has to 'live up' to how good it looks.

rgds

ADRIAN

adrian

14-10-2011, 16:09

Hi
If you want more on old JENSENS try this.It's worth the effort:

http://www.hifilit.com/hifilit/Jensen/Jensen.htm

REGARDS

ADRIAN

Marco

16-10-2011, 07:28

Hi Adrian,

That link doesn't work, mate....

Marco.

Thing Fish

16-10-2011, 07:55

I was going to make a joke about the 'stiffening member' in the top picture but thought better of it.

adrian

16-10-2011, 09:11

Hi Marco

You have to type it in.How do you make those links live? I know what you mean.Nothing worse than hitting a potentially interesting link and ...................nothing. Hate that.I will have to sort that out.
Also do you have to get permission to post up live links?

Regards

ADRIAN

Alex_UK

16-10-2011, 11:32

Adrian - there's a button with the world and a bit of chain - a link - click that, paste your url, rename it if you want - sorted! ;) (If the URL was correct, of course!)

Marco

16-10-2011, 16:01

adrian

16-10-2011, 16:58

Hi Marco and Alex

Big thanks for that.!!!

I don't know how you end up with the correct 'url' to target exactly what you want to link to.The one I put up was just a line of figures I copied from someone else.

Thanks for that,
if I can crack that last bit,...........

REARDS
Adrian