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Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment. |
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11th Feb 2019, 2:14 pm | #21 |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
Sorry Edward - I missed your post just now.
I've already checked the stylus in the Acos and replaced it with a new one. I'd also unclipped the cartridge and carefully extracted some compressed fluff from around the suspension - wishful thinking made me think it sounded better after that! Again, unscientifically, I'd played around with the EQ adjustments in the output from my phone and came to the conclusion that the Acos was giving too high an output at around 200Hz and lacking enough output at 4kHz and above (cutting and boosting those frequencies using the phone into the tape input substantially improved the sound from the Hacker). Could that be down to something like the suspension having stiffened over time? |
11th Feb 2019, 2:33 pm | #22 | ||
Dekatron
Join Date: Jul 2007
Location: Evesham, Worcestershire, UK.
Posts: 4,241
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Re: Hacker Gondolier sound lacking presence
Quote:
Honestly, if you're going to do it, this machine deserves better. The tweeter that I link to in that other thread is very cheap, but not at all bad for the money. Remember; the point of a crossover is not just to stop the tweeter getting fried - rather, it's about integrating the sound of the two drive units so that they sum together to produce a smooth frequency response. So even if a piezo unit didn't appear to require a crossover at a first glance, what if it produces a lot of output at the point where the main speaker is still generating a healthy output? You end up with an upper-midrange peak, which could be really quite unpleasant. So a high-pass filter on the tweeter (or a low-pass on the main unit) would be required. From what the OP says, no tweeter is required in this case. This gets us back to the eternal argument about these record player - some say that they seriously lack, but others say the opposite. I haven't heard one yet, but have a lot of experience with Hacker's other products - and accept that it could go either way. But personal preference is a big factor here, along with expectation and hearing. Until I've had a chance to audition (and measure) both speakers fitted to the Gondolier, I'm reserving judgement. |
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11th Feb 2019, 4:41 pm | #23 |
Octode
Join Date: Aug 2010
Location: Beeston, Leeds, West Yorkshire, UK.
Posts: 1,234
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Re: Hacker Gondolier sound lacking presence
Hi.
The GP96.1 cartridge rubber ears as you call them where the stylus sits are known to go hard over time and cause all sorts of wonderful and weird noises. I have a GP42 and GP45 which had the same cart both now have a BSR SC12M and both sound great. Gaz. Last edited by tracypaper; 11th Feb 2019 at 4:44 pm. Reason: corrected wrong cartridge number |
11th Feb 2019, 5:46 pm | #24 |
Dekatron
Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,528
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Re: Hacker Gondolier sound lacking presence
A bit of simulation around the Gondolier circuit's Rs and Cs suggests that the response is a bit odd. At "flat" there's a bit of a dropout (2dB or so) around 2kHz from the front end tone control circuit then a treble rolloff from about 4kHz from the 330pF across the first triode anode load. So that's already a bit woolly, but no worse than typical AM radio. Reducing the 330p.F might brighten things up, but it might also upset the loop stability. Some careful tweaking might be needed to do much good. Modifying the tone control at the front end to a passive Baxandall type and linking out the 47nF in the feedback loop might be one way to go without upsetting the loop time constants.
I don't have any useful valve models so I couldn't do the whole amp with its feedback loop but that looks like it would only add further gain rolloff at higher frequencies, though a look at the feedback network itself suggests little effect below about 40kHz, other than about 3dB/octave bass boost below 1kHz when the bass control is set to max.
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11th Feb 2019, 6:25 pm | #25 |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
If I've understood correctly Chris, that frequency response helps explain why Gondoliers are renowned for being a bit bass-heavy. Gaz's comment suggests the Acos might be accentuating that effect as the frequencies are imbalanced through 'stiff ears'. Have I just invented a new technical term there?
Let's see what the BSR cartridge does for mine. On the subject of which... I've been examining options for mounting the BSR. One is to adapt the Acos bracket as mentioned before (illustrated here http://www.graham-ophones.co.uk/comm...4632054792.jpg). Another has been suggested here by Nick (https://www.vintage-radio.net/forum/...t=93911&page=2) - i.e. a dab of superglue. Or, of course, I could fabricate something else! My question relates to the angle of the BSR once it's installed, as using any of those methods means the cartridge will be tilted forward. The Acos sits completely flat with the head of the tonearm, whereas the top of the BSR SC12M appears to be angled about 15 degrees to the front. Will that make any significant difference to the stylus angle, and if so should I be looking to shim the cartridge to keep it level? |
11th Feb 2019, 6:38 pm | #26 |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
Apologies for what turns out to have been a daft question. I've just realised that the way clip holds the GP96-1 has the effect of tilting it forward, so despite having a 'flat top' its stylus should effectively be at the same angle as the BSR.
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11th Feb 2019, 6:40 pm | #27 |
Heptode
Join Date: Jul 2008
Location: Hereford, UK.
Posts: 719
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Re: Hacker Gondolier sound lacking presence
If it were me I would try a bit of blutac first before going to a lot of trouble, to see if it has the desired effect on sound quality,
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11th Feb 2019, 6:48 pm | #28 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Hacker Gondolier sound lacking presence
Ah, glad to see you found the piece that I couldn't regarding a SC11/M bracket mod.
Ideally the stylus should have a -15 degree (negative rake) when viewed from the side. Now awaiting your next update!
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Edward. |
11th Feb 2019, 7:06 pm | #29 |
Hexode
Join Date: Dec 2018
Location: Sheffield, South Yorkshire, UK.
Posts: 364
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Re: Hacker Gondolier sound lacking presence
trust me you will not regret buying and fitting the bsr cartridge
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11th Feb 2019, 10:34 pm | #30 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
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Re: Hacker Gondolier sound lacking presence
i fitted BSR carts to both of mine by using a method i found here .A small bolt screwed into the cart and then screwed up into the arm once done its easy to push on the connectors with a pair of tweezers and it looks a whole lot neater
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11th Feb 2019, 11:55 pm | #31 |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
Very neat. Is the bolt going straight into the arm or through the little rectangular spacer?
Ùsing a jiffy bag to hold the tone arm up is probably the best tip I've seen yet! |
14th Feb 2019, 10:54 pm | #32 |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
Well the NOS BSR arrived safely, properly packaged and with nice clean properly-protected 'ears'.
I fitted it using a variant of Edward’s technique; I didn’t have a reamer or a grubscrew, so I cut the end off the original mounting bolt, enlarged the hole in the BSR a little, and Araldited it in as shown. I used a nut as a spacer and then screwed the whole thing onto the tone arm. The angle isn’t as severe as it appears on the pics – I was just trying to photograph as close as I could. The trickiest thing was getting the connectors back on with the whole thing in situ, so thanks for the tip about the tweezers! The result is impressive, and I’ve video’d a direct A/B comparison. Bearing in mind I’ve tried to keep everything consistent and that (as far as I can tell) all the original amp/speaker components are untouched the difference in clarity is very apparent – even when you take into account the crude mobile phone recording. https://youtu.be/2Qi304RgGzo I’ve got the stylus tracking at 4.2g, which seems to be giving good definition to my old ears on both this mono Ronnie Hilton and on new stereo pressings. Flipping over the stylus, it’s even rock steady on the most scratched and damaged 78s that I’ve got. Given this success I’ve no plans to carry out any amp/speaker component changes. The HF is fine for my taste given what I would have expected back in the day, and the machine really only sounds really bassy when it’s cranked up and I’m off axis right next to it. There’s a good, broad spread of sound all round the room. For now, I think everything is sorted. Many thanks for all the advice and encouragement. Laurie |
15th Feb 2019, 11:56 am | #33 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Hacker Gondolier sound lacking presence
A most impressive (and convincing) A-B demonstration and very well presented.
So there must have been some real deterioration of the Acos' elements/mounting mechanics over time. It also goes to show that even if an old crystal/ceramic maintains its apparent output level, it's range can really suffer. Quite a lesson for me too!
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Edward. |
15th Feb 2019, 6:43 pm | #34 |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
Correction - not Edward's technique - it was based on Maurice's: https://www.vintage-radio.net/forum/...d.php?t=128909
Thanks for the feedback, Edward. I've got another beaten up old SRP31D knocking around which has the original Sonotone 8T on it. Unfortunately the cartridge's tags are duff and its suspension seems knackered because of the way it likes skipping (despite tracking weight adj and change of stylus). When I refurb it I'll prob put an SC11M or 12M in (depends on what I can get). In the meantime, I thought it would be interesting to try the Acos from the Gondolier in it. I did a quick temporary mount with Blu-tack and it played fine - but it exhibited exactly the same symptoms as on the Hacker. Fuzzy, low-middy and with no definition. Nothing especially interesting about that other than to say it was interesting to get yet another confirmation that the Acos cartridge was past its prime. |
15th Feb 2019, 10:05 pm | #35 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
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Re: Hacker Gondolier sound lacking presence
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15th Feb 2019, 10:18 pm | #36 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
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Re: Hacker Gondolier sound lacking presence
I have four of those Acos carts all with the same problem as yours .I opened one of them and found the four connections very tarnished on the inside of the unit .I took them out and cleaned them using a pair of eye brow pluckers while i was in there i removed the rubber part that the needle rests in [it was leaning forward causing the plastic body of the cart to touch the records ]and turned it round so it was facing the other way .I then carefully put the whole thing back together with a small dab of Araldite and it worked a treat .really good output with plenty of Bass and treble .Its a pain to do but well worth it
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15th Feb 2019, 11:45 pm | #37 | |
Octode
Join Date: Apr 2016
Location: Ventnor, Isle of Wight, & Great Dunmow, Essex, UK.
Posts: 1,377
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Re: Hacker Gondolier sound lacking presence
Quote:
Brilliant record too- I've not heard that for years! Had to listen to it twice- how sad is that!! All the best Nick |
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16th Feb 2019, 12:31 am | #38 |
Heptode
Join Date: Mar 2003
Location: Cheltenham Spa, Gloucestershire, UK.
Posts: 525
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Re: Hacker Gondolier sound lacking presence
Im going to do the same with mine; its sound is wooly and no treble with its Acos fitted. I have a chinese ceramic cartridge I bought online with a diamond tip for £2 , Ill fit it with a bit of blu-tack & try it for sound temporarily.
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16th Feb 2019, 11:16 am | #39 | |
Triode
Join Date: Feb 2019
Location: Dereham, Norfolk, UK.
Posts: 29
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Re: Hacker Gondolier sound lacking presence
Quote:
I'd be interested to find out the results of ianj's cartridge swap. I've not been tempted by a Chinese cartridge as I want to retain easy 78 playability. And as for Nick - well, apart from being a great song, Windmill in Old Amsterdam is ideal for testing records as the stylus skips if the sound of the clog-dancing mice gets too loud. That's my excuse. |
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16th Feb 2019, 5:06 pm | #40 |
Pentode
Join Date: Jun 2011
Location: Berkshire, UK.
Posts: 124
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Re: Hacker Gondolier sound lacking presence
There is now a Chinese flip over cartridge, one make is by Banpa, it has the same mountings as the standard single sided version. It comes without a mounting bracket though. My Gondolier now runs a Stanton 500 cartridge and RIAA preamp. I run it with the treble full up, whereas the SC12M fitted previously was better, but the Stanton is kinder to my better records.
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