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Crack;Bottlehead OTL - Page 341

post #5101 of 7977

GEC Brown Base impressions:

 

From 45 minutes' listening, at 6am, this is a gorgeous thing. It's warmer and richer - tubier, even - than the 5998 but the detail is all there. It seems to bring the focus back to the mids, which really suits the HD650s. Also, the bass thumps like the stock Crack with a Mullard 6080 but with the extension and tightness of...well, there's no comparison with anything I've heard.

 

I've got to get to work now but looking forward to some extended listening this evening.

 

Edit: For example, Aphex Twin - Flim. There's a whole other level of richness to the synth decay which has never come through before. Boards of Canada...crikey.

post #5102 of 7977
The Smash DHT really needs to ship soon. The Quickie has set a high bar. Can't wait to see how the Smash is with the Crack.
post #5103 of 7977
Quote:
Originally Posted by Sonido View Post

The Smash DHT really needs to ship soon. The Quickie has set a high bar. Can't wait to see how the Smash is with the Crack.

:popcorn:

 

Can't wait for your impressions

post #5104 of 7977
Have just joined the modders' club.

I have added a switch onto the speedball that lets me select between different current outputs, resulting in a nice operating point for 12AU7, E80CC and 12BH7. Currently I have a Tungsram E80CC up front. With the 7236 the sound is a little harsh and forced. However, it balances beautifully with the GEC 6AS7G curved brown bass. I highly recommend this combination.
post #5105 of 7977
Quote:
Originally Posted by MoatsArt View Post

Have just joined the modders' club.

I have added a switch onto the speedball that lets me select between different current outputs, resulting in a nice operating point for 12AU7, E80CC and 12BH7. Currently I have a Tungsram E80CC up front. With the 7236 the sound is a little harsh and forced. However, it balances beautifully with the GEC 6AS7G curved brown bass. I highly recommend this combination.

 

Nathan the E80cc and GEC 6as7g is my favourite combination. I like what I'm hearing running the same combo now with those Epcos pio motor runs

 

I have tried four different PIO caps with the Crack so far and liked them all! I have some 100uf Solen films on the way also to try. 


Edited by JamieMcC - 5/22/14 at 4:18am
post #5106 of 7977

+1 on the Solen film caps. I got very good results with them. You should like them I would think. 

post #5107 of 7977

Swapped out the Hovlands Supercap bypasses to try for some Russian K71-7 Polystyrenes.

 

post #5108 of 7977
Quote:
Originally Posted by grizzlybeast View Post
 

is there supposed to be buzzing/humming at low levels with my crack/speedball?

 

If not what could be the problems. I had this with other amps and know its common but its a little bit louder on the crack/speedball.

 

I am thinking its the kind of tube I am using "RCA 6AS7G JAN Black Plates". The stock 6080 did this even worse. 

 

Could it be source related if you had it with previous amps? I would try to run the Crack without any source connected and using a shorting plug (a RCA jack with an around 500 Ohms resistor connecting ground to center). If it's dead quiet with a shorting plug, then it's your source (without shorting plugs and no source, there should or could be some humming). If it's not quiet, then I would try to move the Crack around, remove RFI source around and finally ask help at Bottlehead forum.

post #5109 of 7977

Time for some humble pie, about 6 months ago I tried bypassing my JFX films with the Jantzen Audio Superior Z-Cap and really didn't like the results very much.  Well I tried them earlier with the Epcos 100uf's and the effect was completely different with the pio caps the results was a great success the complete opposite of my earlier trials with the JFX.

 

 

Thought I would include a picture of some different construction types of film capacitor as its a chance to see how the sizes compare

 

Top in black a standard JFX 2.2uf film it has the largest capacitance of the three

 

Middle  Jantzen Audio Superior Z-Cap 0.47 uf these have the windings interweaved so effectively it takes two normal 0.47 winding to make one Jantzen Superior Z-cap

 

Bottom and largest physical size the Hovland Supercap 1uf these are constructed using the true film method so a winding of real metal foil is used in between layers of film rather than the just the normal thin metalized polypropylene film .

 

 

 


Edited by JamieMcC - 5/22/14 at 10:04am
post #5110 of 7977

Ok, my assessment of the GEC Brown Base vs. TS 5998:

 

These are both running, via rDAC, in a Speedball + Crack, with 100uF Mundorf output caps (only around 30hrs burn-in) and a Brimar E80CC with the resistor mod, into HD650s.

 

The most distinctive difference, and which I can see dictating preference, is that the 5998 has a slightly drier, superficially airier presentation while the GEC offers an extremely cohesive, rich and full presentation.

 

The 5998 does an amazing job at elevating the lead vocal/instrument and giving it its own space. It also seems to slightly lift the drum track and percussive details which give it a great sense of pace and energy. I want to air drum to pretty much everything. This lighter, airier presentation does mean that certain elements can come across as thin, including drums. Despite the level of detail, it's a very relaxing listen, you're excited by all the little flourishes but the presentation is so sweet. Bass is perfectly controlled, taut and extends deep. You can easily pick out all the bass notes and separate levels of mid/low/sub-bass. The mids also have a ton of detail and texture. There seems to be plenty of stereo movement of instruments. I absolutely love this tube in my set-up and can't say I bought the GEC for any reasons of dissatisfaction. Since I fitted the caps and gave them a little chance to burn in, this combo produced the best sounding music I've ever heard.

 

The brown base, on the other hand, is less ostentatious with its detail. The first thing you notice is emphatically not the imaging and percussive detail, it's the relative thickness of the sound. This is probably the warmest music has been since I fitted the Speedball. As I said above, my initial response was almost akin to listening to the Mullard 6080 powering the ECC82 in the stock Crack. It's obviously a whole other level above that, but in terms of bass impact, that was my previous reference point. And initially, while that was enjoyable, it seemed like a step backwards in one sense, because I'd been enjoying that exponential increase in imaging and detail with a few recent mods I'd done. It takes a little longer to realise that all those details are there, that you can unpick the entire track piece by piece if you want, that the decay and reverb are identifiable on every neatly separated element, it's just that the tube is not encouraging you to do that. It's presenting it all together in a very rich and cohesive package. As I said above, it's brought back the lushness of the lower mids which the 5998 keeps quite airy. On the other hand, this can mean that the music washes over you, it's so soothing and buttery smooth. Whereas the 5998 continually brings you back and competes for your attention with its brilliance, the GEC allows you to sink into the whole, pure engagement, confident that all the detail is there for the taking when you want it.

 

You listen to something like Birdland, which offers layers upon layers of rhythmic keys, glistening pads, bumping melodic bass, bright synths and delicate piano. One tube is constantly feeding you little treats and tasty morcels, the other lays out a glorious banquet and says 'serve yourself'.


Edited by grrraymond - 5/22/14 at 12:13pm
post #5111 of 7977

Graham, nice write up, I am pleased the tube made it to you safely and that your enjoying the GEC experience. :atsmile:

 

One of my favourite things about the GEC is how its handles vocals its just has a special way of conveying the subtleties of both male and female vocals its analytical side digs deep revealing nuances in tone and texture and can then deliver them them with either the upmost delicacy & fragility or all the gravel and rawness of a stained male rock vocal. Listening to females artists like Eva Cassidy can be spellbinding and just stop you dead in your tracks.

post #5112 of 7977
post #5113 of 7977

Thanks Jamie - ordered :)

 

Paul.

post #5114 of 7977

I've noticed sporadically over the past couple of months that the bass is sometimes slightly imbalanced in my 650s, I wasn't sure whether it was just in my head and I actually went to get my ears tested!

 

I'd switched cables and tried them with different sources, same problem. I thought they'd gone to the knackers yard but they'd always seem to right themselves. Anyway, this morning I've had nothing but grief from them so I took them all apart. One driver wasn't clipped in properly. Doh! Back to their best now :p

 

Feel free to disregard all my comments and analyses on here over the past six months...

post #5115 of 7977

I have been trying out a pair Solen made 100uf films in my Crack and found them to be very similar to JFX 100uf premium films.

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