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Crack;Bottlehead OTL - Page 295

post #4411 of 7978

Pics!!

post #4412 of 7978

Hi! Finished my Crack yesterday and had a listen. There are few things that disturb me a little. I try to give as much information as I can. 

When I finished soldering I did the resistance checks (every measurement was correct) and then voltage checks (also every measurment was correct). When I turn the amp on (with no DAC and laptop connected to it) and put my ear near the crack it hums and when I connect my headphones (HD700) in then the same hum comes through them. When I connect my laptop and dac (schiit modi) to it and turn on the music I hear crackling/popping. (like an old vinyl). Both the hum and crackling/popping sound is in both channels. I re-heated all the joints 3 times and everything is still the same. The hum increases when I turn the volume from 0% to 100%. I add some pics also. If anyone sees anything problematic or have some ideas what to test or measure then please share your thoughts. 


So, this is how my crack turned out :smile:

 






And now the other pictures

post #4413 of 7978
Quote:
Originally Posted by roguegeek View Post

Welp, got it all put together in one day. This included staining the wood and painting. I think it came out ok. The only thing that's missing is connecting the ground from the AC to the chassis because the #8 solder tab was missing. Sent over an email and hopefully they can get that part over as soon as possible. Tried to go find it from some local stores today, but no one carried anything like it. I'll try a couple more tomorrow and then, hopefully, I'll be able to test it.

A crimp on connection would work - the ones that have a round eye. You could then use a longer bolt and just use a nut to attach it to the chassis.
post #4414 of 7978

Does anyone have both tubes-13D5 Brimar longplate and Mullard CV4003 and do a little comparison please  ?

 

EDIT; CV4003 is pretty pricey and from this description 13D5 could be a better value 

I have one 13D5 and it does sound very good ,was wondering if this is true 

Quote:
 These are incredible tubes with a fine soundstage, clean top end with a touch of midrange warmth. Like the famed CV4003 but with more layers of detail and more delicate
 
quote from BRENT JESSEE RECORDING & SUPPLY, INC.

Edited by spacequeen7 - 3/30/14 at 7:21am
post #4415 of 7978
Quote:
Originally Posted by Klots View Post
 

Hi! Finished my Crack yesterday and had a listen. There are few things that disturb me a little. I try to give as much information as I can. 

When I finished soldering I did the resistance checks (every measurement was correct) and then voltage checks (also every measurment was correct). When I turn the amp on (with no DAC and laptop connected to it) and put my ear near the crack it hums and when I connect my headphones (HD700) in then the same hum comes through them. When I connect my laptop and dac (schiit modi) to it and turn on the music I hear crackling/popping. (like an old vinyl). Both the hum and crackling/popping sound is in both channels. I re-heated all the joints 3 times and everything is still the same. The hum increases when I turn the volume from 0% to 100%. I add some pics also. If anyone sees anything problematic or have some ideas what to test or measure then please share your thoughts.

 

The Crack is quiet good at picking up outside interference try rerouting some of you cables away from transformers, extension leads, wifi-routers etc and also put some twists in the rca cables that go from your dac to the amp. This cured the hum issues I had with my amp. Not sure about the crackling and popping perhaps a loose rca connection or a headphone jack connection issue? The bottlehead forum is the best place to resolve any teething problems.

post #4416 of 7978
Quote:
Originally Posted by JamieMcC View Post
 

 

The Crack is quiet good at picking up outside interference try rerouting some of you cables away from transformers, extension leads, wifi-routers etc and also put some twists in the rca cables that go from your dac to the amp. This cured the hum issues I had with my amp. Not sure about the crackling and popping perhaps a loose rca connection or a headphone jack connection issue? The bottlehead forum is the best place to resolve any teething problems.



I already tested with no routers, mobile phones, computers etc being around, no change. The rca cables dont have to be attached for the hum to appear. Headphone jack and rca connections are great. Maybe a bad tube? 

post #4417 of 7978
Quote:
Originally Posted by Klots View Post
 



I already tested with no routers, mobile phones, computers etc being around, no change. The rca cables dont have to be attached for the hum to appear. Headphone jack and rca connections are great. Maybe a bad tube? 


I have found that some tubes can cause hum or noise. More often it has happened with 6080 tubes Ive tried.

post #4418 of 7978
Quote:
Originally Posted by syphen606 View Post


A crimp on connection would work - the ones that have a round eye. You could then use a longer bolt and just use a nut to attach it to the chassis.

 

How about wrapping the wire around the bolt where the solder lug would have been installed and tightening that down?

post #4419 of 7978
Quote:
Originally Posted by Klots View Post
 



I already tested with no routers, mobile phones, computers etc being around, no change. The rca cables dont have to be attached for the hum to appear. Headphone jack and rca connections are great. Maybe a bad tube? 

I had few noises coming earlier ,..rerouted some wires around driver socket and most of it's  gone now ,the hum is related to tube -I would suggest swapping /trying another power tube ..5998 or 6080 doesn't matter it's about how micro-phonic particular tube is

before

 

 

 

 

and after 

 


Edited by spacequeen7 - 3/30/14 at 10:04am
post #4420 of 7978
Quote:
Originally Posted by Klots View Post
 


The rca cables dont have to be attached for the hum to appear. 

 

Same with mine.

 

Twist them up and give a try, it takes less than a minute to do so and its a easy thing to rule out, it just might work also. Like I said it worked for me and I know a few others who have resolved their hums by doing this.

post #4421 of 7978
Quote:
Originally Posted by JamieMcC View Post
 

 

Same with mine.

 

Twist them up and give a try, it takes less than a minute to do so and its a easy thing to rule out, it just might work also. Like I said it worked for me and I know a few others who have resolved their hums by doing this.

I will try that when I get my new rca cables next week. 

Quote:
Originally Posted by spacequeen7 View Post
 

I had few noises coming earlier ,..rerouted some wires around driver socket and most of it's  gone now ,the hum is related to tube -I would suggest swapping /trying another power tube ..5998 or 6080 doesn't matter it's about how micro-phonic particular tube is

before

 

 

 

 

and after 

 

 

 

6AS7/6AS7G/6AS7GA would be ok? I have to buy tubes from europe because no customs then and faster delivery.
post #4422 of 7978

^^ try posting on BH forum and see what the experts have to say before spending more $ ,you might have to check your voltages 

http://bottlehead.com/smf/index.php/board,24.0.html


Edited by spacequeen7 - 3/30/14 at 10:27am
post #4423 of 7978
Quote:
Originally Posted by spacequeen7 View Post
 

^^ try posting on BH forum and see what the experts have to say before spending more $ ,you might have to check your voltages 

http://bottlehead.com/smf/index.php/board,24.0.html


Thanks for the suggestion. Already made a post there. 

post #4424 of 7978

I live in England but if I pick up a Bottlehead Crack from the USA, running on 120 V, would a 120 V to 240 V transformer be all that is needed for it to work? Any damage likely to occur?

post #4425 of 7978
Quote:
Originally Posted by sotto123 View Post
 

I live in England but if I pick up a Bottlehead Crack from the USA, running on 120 V, would a 120 V to 240 V transformer be all that is needed for it to work? Any damage likely to occur?

On the bottlehead crack product page you will see a option to select a 240 transformer when ordering at no extra cost. The kit then arrives with transformer specified for uk use.

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