Question about Cakewalk SONAR 4 Producer Edition for PC

2 Answers

I have a graaf 13.5b preamp feedback.

I have a graaf 13.5b preamp. I recently changed tubes. (sovtek 6922 to miniwat e88cc). When i use the input selector of my preamp i get a increasing hum from my speakers. I had no problem before the change of tubes. The techinician who checked the preamp found nothing wrong.
Please advise.

Posted by on

Ad

2 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Hi Geo,

Did you solve the problem, By the way I'm thinking buy a graaf 13.5B II, Can you tell me your experience? what you think about this preamp? it is quiet did the tubes make any noise (HUM, HISS) I have a very sensitive speakers (105db). Please hekp me to decide.

Posted on Mar 14, 2010

Ad
  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

One of the new tubes was faulty.

Posted on Jun 01, 2009

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Vox valvetronic amplifier static crackle


Check the speaker for a loose dustcap or separated spider.

Nov 20, 2013 | Audio Players & Recorders

1 Answer

6 yrs old,tubes replaced by 1st owner,perfect for first 8 months,then seems volume diminished, and now distorts when i play hard,playing soft no problem but when i strum hard it distorts


Sounds very much like low emission in the output tubes. Do you know if they were replaced with brand new or used ones? Very possibly the replacements, if they were brand new, are Chinese sourced, and sadly their quality is very low and the lifetime short. Russian Sovtek tubes are much better quality and worth paying more for. It's also important to replace output tubes in pairs, and matched pairs if possible. If the tubes age at different rates, the result is signal distortion, getting progressively worse as the valves age further, although seldom bad enough to be really objectionable - unless one of the tubes has pretty much died altogether while the other one is still performing reasonably well - in that case the symptom is pretty much exactly what you are describing.... :o)

Aug 23, 2013 | Traynor Ycv80 Custom Valve 4x10 Combo Amp...

1 Answer

Hum on channel 2.


I assume that the hum exists without any cables plugged into the input. If that is not the case, then make sure all input cables and source are using BALANCED lines. If the hum is present with no input cables, since this is a tube type preamp, the input tube for the bad channel is first suspect. It is likely a 12AX7 or 12AT7 type tube. Since there are two channels, the first thing is to SWAP the two channels and see if the hum moves with the tube... if it does replace the tube. I have seen another problem with preamps in general where bypass capacitors from either side of the XLR connectors to ground get zapped with static and one side shorts. This reduces the gain by 6 DB and leads to hum.

Aug 30, 2011 | Behringer MIC2200 MIC.-PRE-AMPLIFIER

1 Answer

My hot rods clean channel sounds great, but as soon as I go to overdrive, there is a loud squeeling sound that is only produced when the drive is on and makes different sounds the more i play with the...


I need you to run a few tests... one at a time.

Plug a set of headphones into the preamp output and simultaneously a set or a guitar or other low impedance device into the power amp input jack (this disconnects the power amp from the preamp)

Now, does the squealing noise appear in the headphone when in OD?

I also want you to test if the normal/bright switch has any effect when in normal configuration in OD?

If the normal bright switch has little effect on the squealing that helps isolate which stage is allowing the feedback.

I suspect that the source of the feedback is either a bad filter capacitor in the power to the preamp OR one of the contacts in the two realys that are for OD are making poor contact. These relays are switched "dry" which means there is little current to clean oxides off the contacts so they can make poor or no contact. An open contact would leave a grid floating as a high impedance "antenna" to pickup and feedback.

The first thing I would do if you had an oscilloscoppe would be to see that C36, a 22mfd 500 volt cap does not have high frequency ripple across it. One could try paralleling a new 22mfd cap across it to see if problem goes away... you will GUARANTEED have trouble finding a 500 volt one of these and have to settle for a 450 volt one which SHOULD be OK judging from the circuit. You can probably get one from Antique Radio supply... use Google to find them. Remember this amp has lethal voltages in it so if you are not adept at working on electronics of this type, best to take it to a shop that is.

Dec 11, 2010 | Fender Hot Rod Deluxe Guitar Combo...

2 Answers

My amp is making a high pitch noise almost like feed back. I only use the clean channel.When I tryed the other channel it is not working at all. Bad tube?


Bad tube? maybe
Try removing each tube 1 at a time starting at the first preamp (12ax7) If the noise stops after a particular tube is pulled replace that tube with a known good tube. Shut down the amp between tube pulls, Power tubes don't usually cause this problem but I'd pull them anyway,just remember they get very hot.
Make sure all tube shields are on and replaced after tube pull test
The most common cause of oscillation is a open or leaky filter cap,this would require a cap job and unless you have a good knowledge of tube electronics and the voltage dangers present,I wouldn't suggest doing it yourself.
Also if the output transformer was replaced or rewired or the negative feedback circuit was touched oscillation could occur also.
Make sure your guitar cables are in good shape, a cable with a bad shield can cause problems too.
Excessive noise can occur when one of the 1/4" input jacks shorting bars doesn't make contact to ground. A duumy plug would confirm this but you could also plug two guitars with good cables, into each input and see if the oscillation disappears.
Hope this helps

Nov 13, 2010 | Fender Hot Rod Deluxe Guitar Combo...

1 Answer

MY BASSMAN 100 MASTER VOL MODEL FROM 1972 HAS A HUM IN IT...? WHA


Well where do I begin. First, the polarity switch on the back might eliminate or reduce the hum, but by todays standards the way it functions is a deadly safety hazard (remember all the musicians that got fried in the '60's and early '70's?). That circuitry should be disabled and the unit retrofitted with a 3 prong power cord.

Next, the tube filiments are powered by AC voltage, and there is a control on the chassis for balancing it in order to reduce the hum. It could be toast or mis-adjusted. There could be a tube or other component problem causing your hum. The DC power supply could have faulty filter capacitors.

Another source of problems in these amps are the carbon resistors that introduce static noise in the audio. These should be changed to much better carbon film resistors.

If you are not comfortable working on electronic equipment with voltages in excess of 300VDC you should bring it to a pro audio repair shop.


Apr 16, 2009 | B&K AVR-202

1 Answer

How to connect PA mixer with built-in amp to feedbk dstryr unit?


The feedback unit should be connected between the pre-amp section and the power amp section. As you descrubed the ST-out and P.Amp IN are the ones to use.

Dan

Jan 22, 2009 | Audio Players & Recorders

1 Answer

Fender Vibro King Pilot light out??


Hi superleaddud

MOst probable, is that an output tube went west(decrease in vol), and in turn popped the fuse(pilotlight went out). It is always a decent first bet that this is what has happened. You get generally 6 months out of a set out output tubes if you use the amp often, and at gig levels every week. I would first check and replace the fuse, and then the output tubes. GT 6L6GE are factory for that amp, and always a fair bet to use the same to replace them. If you cant extend to the budget for the GT's, then Russian made (Sovtek) Electro Harmonix make a decent quality tube that sound good in guitar amps. . Always replace them as a pair, and buy them gain matched. Get the Grove Tubes from a music store, and the Electro Harmonix from an amp repair specialist. Happy to answer any question you may have about the problem. Cheers. A FixYa rating is a great reward for my assistance to you.

regards
robotek

Nov 24, 2008 | Audio Players & Recorders

Not finding what you are looking for?
Cakewalk SONAR 4 Producer Edition for PC Logo

Related Topics:

339 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cakewalk Computers & Internet Experts

Cindy Wells

Level 3 Expert

5161 Answers

kakima

Level 3 Expert

102366 Answers

Dan Shibata
Dan Shibata

Level 3 Expert

542 Answers

Are you a Cakewalk Computer and Internet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...