Loop questions
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Loop questions
What is better , attive or passive loop?
There are big differences ?
what the quality e what defects?
Thanks
			
			
									
									There are big differences ?
what the quality e what defects?
Thanks
www.sae-audio.it
Handmade tube amplifiers inspired to Dumble sound!
						Handmade tube amplifiers inspired to Dumble sound!
Re: Loop questions
Depending upon the implementation, active is usable 99% of the times while passive seldom is.sergio wrote:What is better , attive or passive loop?
There are big differences ?
what the quality e what defects?
Thanks
Passive loops often have a high output impedance so just about anything you connect to the loop will load the circuit down. To make things worse, in the case of an amp like an ODS, the signal level at the passive loop wil be high and will not work with low level devices. Last, and the deal breaker most of the time, since you will have to pad down the signal sent to the effects, unless the device is very sophisticated, the loop will not have the capability to restore the gain level. So, while you may be able to make the passive loop work, you will end up with much less voume than the amp would otherwise be capable of.
Cheers,
Gil
Re: Loop questions
Many are using the active loop from Ironsounds with reportedly good results.
I bought one but haven't installed it yet.
$55 shipped.
			
			
									
									I bought one but haven't installed it yet.
$55 shipped.
Tom
Don't let that smoke out!
						Don't let that smoke out!
Re: Loop questions
Thanks Ayan , so ,you should recommend to choose the active model?
The old ODS haven't active loop , what do you think of this?
			
			
									
									The old ODS haven't active loop , what do you think of this?
www.sae-audio.it
Handmade tube amplifiers inspired to Dumble sound!
						Handmade tube amplifiers inspired to Dumble sound!
- glasman
 - Posts: 1446
 - Joined: Wed Jan 19, 2005 10:37 pm
 - Location: Afton, MN (St Croix River Valley)
 - Contact:
 
Re: Loop questions
This is why Dumble sold the Duimblator. Why build in what you can charge extra for.....sergio wrote:Thanks Ayan , so ,you should recommend to choose the active model?
The old ODS haven't active loop , what do you think of this?
  Located in the St Croix River Valley- Afton, MN
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
						About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
- glasman
 - Posts: 1446
 - Joined: Wed Jan 19, 2005 10:37 pm
 - Location: Afton, MN (St Croix River Valley)
 - Contact:
 
Re: Loop questions
And actually,  there are many people who prefer that there is no active loop in the amps.
			
			
									
									  Located in the St Croix River Valley- Afton, MN
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
						About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification
www.glaswerks.com
Re: Loop questions
So let me make sure I've got this straight (sorry if it's a silly question) -
When you use a Dlator with an ODS, you typically plug the "Preamp Out" into the input of the Dlator, then the output of the Dlator into the "Poweramp In"?
That would make sense, because I've never been able to find a use for those jacks before
			
			
									
									
						When you use a Dlator with an ODS, you typically plug the "Preamp Out" into the input of the Dlator, then the output of the Dlator into the "Poweramp In"?
That would make sense, because I've never been able to find a use for those jacks before
Re: Loop questions
No they are plugged into a passive loop on the ODS.
The Dumbleator creates a tube powered active loop if I'm not mistaken.
			
			
									
									The Dumbleator creates a tube powered active loop if I'm not mistaken.
Tom
Don't let that smoke out!
						Don't let that smoke out!
Re: Loop questions
Ah, makes sense.
Where exactly in the ODS circuit is the passive loop typically located? I'd like to build an amp with an active loop after the preamp and right before the PI
			
			
									
									
						Where exactly in the ODS circuit is the passive loop typically located? I'd like to build an amp with an active loop after the preamp and right before the PI
Re: Loop questions
Not real sure of what you are asking but, the loop on the D'Lites typically
connects at the grid cap of the PI and returns to the master volume wiper.
			
			
									
									connects at the grid cap of the PI and returns to the master volume wiper.
Tom
Don't let that smoke out!
						Don't let that smoke out!
Re: Loop questions
Thanks  
 
Sorry if it was a bit of a noob question, I just hadn't seen an ODS schematic with a loop on it before.
			
			
									
									
						Sorry if it was a bit of a noob question, I just hadn't seen an ODS schematic with a loop on it before.
Re: Loop questions
Not trying to be funny here but you answered your question. "after the preamp and right before the PI" which is typical to most amps. This would be where the dumblator would be patched in. Overall, the end results would be the same circuit just a matter of built in or external.dave g wrote:Ah, makes sense.
Where exactly in the ODS circuit is the passive loop typically located? I'd like to build an amp with an active loop after the preamp and right before the PI
- 
				tele_player
 - Posts: 311
 - Joined: Sat Sep 29, 2007 3:27 am
 
Re: Loop questions
The passive loop is on most (maybe all?) of the D-clone schematics I've seen, between the master volume and the phase inverter. The dumbleator, or variations, patch in here to provide a buffered loop for effects. The passive loop is the 'preamp out' and 'power amp in' jacks.dave g wrote:Thanks![]()
Sorry if it was a bit of a noob question, I just hadn't seen an ODS schematic with a loop on it before.
I don't know why Structo responded 'no' to this, it's exactly correct, and the FX get plugged into the Dumbleator's active loop.dave g wrote: When you use a Dlator with an ODS, you typically plug the "Preamp Out" into the input of the Dlator, then the output of the Dlator into the "Poweramp In"?
Re: Loop questions
Cause I misread what he wrote......tele_player wrote:I don't know why Structo responded 'no' to this, it's exactly correct, and the FX get plugged into the Dumbleator's active loop.dave g wrote: When you use a Dlator with an ODS, you typically plug the "Preamp Out" into the input of the Dlator, then the output of the Dlator into the "Poweramp In"?
Tom
Don't let that smoke out!
						Don't let that smoke out!
Re: Loop questions
Ah, yes, I had misread the whole 'Preamp In, Poweramp Out' thing which had me a little confusedtele_player wrote:The passive loop is on most (maybe all?) of the D-clone schematics I've seen, between the master volume and the phase inverter. The dumbleator, or variations, patch in here to provide a buffered loop for effects. The passive loop is the 'preamp out' and 'power amp in' jacks.dave g wrote:Thanks![]()
Sorry if it was a bit of a noob question, I just hadn't seen an ODS schematic with a loop on it before.
I don't know why Structo responded 'no' to this, it's exactly correct, and the FX get plugged into the Dumbleator's active loop.dave g wrote: When you use a Dlator with an ODS, you typically plug the "Preamp Out" into the input of the Dlator, then the output of the Dlator into the "Poweramp In"?