Ampeg V4B with TL606 and 210av help?

[Seagrass]

I just did it by ear. So I extended the shelf and opened the middle hole. Previously, with a regular shelf leight I keep the middle hole closed to make low frequency responce little bit higher. But it was not enough.

When compare the changes in this cab and this speaker, the sound is much tighter and more defined at low end and there's a nice feeling of bass on a physical level when the accents play same game with a groove.

 

[JimmyM]

I just did it by ear. So I extended the shelf and opened the middle hole. Previously, with a regular shelf leight I keep the middle hole closed to make low frequency responce little bit higher. But it was not enough.

When compare the changes in this cab and this speaker, the sound is much tighter and more defined at low end and there's a nice feeling of bass on a physical level when the accents play same game with a groove.

That’s how Jess Oliver designed the Oliver 115 for his Powerflex, which is the basis for the TL606.

 

[Redbrangus]

That’s how Jess Oliver designed the Oliver 115 for his Powerflex, which is the basis for the TL606.

Jess kinda HAD to do it by ear, but EV had the benefit of having and understanding the significance of Thiele/Small. It's news to me that EV's TL-series was inspired by the Powerflex cab, but I'll defer to your deep knowledge base of all things Ampeg and Oliver-ish.

For the OP, I'll respectfully suggest that you've lowered the box resonance point (Fb) to well below the 40 Hz you had previously, which is what JBL had recommended for the D140. The net result of that is probably going to be reduced efficiency and reduced power-handling, so approach with caution.

BTW, JBL didn't have the benefit of Thiele/Small either -- not until the very end of the D-series era, but AFAIK, they didn't change any of their enclosure recommendations, even through the K- and E-series.

 

[Wasnex]

For the OP, I'll respectfully suggest that you've lowered the box resonance point (Fb) to well below the 40 Hz you had previously, which is what JBL had recommended for the D140. The net result of that is probably going to be reduced efficiency and reduced power-handling, so approach with caution.

Probably a good time to do the rice test.

The rice test involves sweeping the frequency to find Fb. Cone excursion will dip at Fb. A little bit of rice can be used help see where the dip occurs.

Plenty of online tone generators, so you can feed your amp a tone with a phone or computer.

This one has an interface that should facilitate the rice test: Online Tone Generator - generate pure tones of any frequency (szynalski.com)

 

[JimmyM]

Jess kinda HAD to do it by ear, but EV had the benefit of having and understanding the significance of Thiele/Small. It's news to me that EV's TL-series was inspired by the Powerflex cab, but I'll defer to your deep knowledge base of all things Ampeg and Oliver-ish.

For the OP, I'll respectfully suggest that you've lowered the box resonance point (Fb) to well below the 40 Hz you had previously, which is what JBL had recommended for the D140. The net result of that is probably going to be reduced efficiency and reduced power-handling, so approach with caution.

BTW, JBL didn't have the benefit of Thiele/Small either -- not until the very end of the D-series era, but AFAIK, they didn't change any of their enclosure recommendations, even through the K- and E-series.

Ya, Jess said Ampeg copied the cab design for later B15’s as well, and the EV design is very similar to both.

 

[Seagrass]

So, today I was surprisingly happy with that changes of my 115 cab.

The dirt is easier to get from the pedal in a small space. Love this V4b. Such a beautiful amp!

 

[Drredplate]

Maybe I missed the desire for “drive” - I should read more closely maybe. A V4B run hard enough to break up will easily get you evicted from an apartment in no time, even with small speakers. It’s very loud. I’ve never used a soak, though I’m sure it would work as @Wasnex has described. I wonder about a speaker-level DI? Could it handle high amp output levels and transform it down to mic or instrument levels for recording?

Plenty passive di boxes about which will handle amp output levels. I use a cheap Behringer passive di which handles an all valve Hiwatt 100 at full stonk

 

[Drredplate]

I would use an attenuator. I have a THD hot plate which has a line out built in. There’s probably better attenuators out there now as I bought it many years ago

 

[Seagrass]

I want to add a master volume (pre amp out jack with an 10 k pot) Does anyone use it?

 

[yonkrz]

27454498[/URL], member: 350937"]My cab's internal dimensions are W18" x L22" x D13"

What do you mean by 2-1/2" deep? port depth?
I cut off a piece of plywood leaving three fingers wide at the back like the old Portaflex.

Maybe it is a not be acting scientifically, but my ears like it.

Yes sorry 2-1/2” in depth, I’ve done the same thing you did with some 606 copies just to see the outcome. And like you I only used my ears, I do however only sit at home anymore and play.I realize that the technique in tuning a cabinet is supposed to determine optimal outcome, but to me in the end if it sounds good to me/you then it worked and that’s what’s important to me I guess, but I’m no expert just old.

 

[Drredplate]

I want to add a master volume (pre amp out jack with an 10 k pot) Does anyone use it?

Most master volumes are post phase inverter. If you do that you will be pre phase inverter and may not get the distortion you want also preamp distortion doesn’t give you the output valve transformer distortion considered desirable. IMO preamp distortion is a bit “wasp in a jam jar” to my ear. Attenuator is the way to go no soldering iron required!

 

[Wasnex]

Most master volumes are post phase inverter. If you do that you will be pre phase inverter and may not get the distortion you want also preamp distortion doesn’t give you the output valve transformer distortion considered desirable. IMO preamp distortion is a bit “wasp in a jam jar” to my ear. Attenuator is the way to go no soldering iron required!

Most Masters are before the phase inverter (PI). I own a bunch of tube amps, and AFAIK none of them have post PI Master. Some people do mod amps to move the Master after the PI. This configuration is more complicated because the post PI Master has to control two signals, rather than just one.

The quality of preamp drive varies quite a bit across different models of amps. Some are bright and buzzy and some are darker/more mellow.

Some of the differences between preamp and output drive is because preamp circuits are single ended VS push/pull for most bass amp output sections. My understanding is push/pull creates a different overtone profile. This relates to whether you get more even-order or odd-order harmonics. But some people prefer odd-order and others prefer even-order. Consider that some low-powered guitar amps have single ended output sections, and some people love the distortion these amps produce.

I think a more significant difference is pushing the output section into drive taxes the power supply more heavily, so you get additional sag and compression. So output drive tends to create a different feel than preamp drive.

 

[Seagrass]

Thanks!

 

[Drredplate]

Most Masters are before the phase inverter (PI). I own a bunch of tube amps, and AFAIK none of them have post PI Master. Some people do mod amps to move the Master after the PI. This configuration is more complicated because the post PI Master has to control two signals, rather than just one.

The quality of preamp drive varies quite a bit across different models of amps. Some are bright and buzzy and some are darker/more mellow.

Some of the differences between preamp and output drive is because preamp circuits are single ended VS push/pull for most bass amp output sections. My understanding is push/pull creates a different overtone profile. This relates to whether you get more even-order or odd-order harmonics. But some people prefer odd-order and others prefer even-order. Consider that some low-powered guitar amps have single ended output sections, and some people love the distortion these amps produce.

I think a more significant difference is pushing the output section into drive taxes the power supply more heavily, so you get additional sag and compression. So output drive tends to create a different feel than preamp drive.

I stand corrected on “ most master volumes are post phase inverter “ both types exist.

 

[Seagrass]

These attenuators cost more than the amplifier itself.
It would be funny if it weren't so sad...
Or buy a fridge and blow this corrupt world to hell!

 

[Drredplate]

These attenuators cost more than the amplifier itself.
It would be funny if it weren't so sad...
Or buy a fridge and blow this corrupt world to hell!

I am with you on the corrupt world except I would use a ported 4x15!
What attenuators are you looking at! There are ones about at £130. I couldn’t say if they are any good or not but if you want the sound of a v4b pushed to the edge that’s the way

 

[Seagrass]

Who knows. I'm entering another territory.
My intuition tells me that for me all these reactive super duper mega smart attenuators in 90% of cases I do not need at all. I myself used to work in the marketing department and I know how new technologies push. It's not even that.

I like V4 clean on the verge of breaking, at the moment when the tubes and iron come into force. It's just that sound with a little "hair" at the point when you realize that the system has become one organism, but not at full volume, somewhere around 10 - 11 hours with my P.
Theoretically, I need a fixed drop to these break limits. I have no idea how to choose such a resistor for such a decrease. Maybe 2-5 or maybe 8.999 dB?
And to buy spare parts and solder them with silver solder, placing them in a box of Soviet ammunition for me is like hitting two fingers on concrete
This is only a question of correct calculations and the search for the highest-quality components.

My experience with the Tom Scholz passive guitar box (which I sold a long time ago) is that the lower I go, the worse it sounds, not only in timbre but also in dynamics. The acceptable sound was always somewhere in the beginning, with one or two clicks of the knob.

If someone asked this question, I would be grateful for the tips

 

[Wasnex]

My experience with the Tom Scholz passive guitar box (which I sold a long time ago) is that the lower I go, the worse it sounds, not only in timbre but also in dynamics. The acceptable sound was always somewhere in the beginning, with one or two clicks of the knob.

I have a fairly recent high-end attenuator and my experience matches yours. Somewhere between about 4-6dB of attenuation it starts degrading perceived tone and responsiveness.

I do believe that to some degree we are more sensitive to this degradation while playing than while solely listening. So an attenuator is still useful if the intent is recording.

I could also see it being useful for live performance if you just need to take the edge off a bit. For example if you are cranking a guitar amp to about 100W and attenuate the signal by 4dB, the power going to the speaker is reduced to about 40W. If you attenuate the signal by 5dB, the power going to the speaker is closer to 32W, and if you attenuate by 6dB, the power going to the speaker is down to about 25W.

 

[Drredplate]

I have a fairly recent high-end attenuator and my experience matches yours. Somewhere between about 4-6dB of attenuation it starts degrading perceived tone and responsiveness.

I do believe that to some degree we are more sensitive to this degradation while playing than while solely listening. So an attenuator is still useful if the intent is recording.

I could also see it being useful for live performance if you just need to take the edge off a bit. For example if you are cranking a guitar amp to about 100W and attenuate the signal by 4dB, the power going to the speaker is reduced to about 40W. If you attenuate the signal by 5dB, the power going to the speaker is closer to 32W, and if you attenuate by 6dB, the power going to the speaker is down to about 25W.

I have found that 6db is about as much as you want to attenuate with the THD hot plate.
No attenuator will be perfect. The output transformer will not be seeing the same load as a speaker and the speaker won’t be interacting with the output stage as it normally does.
I have in the past used an attenuator in conjunction with an isolation cabinet to achieve the desired sound.
It’s a compromise attenuate or be very loud.

 

[TomB]

Am I wrong using the word “soak” vs attenuator - cause that’s what we always called ‘em - or is that something different?